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Found 975 results

  1. It's never too early to start talking about the process of shopping around for a dealer, pricing, the ordering process, deposits, and production delivery times. Although we're still months away from orders being accepted, this thread is meant to be a place where everyone can check in and share their experiences as they go through the process. I'm also going to document as many important dates in this initial post as I can. I'll attempt to keep everyone up to date on start of production, any ordering limitations, and when the ordering system will go live. NEW UPDATES AS OF: April 25th, 2018 T1XX- 2019 Chevrolet Silverado and 2019 GMC Sierra - Important Ordering / Production Dates Pre-Production: NOW - Captured Test Fleet Production Confirmed as of March 31st. Fleet Order Entry Avaliable On Crew Cab: 4/26/18 Double Cab: 6/21/18 Regular Cab: TBD Retail Initial Consensus Month Crew Cab: May 1st Double Cab: August 1st Regular Cab: TBD Initial Dealer Order Submission Process (DOSP) Crew Cab: 5/17/18 Double Cab: 8/16/18 Regular Cab: TBD Production Start Up For Dealer Delivery Crew Cab: Quarter 3 - July/August/September Double Cab: Quarter 4 - October November December Regular Cab: TBD 2019 Chevrolet Silverado Start Up Schedule 2019 GMC Sierra Start Up Schedule This post will be updated whenever new information becomes available. Please contact me if you can help clarify any of these dates.
  2. John Goreham Contributing Writer, GM-Trucks.com 9-11-2019 General Motors has announced that NHTSA is mandating a safety recall for the following vehicles: 2014-2018 Chevrolet Silverado and GMC Sierra Pickups (1500 / 2500 / 3500) 2015-2018 Chevrolet Suburban, Tahoe, GMC Yukon vehicles 2015-2017 Cadillac Escalade NHTSA reports that the amount of vacuum created by the vacuum pump may decrease over time. The group says that as the vacuum level drops, the brake assist decreases, and that this increasing braking effort, extending the distance required to stop the vehicle, thereby increasing the risk of a crash. This new recall covers 3.4 million vehicles. The Problem: The brake pump uses engine oil to lubricate itself. If the pump becomes clogged with engine oil sludge the units ability to create vaccum is diminished over time. As a result, braking force and ability also drops. The issue is usually accompanied by a "Service Brake Assist" warning message in the dash. The Fix: GM will reprogram the computer that controls the secondary brake assist pump. The secondary pump will now activate at lower speeds and different situations quicker to compensate for any lost output from the main pump. Since the pumps are not failing, GM has decided not to replace them. GM's number for this recall is N192268490. In compliance with federal law, GM will notify owners, typically by snail mail. GM says that its dealers will reprogram the Electronic Brake Control Module. However, GM has not yet provided a notification schedule. Owners may contact Chevrolet customer service at 1-800-630-2438, Cadillac customer service at 1-800-458-8006 or GMC customer service at 1-800-462-8782. If you own one of these vehicles and wish to check to see if your vehicle is included (or not) you can do so at this link immediately. As with every safety recall, customers will not be charged by GM for the needed repairs or modifications. NHTSA's public information on this issue indicates that many accidents have been reported to NHTSA including some with injuries. This recall is the result of a NHTSA investigation that lasted nearly a year. In its investigation report, NHTSA noted the following details about the problem:
  3. What’s the cheapest most efficient 3/5, 4/6 lowering kit or drop for a 2014 Silverado crew cab standard bed 2wd 5.3???
  4. I have a 99 GMC Sierra 1500 4X4 and i was wondering if there is a specific brand of o2 sensor that i need to use... because someone was telling me that i have to use OEM for this truck because they dont like NON-OEM o2 sensors. and that they act up and jump all over the place. this guy wanted to charge me $89.99 a plug as well... can someone please help me out with this i would greatly appreciate it...
  5. Anyone else with a new 2014 Sierra having an issue with the frame rusting and paint/wax flaking off? I have 3000 kms and it looks horrible. I also own a 2011 Canyon service truck with 105kms and the frame looks like new. So irriating as my Sierra is a beautiful truck aside
  6. I was wondering what a good swap would be. I have the stock 5.3 but I want some umph. I travel for work and still need gas mileage but I have hit a dead end in research. Can anyone help me?
  7. I know the 6112s are semi-new to the community. My question is what would be the lowest possible notch I can install these and still have enough clearance to fit 275X 65R 20 KO2s. I’d imagine the notch settings are similar to the 5100s accept there is 1 extra notch I believe. I have been searching online for the past week and cannot find anyone that confirms the lowest possible setting to fit these tires. I know I can install them at the highest setting and fit just fine, But I am trying to keep rake in the rear due to occasional towing and i do not want to add a leveling block to the rears. I was thinking the third notch (1.25” of lift) would work but I’m not sure if It will get rubbing. Does anyone have any idea on this? I currently have a 2.5 inch leveling spacer but do not want to install it when I switch to the Bilstein 6112s. Thanks!
  8. 2017 sierra A/T crew cab I have the most annoying tick noise over bumps, coming from the b pillar behind my left ear and it is driving me brick house, I've pulled at the trim off put my hands on everything made sure everything is tight, stuff rags in between contact points, I've run out of ideas, anyone have an guidance for me, I'm a ex gm technician of 5 years , I know what I'm doing but of course my own truck baffles me..per usual any new bulletins or tsbs?
  9. Hi all, I am a relatively new member to the forums and a first time truck owner. I've had my truck for about 2 years now and finally decided it was time to upgrade my baby. After months of researching, I decided to start off with a leveling kit, wheels, tires and rode on that for about 8000 miles before I saved up enough to do a lift. As it stands, I decided to go with the 4 inch BDS lift kit with the fox shocks upgrade. I narrowed my choices to Fabtech and BDS after tons of reading on this forum and the conclusion I came to for the price points, BDS made more sense and appears to be more spot on with the suspension geometry. Given that I am no expert, I could be wrong on that, so definitely don't quote me. The shop that did my install is an authorized BDS retailer and as a result, they prefer installing BDS kits on their trucks. One thing I noticed is that most people try to jump up to the coilovers right out of the gates in the name of preserving ride quality and Im here to say that you don't need to do that. Even the guy at the shop told me that it wasn't necessary to do and it doesn't guarantee that you will enjoy that ride quality. I was in that same boat until I decided to go ahead and try out what BDS has to offer before I spend more money on the kit itself. Ride Quality My experience of driving my truck pre-level and post-level - I felt no difference in the drive itself except some amount of additional harshness going over speed bumps. At that point, I expected that amount of harshness, in fact I expected worse based on reading what people had to say about how leveling kits ride. My experience of driving my truck after going from the leveling kit to the 4" lift - the ride is absolutely beautiful. Having driven a friends Yukon Denali, I can say that the ride of the truck is slightly floaty on the road similar to how the denalis ride, yet still very connected (not sure if that makes sense to anyone else but me). I absolutely love the way the truck rides and I feel that it's on par with stock, if not a little more insulated with the added suspension travel that absorbs some of the bumps and imperfections of the road. As it stands, I have driven with the kit for about 450 miles thus far and I have zero intentions of adding the coilovers to the setup. (500 mile suspension re-torquing coming up soon) Another added point of comfort for me is if my ride quality does deteriorate for some reason and the coilovers become a necessity, getting rid of the front shocks is not like throwing away an expensive pair of shocks. I also potentially have the option of adding kings in the event I ever need to go down that route... I hope that for someone out there, this helps make a decision on the kits with the plethora of information available and I'm happy to answer questions about this lift. Daily Drivability With this being my first lifted truck and first truck to begin with, I was really concerned about how drivable the vehicle would be compared to stock. The only difference I notice regarding drivability is making a turn when the wheel is at full lock in either direction feels like there is more turning radius involved, but hasn't been an issue. The bed and the bed steps are still very reachable / usable - I'm 5'8". The sidesteps are a little bit taller to get up to than before but it's not a pain in the ass or to the point where I hate the truck or my decision - I'm going to be keeping an eye out for a good deal on articulating running boards from AMP or RBP eventually. For anyone who enjoys driving fast - I haven't felt powerloss in the vehicle, especially being that mine is a 6.2L. I did definitely notice that there are a few moments where shifts take longer, but Im sad to say I need to address an issue that involves the torque converter and creates a shudder when accelerating as though you're driving across rumble strips but that's a different topic for a different time. It drives fast, feels stable, and is fun as hell. Fuel Economy Impact I honestly haven't had any impact on my fuel consumption since I began upgrading items on the vehicle. This might change over time, but as it stands I get about 20-22 MPG highway and a range of 13-16 MPG City based on traffic levels. Other Notes - 2017 GMC Sierra SLT Premium Plus Package with Z71 Package | 6.2L V8 - Denali Cluster Retrofit - 33" Nitto Ridge Grapplers - SCA Performance 20x9 Black Widow Wheels | 0 mm offset - Blacked out emblems - Rough Country Tri Fold Bed Cover - GM Borla Exhaust with Dual Outlets (There's actually a tilt downward in the exhaust because the dealer failed to correctly install them with the appropriate hangers to the frame - going to be corrected soon) - Black Chrome Exhaust Tips - Rear Wheel Spacers soon to come (BDS lifts push the front track width out, I want to even out the stance) - AMP Research power steps soon to come - Cold Air Intake soon to come Pictures
  10. Denali Cluster Retrofit - A Review. As I'm sure many other readers of this forum have done, I found myself going through some of the posts and checking out some cool things people here have done to their trucks. I happened to stumble on the Denali Cluster retrofit and from the moment I saw it, I had not stopped thinking about doing it. Being someone who opted for a non Denali truck but still paid a pretty penny, there was always a small itch in the back of my mind at the lack of a couple features that these trucks have compared to other lower priced vehicles with less prowess - the instrument cluster being so plain is one of them. After eventually deciding to scratch that itch, I got in touch with Chris from White Auto Media (WAMS | http://www.whiteautoandmedia.com) about the Denali Cluster retrofit. Now, there are several posts with a wealth of information about this (main one attached below) and if you are interested in doing this modification, I highly recommend you start there and understand everything there is about selecting the right cluster for your vehicles model year. After exchanging a few emails with Chris, he noted that I was able to have him source the cluster for me and take care of the programming. At the time, I was unable to locate the correct fitment of cluster for my vehicle and the sellers on eBay just seemed to be too sketchy, some had cracked plastic lens covers, and others just didn't provide enough information for the amount of money they were asking for. As a result, I went ahead and submitted my details to Chris via his website and ordered the cluster. It did take two weeks plus a handful of days for sourcing the cluster, programming it, and shipping it to my doorstep. Not only did Chris make it incredibly easy to do this modification, his kindness in sharing information about the entire process to ensure that I had the right fitment, right cluster, right programming, made this experience all the better. Once I got my hands on it, I was able to get it installed in my vehicle in about 10 minutes given the right driver to take out some 7mm bolts and a little bit of prying with my fingers. In the end, I have a fully functioning, slick looking, Denali Cluster. Install video: Phil Gamboa did a fantastic job documenting the install and how easy it was. My only deviation from the video instructions was not taking off the bottom panel where the hood release latch is located and I was safely able to install the cluster without breaking or scratching any components in the process. Link: https://www.youtube.com/watch?v=HLq-VVcEL8I I attached a photo of my working dash to the post! I'm glad to have went this route and hopefully, I will find a way to give Chris my business again in the future! @GTPprix IMG_2532.HEIC
  11. **SOLD** 2016-2018 GMC Sierra Elevation grille that's been professionally painted black. This is a brand new OEM grille. I ordered it and decided to go with a different style grille, absolutely nothing wrong with this grille. Shipping to continental US is free, local pick-up near St Louis MO. Price is $500.
  12. Hi. I'm trying to replace the belt and having trouble finding the notch on the tensioner to attach a break out wrench or some other tool to release tension. The vehicle is a 1996 GMC Suburban K2500 7.4 liter Vortex engine with AC and approximately 140K miles. These are the best pictures I could manage given the tight clearance. Here, the tensioner can be seen below the alternator. Here are similar parts I found online, but not sure if they're the same exact part. If anyone has worked on one of these, I'd appreciate some suggestions.
  13. I just purchased a new GMC 2500HD at Allen GMC in Orange County Ca. A week after delivery I discovered the entire underbody of the truck was covered with dried Road Salt. I did not inspect the underbody prior to purchase because I didn't think I had to. To make things worse GM is well aware of the issue. In April 2018 GM issued Bulletin PI0281G (attached) to Dealers. So GMC builds this beautiful truck, then they take it out in to a storm on roads covered with a corrosive chemical (road salt). They don't bother to wash it off they just ship it out to a Dealer. In my case California. You should know as the temperature increases so does the rate of corrosion. Having grown up in the "salt belt" Wisconsin I know the extreme damage done to vehicles by Road Salt. So GMC in an effort to cover their tracks notifies Dealers of the issue and instead of a discount or compensating customers they just say "that's the way it is. No consideration for damage will be made other than normal warranty coverage" . To me there is something very wrong with being aware of major corrosion damage to a vehicle and not disclosing that fact to the buyer! It would be different if they delivered a new vehicle to me and I covered it in salt, but, I didn't get the chance to even get it over the curb the damage was done pre-delivery. I pursued a vehicle replacement through the dealer and GM Customer Assistance but GM is refusing to replace the vehicle. Buyer Beware! Inspect the underbody of your vehicle before purchasing! I will post an update when I have it but the bottom line is I'm not getting stuck with this corroded junker. I bought a new truck and I expect to get one. PI0281G Underbody Corrosion.pdf
  14. I normally get vehicles without sunroofs, because the headliner height is lower on vehicles with sunroofs and the headliner presses the left side of my head to the right in the driver seat (confirmed this in a 2019 3500HD on the dealers lot last month). I'm 6'3" and it's mostly in my torso. Does anyone know if the height of the headliner in the front cabin becomes equal with the rear headliner height if the sunroof is not optioned in (in other words without the sunroof is the headliner is closer to the actual roof panel since it's not hiding the sunroof mechanical under it)? I'm hoping to order my 2020 GMC 3500HD Denali SRW soon and this is the one option I'm not sure about yet. I don't care about resell or trade in values because I'm keeping this truck for at least the next 20 years, but if there is no height difference I might as well get the sunroof and pre-pay for my chiropractor.
  15. Hi All, new to the forums, I just bought a 2016 GMC Sierra 2500 HD Denali and I’m having a hard time with the 110v power outlet. Ever since I bought the truck it hasn’t worked. I removed the passenger side panel and checked fuse #35 and noticed it was blown. With the truck off and nothing plugged into the outlet I removed the fuse and the second the new 25amp made contact the fuse blew instantly, I tried it again with another 25 amp fuse and same problem. Took to the dealer and they’re wanting to charge me $600 to diagnose the problem as they have to “rip apart my whole dash” to isolate the issue. I looked inside the outlet and nothing is inside that would short it out. Before buying a plug or an inverter I wanted to ask here if there’s anything else I should try? TIA
  16. Good evening everyone! This is my first posting on the forum! I’ve got a 2011 GMC 2500HD 6.0 that has visited 2 tuners in the central Texas area. I have a TSP VVT2 cam, 3600 converter, forged internals, And exhaust, with more to come soon. I have been told by these shops that my truck could not be dialed in like it needs to be due to missing airflow tables on HPtuners. Supposedly the 2011 HD’s have a odd computer that has to be torque based tuned. I am having idle problems... pulling up to stop lights and turns the truck will die 8/10 times, but starts right back up. Anyone know a way around this hiccup? These shops have gotten it to the best they could, which still is not enough obviously.
  17. I am currently looking for a mechanic/shop that will fully delete a 2017 Chevrolet 2500HD (L5P), hopefully around the Mississippi/ Louisiana area. Any help will be greatly appreciated.
  18. Hello, this will probably be a very strange post, but I really don't know where else to go for help. My older brother has gone missing in Northern California. This is not a joke in any way. Here is a link to the law enforcement posting on Facebook. His 2015 GMC Sierra was found on the side of the road a few dozen miles from his home. His truck has an Intellilink interface in it (I believe that's what it is, the big fancy touch screen that comes stock). He never paid for GPS services, but I am wondering if there is any way to pull off a history of where the truck has been driven. The cops won't do it because there is no evidence of a crime being committed so they don't have the legal backing to do such a thing (if that makes sense). Regardless, my brother has been missing for 5 days now and my family is really trying to find out what happened to my brother. We have his truck in our possession. Would anyone be able to help me pull off the navigation history? This might be a huge help in letting us see what happened the hours before he disappeared. Thank you for any help. I apologize if I'm violating forum rules of any kind.
  19. Thom Cannell Contributor, GM-Trucks.com March 7th, 2019 Heavy Duty trucks mirror the contest for market domination in light duty trucks. This year both GM and Ford announced significant upgrades to the engines powering their all new 2500 and 3500 HD trucks as each company upgraded their diesel engine, and delivered new gas engines. At GM, the launch event centered on Chevrolet, who brought in truck writers from every segment—popular to fleet management—to Flint, Michigan’s Flint Truck Plant. Flint is the original home of General Motors trucks and the spiritual and historical home of the UAW. So, Flint Truck Plant is receiving an all-new facility constructed and designed for just HD trucks, with the former truck assembly areas destined for warehousing and future projects. New L8T 6.6-Liter Gas Engine We first spoke to Mike Kociba, a GM engineer and part of the Small Block team to learn about the new 6.6-liter V-8 engine we'd been anticipating. Mike told us the new motor “is a marriage of the six-liter it replaces and an upgrade in technology levels to Gen 5 architecture.” A careful look will disclose similarities in key areas where GM has maximized their experience with the six-liter’s durability and improvements in performance levels derived from Gen 5 architecture. “Specifically, new here is the gray cast-iron block which is unique for this application, hyper-eutectic purpose-built pistons for this application and heavy-duty requirements, forged powdered-metal connecting rods, and a forged steel crankshaft,” Mike continued. The most significant change is the addition of Direct Injection. It’s all new, an industry first for the heavy-duty market and new to GM trucks. “When we added DI, we took the roughly 400 KPa fuel pressure from the low-pressure pump and dialed it up to roughly about 15 mPa for engine operation under key conditions,” Mike continued. “That allows us to increase compression ratio, now 10.8:1 using regular fuel. Without DI you're not going to hit those numbers without losing a lot of spark efficiency. With those additions, and the six millimeter longer stroke, that gets us up to 6.6-liters.” “That suite of changes allows us to hit class-leading gasoline engine torque, at 464 foot-pounds at a lower engine speed than the outgoing six-liter was optimized for. I'm proud of its 401 horsepower, which is SAE Certified, no games, legitimate. This (engine) is purpose-built to crank out those numbers day, after day, after day with no compromise in durability. Customers can have confidence they're going to pull, tow whatever trailer you need.” There are other new features like an all-new water pump and a massive cooling fan to meet the demands of the HD customer base. New is how the water pump drives the fan through a one-inch shaft using purpose-built bearings to handle loads. Another first for HD is a variable-output oil pump. “No mater what the severe operating condition is for the customer, the pump is capable of dialing in more, or less oil pressure regardless the requirement. The engine features an aluminum oil pan, nylon 6-6 air intake, and stainless steel exhaust manifolds unique for the Heavy Duty market. That’s because HD market has specific requirements for (fuel) enrichment and these stainless manifolds will meet those requirements. “We have variable dual-equal valve actuation, like on light duty, where intake and exhaust are phased together and controlled through the actuator on the front cover. It's chain driven for accessories.” GM designed this engine specifically for upcoming standards for particulates and NOx emissions standards. “With this architecture we're not just making power and torque, but improved emissions and improved efficiency.” Mike continued. We noted the massive valves, which Mike said are common with Gen 5 architecture for valve layout and their pushrod technology. “That's how we get this compact shape. When you compare the size of the two engines, they're similar, which is due to the common 4.4-inch bore spacing.” A unique feature of the new engine is inter-bore cooling. Coolant flows between the Siamesed bores, notably in the upper bores where there’s a tendency to generate higher temperatures. “For two-valve technology of course you've got the spark plug, and the fuel injector, splayed outside. To avoid heat, we have the coil mounted directly on the rocker cover and the boot mounted next to the manifold with industry-standard individual coils for each cylinder.” This is great stuff, we though, but engine development isn’t cheap. So, why a new 6.6-liter when the 6-liter was doing well? “We needed to improve to Gen 5 level of technology to be sure (the engine) is capable of delivering on durability requirements. Customers love the convenience of gas, but if you look at the market—for instance trailers with more gadgets and slide-outs—everything is getting heavier. Customers want to be sure they can tow with confidence, no compromises, whether it's fuel economy, power, torque, emissions, efficiency, they don't want to pull up to their neighbor and have to make excuses. That's what we targeted. No compromises. With the significant technology we put into this engine, it makes segment-leading torque without compromising efficiency or emissions. Peak torque is at 4,000 rpm, 400 rpm lower than the 6.0-liter. Three things enable the new 6.6-liter's better power output. Direct injection (DI) allows us a higher compression ratio; longer stroke is good for increased torque (but not as good for horsepower as piston speeds are high) and for heavy-duty application where you need torque everywhere it’s why we focused on a longer stroke to get to 6.6-liter displacement. Those changes enabled us to broaden the torque curve, which is up 20% everywhere, for greater work potential.” We thanked Mike and asked if we’d missed anything. “Small engines with turbochargers allow them peak torque off idle, but for heavy duty we don't want that complexity. For the Heavy Duty segment we (General Motors) have durability requirements—Global Engine Durability—that are unique and very long and stringent requirements. We know customers need 401 horsepower and 464 lb.-ft. of torque today, tomorrow, and every day for years to come with no compromise in durability. We know our customers and, if they can't use their truck today, they might not get paid. That's why we focus on durability.” Brand New HD 6-Speed Transmission With that in mind, we next spoke to the systems chief engineer for six-speed FWD and RWD transmissions Rich Mardeusz. More power and more torque tend to break an older transmission. So, we wanted to know what changes had been made to the new transmission to carry the additional torque. “We started with the 6L90 that's in the current HD vehicles and full-sized vans (and ZL-1 Camaro and CTS-V), received the horsepower and torque curves from the engine engineering teams and then performed an analysis of all mechanical components from front to back,” Rich said. General Motors uses specific simulation tools for different parts. “For instance, we have a "gear damage analysis tool" for analyzing the gear set and how much damage it may receive over the life of the vehicle,” Rich told us. The result was a need to improve the torque converter and the clutch pack, which needed to be more robust to accommodate the greater power output of the upgraded 6.6-liter V-8 engine. From a clutch pack standpoint, changes were simple, according to the engineer, as there was enough room in the case to add a clutch and one backing plate to each of the clutch packs to handle additional power. When it came to the torque converter, things changed. “We looked at the components from a heavy-duty diesel torque converter and a high-output gas torque converter and then took the torque-carrying components from the diesel and married them to the spring and damping components from the gasoline torque converter. That’s what was needed to accommodate the approximate 22 percent across-the-board torque increase.” So, the new torque converter can A) handle the added torque of the new engine and B) damp out the firing frequencies from the gasoline engine, which are significantly different from a diesel engine. All of the shafting and gears were able to handle the torque. Interestingly, there is no dipstick. GM has the confidence to eliminate it, and only change fluid at suggest intervals of approximately 100,000 miles, more often for those who mostly tow, or drive over mountains with full loads. Another surprise, the transmission uses GM-spec Dexron VI fluid, GMs standard since 2005, as they found no reason to change. 2019 L5P Duramax 6.6-Liter Once we’d completed our gas powertrain interviews, we turned to the diesel side of Heavy Duty. We spoke to Max Sala, whose Italian accent tipped us to an affiliation with GM’s diesel engine center of excellence in Turin, Italy. Max said that their objective for the new Silverado HD was to increase towing capacity and ensure functionality with the new Allison/GM transmission. Remember, the Duramax 6.6L Turbo-Diesel V-8 engine makes 445 hp. and 910 lb-ft of torque. “We added a bigger fan now 28-inches, a bigger oil cooler that is upgraded from 14 plates to 19 plates, and we fine-tuned the cylinder head gasket” Next up were improvements to the engine-brake capacity, taking into consideration towing capacity. “It’s better by 14-percent and we introduced smart activation of the engine brake,” Max continued, “There's still a button for manual activation, but for safety there's automatic activation at certain RPMs.” Under the new control system, the powertrain will recognize any need for the engine brake and activate automatically. For instance in driving down hill and forgetting to shift, the higher RPM means automatic activation. “With that, we have better after-run strategy. Every time you tow uphill, temps rise and you have a message to cool the engine when stopping. If, by chance you forget and close the door, the system cooling system activates automatically for up to 15 minutes to cool the engine for reliability.” That isn’t the end of changes, as the engine has been completely recalibrated to match the new 10-speed Allison transmission. “Emissions have been improved and fine-tuned to maintain the best efficiency the transmission can offer to our customers.” With these changes, most importantly, Chevrolet says they are now capable of delivering full torque at any time, in any gear, and that they have done everything to the engine, transmission, driveline, drive shaft and frame to improve strength and durability. “What's important is how safe (the new HD trucks) will be and how comfortable it will be for our customers to drive these huge trailers up, and down hills.” Max concluded. Allison transmissions have gained a peerless reputation for strength and durability. Adding a 10-speed transmission branded with the Allison name is a great choice. David Ames, now GM assistant chief engineer on the Allison transmission and liaison with Allison, is a former Allison engineer. A natural fit. The 10-speed is a collaborative effort with joint development of the analysis, engineering, as well as testing. So, testing was performed at Allison and at GM, each with their own set of rules and test regimes. “We go back and forth”, David told us. “Today we have a ratio-span of five and this transmission has a span of 7.2, so the new 10-speed provides both more overdrive and a lower first gear.” We asked about the projects’ starting point. “We (at GM) come out with a "here's what we're looking for" and we begin an internal development contract. It was a pretty clean sheet of paper. So, the controls on the bottom are from a smaller 10-speed, some pieces and parts, but not the entire controls package. For the most part, it's all new to handle the increased power and much larger torque. We collaborated with Allison on this transmission (GM does have a 10-speed transmission of its own) which made it necessary to meet their (Allison) design requirements, their analysis requirements, their engineering requirements, as well as our own. It's a very compact transmission. If you had a 6-speed for comparison, this more dense, more compact and solid to get ten speeds into a package that would still fit nicely into the vehicle and not take up too much space,” David continued. This transmission’s torque converter has a lock-up clutch and is unique in that it will lock up in first gear, even under max loads. So, if you're pulling 33,500 pounds, you can do a first gear launch and lock up right away, which helps get rid of heat. We asked David why this is important. “Normally in first gear you're under high torque and generating a lot of heat, which puts a lot of demand on the cooling system. Locking up gets rid of that heat and the 7.2 ratio gives you a lower first gear. For instance, the six-speed uses a 3.1 first gear and the new transmission has a much lower 4.5 first gear. It's got four planetary gear sets, six clutches and the main place you'll notice the ten speeds, not only in launches and driving with heavier loads—it's very smooth—is going down a grade. Often you're trying to downshift to save brakes and having ten gears you can usually hold the right speed and not feel like you're running over the car in front of you, tapping the brakes or going too slow.” “Also, we built in the first OEM PTO option. Note that the chain drive to the PTO is engine-speed driven rather than turbine-speed driven, which is important to many commercial customers, and it’s quieter drive than gear driven systems.” We asked David for an overview of the combined Duramax-Allison package. “For those who need it, it’s a nice package, one we're very proud of because of the outstanding durability. I think we're going to do a better job of putting power to the road than anybody out there. Whatever torque the engine is putting out, it's getting to the road in an accurate way. I think this transmission will be far more durable than people need it to be. Four-five years from now people will understand how durable it is.”
  20. Anyone else with a crew cab (or possibly other cab style) notice that while driving at speeds 55mph or higher with the rear door windows all the way down results in an almost deafening whop whop whop like or flapping type of sound that practically hurts your ears? Would be what I would call a low frequency. It gets worse the more open the windows are. My 2016 Sierra Crew did this as well, can't recall if my 2012 LTZ Crew did it or not but I think it did. Any ideas what is the culprit? I rarely drive with the rear windows down but when they are, it's maddening and almost makes my ear drums feel like they're going to pop. Not something I'm worried about more than curious what causes it. Thanks in advance!
  21. The LED lights in the passenger side headlight of my 2016 Sierra 1500 Crew Cab are sporadically not working. Sometimes the are on, sometimes they aren't. The driver side functions properly all the time. The main light in the center of the headlight works fine all the time. I took it to the dealership and they replaced the whole headlight. When I turned on the truck a few hours after I picked it up from the dealership the LED lights were not working again. Has anyone had or heard about this issue? I'm going to take it back to the dealership, but would love some advice from anyone else that has dealt with this issue. Thanks!
  22. Will a factory touch screen from a 2007-2013 suburban, Silverado, gmc fit right in my 2008 gmc 2500 ?
  23. I have a gmc 2013 Sierra slt 6.2l. I have been lookn to swap the factory grille to a 2013 Denali style grille. One supplier was telln me that it will not fit. I cant not find anything that it wouldnt fit. Has anyone done this swap? Can it be done? Thanks in advance for any info.
  24. Hello all, I am a new GM owner that has converted over from Ford. This will be a slow build but plan to have many updates. I am also brand new to aftermarket parts, as I have always left everything stock. I am going to do my best on trying to figure out this site so bare with me a bit. The first picture is of the first week I owned the vehicle, second is when I discovered Plasti-Dip, and third is the latest after I did a few installs. My next purchase will more than likely be either Bilstein or rancho shocks. I want bigger tires, but the tires on it now are brand new so it is hard for me to buy new right now. I was really close to Plasti-dipping my wheels because I have been wanting black wheels, but I think I am going to hold off. Any suggestions? So far my upgrades are: Tow Mirrors Leveling kit Plasti-Dip Emblems Magnum RT Steps Tonneau Cover
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