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Jon A

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Jon A last won the day on December 2 2016

Jon A had the most liked content!

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About Jon A

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    Senior Enthusiast

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    Everett, WA
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    2014 Denali 6.2 CC Standard Bed

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  1. Yes. There are literally thousands of SAE papers studying the oiling system and various wear rates, the effects of differing viscosities, temperatures, oil types (synthetic vs. non), etc. It's based upon these from which generic charts such as this come: These are concepts well known to the industry, not crazy ideas some millennial made up and put on the internet. OEM's typically put warnings (or in the case of boosted engines, will cut boost) when the oil exceeds 260 degrees or so to save the engine--same goes for the transmission. Quite a few people with these trucks have run into the oil or transmission oil warning lights when towing. My data in this thread shows even towing well below max on a pretty moderate pass is enough to get those fluids well above what is good for the engine or transmission. Just because you don't get a warning light telling you to pull over doesn't mean you're not accelerating wear in a significant way. Especially when using extremely thin oils in light duty (must meet CAFE standards) trucks. Here's a good overview on that subject: https://www.machinerylubrication.com/Read/518/motor-oils Here's a snippet: And how may of those were 1/2 ton trucks? If any, please provide details. If they were all HD's, that's really apples and oranges. They are designed from the ground up for such use and included dramatically larger cooling systems (when fan power is taken into account) with lots of extra coolers. They also don't come with 0W20 oil in the pan. It may have been helpful to read the thread before bashing it. In this thread I only tested a $20 aftermarket engine thermostat and tuning software for the fans (but has many other uses). About the cost of one single aftermarket wheel. Less than 1/2 the cost of many catback exhaust systems people here like (including your Borla catback) even if you throw in a new transmission thermostat on top. But people really NEED those things, right? Again, reading the thread would be helpful. It was specifically aimed at those to do tow a fair amount with their trucks. It's right in the title.
  2. That would be nice, but it's just not practical if you work an engine hard for extended periods of time. To do that on one of these trucks you'd need a massive aftermarket air/oil cooler in front of the radiator, which would destroy your A/C performance and significantly reduce your radiator's efficiency. Just not worth it IMHO for the tradeoffs alone, not to mention the cost and PITA factor. I'm not really interested in trying to run the oil 10K+ when I do a lot of towing, I mainly just want to give the engine better protection when it's working hard than the 0W20 will. I've already dropped the temps a pretty large amount; that combined with an oil that does better at those temps should amount to a big improvement over stock. Thanks.
  3. After more data, I think I've changed my mind on oil selection. I had stubbornly stuck with 0W20 (Redline) for this truck due to the number of cold starts (sometimes way below zero) and short trips this truck takes and figured I'd just try and keep it really cool. But after towing a couple thousand miles this summer and collecting data more than I had in the past, I found oil temps still exceeded 240 on the hardest portions (harder that the test in this thread) even with my current mods. Peak temp recorded on the last trip was 246. I'm fine with that temp using the 5W30 Redline that has been my go-to oil since Terry Dyson steered me toward it for my racecar 15 years ago. But 0W20 at that temp when the engine is working the hardest (and wearing parts at the fastest rate) just doesn't give me the warm fuzzy. I think I'll probably go with 5W30 for the next fill. But that further reinforces what a good idea these cooling mods are...anybody with a stock truck doing what I did would have oil temps approaching 270 degrees. Just not a good idea on 0W20.
  4. I didn't notice much difference. While the headers, etc, technically may have helped it's probably a small enough amount it would be difficult to detect. Accurately measuring mileage is tough. I've made identical long trips with identical setups and had mileage vary significantly, due to which way/how hard the wind is blowing, etc. I also did something that probably hurts mileage a bit--I tuned out the "EGR Effect" to try and minimize reversion and keep the valves clean as possible long-term (won't have any effect on a dyno). A good change from a performance standpoint but might hurt mileage a tad so it's all probably a wash.
  5. Airbags are fine in the snow: The parts aren't any more rust-prone than the entire rest of the truck. I have airbags and add-a-leafs. There's way more rust on the add-a-leafs than the airbag hardware.
  6. OK, I'll help you out. I have a BDS lift set at about 4.5" front, 3.5" rear with 35X11.5 Ridge Grapplers. Zero rubbing, even offroad:
  7. It seems 95% of people in the truck world, when reading tire specs, read the word "diameter" and substitute that for "height." That's not what it says, it's not what it means. The listed DIAMETER in the specs is the measurement of the DIAMETER--if you measure the tire sideways or not mounted on a vehicle. The tire HEIGHT will always be smaller unless your vehicle is weightless. As the OP points out, for gear/RPM calculations, calculating a "rolling radius" or "rolling circumference" from the Revs/mile spec is the accurate way to do it. About 90% of online gear/RPM calculators do it wrong. As to the OP's question, I think you're really worrying of minutia here. 661 vs. 655 is a tiny difference and pretty normal for brand to brand variation. You're really fine the way it sits. If you do want to swap to the 640 tires for a better look, you'll be hard pressed to notice any difference at all as it's still a pretty small difference. Get down to 630, 620, 610, etc, and it will start to become really noticeable.
  8. Yeah, I've been meaning to do a writeup on transmission temps and the data I've collected. Maybe in a week or two. Long story short: In stock form, my transmission ran between 195-205 even on flat ground, not towing anything, even in cool weather. When towing, if any hills were involved it would go to the 230 degree range...I even hit 240 something once. After a few simple mods, my trans temps run 30-40 degrees cooler on average and has yet to hit 200 degrees, even when towing at 15,000+ GCW up long 6% grades in 90 degree temps. Basically for any given situation, you can expect the transmission fluid to be 30-40 degrees cooler than it would be with the stock setup. Your factory cooler is very large, the stock setup just doesn't use it very well. Mods, in order of importance: 1) Bypass stock thermostat/install aftermarket thermostat. The stock thermostat is the main culprit. Truckguy82's was non-functional, but I don't like the design much--even when working correctly I don't believe it forces much fluid through the cooler until well over 200 degrees. This mod worked even better than I though it would. Transmission fluid heats up very slowly, so when you drop your baseline temp by 40 degrees or so, even on a very, very, long hill it just never has the time to get hot as it would stock as it takes a long, long time to make up that 40 degrees. Simply bypassing the stock one is pretty much free and will give you all the gains, but especially being in Canada adding an aftermarket thermostat is probably a good idea. I used a 140 degree just to set the floor--on long highway drives in sub-zero temps I'd be worried the trans temp may never even reach triple digits without one. 2) Program the fans to come on more aggressively. The fans help quite a bit even at highway speed, and obviously a ton at low speeds. You have a 2014 so it's probably out of warranty anyway, so that shouldn't be an issue. I show how to do it with HP Tuners in this thread: You'll want to replace your engine thermostat with a cooler one to use those settings so the fans don't run all the time--the GM 194 degree or lower. I've found the 194 to work well, and you never have to worry about it leaking in the winter as you do with the aftermarket ones that have a different gasket design. If you had monitored your coolant and oil temps along with the trans temps, they likely would have scared you. The lower temp thermostat and fan settings help a ton for max coolant and oil temps. 3) By-pass the factory in-tank cooler in the radiator. It's almost always working as a heater instead of a cooler. I found doing this helped some at highway speeds, but quite a bit at low speeds. Again that's basically free and easy to do when setting up an aftermarket thermostat. If you do those things, I guarantee you your trans temp issues will be a thing of the past. You originally asked about gears. I would not recommend doing gears specifically for the purpose of reducing transmission temps. Yes, they will help by keeping you in higher gears longer, but I think older transmissions with fewer gears that didn't keep the converter locked nearly as much probably benefited more than these transmissions do. It's just a really expensive, round-about way to reduce transmission temps. Improving the transmission cooling system directly makes much more sense if that's your goal. But gears are a great mod, especially with a 6-speed, especially for towing. They have lots of other benefits--will make the truck a lot more fun to drive, make towing more pleasant, improve grade-braking, etc. So I'm all for doing them for those reasons, just think of help with transmission temps as a side-benefit as that's a lot of money to spend if lowering trans temps is your only goal.
  9. 3.08 to 3.73

    Being worth the effort is, of course, in the eye of the beholder. But in my opinion, absolutely it will be worth it. If you can get the parts for that price, they're in good shape and install/set them up correctly it's a fantastic deal that will make the truck more enjoyable to drive, especially when towing. Even more so when you add larger tires. Most here who have a shop install gears pay $2000+ for it (even without new carriers) and typically say it was one of their favorite mods and definitely "worth it" even at that price. I would expect the mileage changes to be negligible. You'll take a hit with the larger tires with either ratio. With larger tires there are many scenarios where the 3.08 gears become more of a hindrance than a help. If you want the best mileage with larger tires, try and stick to lighter weight/lower rated (P-rated) tires.
  10. Certainly, it all depends upon the use. Under different usage (or different tests), the results of different vehicles will not be proportional to the results on the EPA tests. One vehicle can be higher than another for one type of use, but lower for other uses or tests. A good example of this is the Ford Ecoboosts...they do pretty fantastically on the EPA tests, but drive lots of hills/mountains, tow a trailer and their mileage drops like a rock (you can have "Eco" or you can have "Boost" but not both at the same time). The 5.3 and 6.2 are a lot more similar so the difference between them won't be as dramatic, but for different uses don't expect the mileage difference between the two to remain exactly proportional to the ratings. For some use, the 6.2 can actually do better than the 5.3.
  11. No. Every last detail of the tests are dictated by the EPA. How well they do or do not reflect real-world use is entirely on the EPA. https://www.fueleconomy.gov/feg/how_tested.shtml
  12. Aftermarket Brake kit

    Nice! Any chance you could measure the piston diameters before you put them on?
  13. You are confused. Calling a bunch of people who are actually running these tires liars simply because their actual 1st hand experience is different than your cousin's brother's uncle or whatever has nothing to do with democracy. It has something to do with you.
  14. How did your speed limiter get changed? Somebody had to do it, it doesn't just happen by itself.
  15. So your answer to the overwhelming majority of users reporting their first hand information is to call them liars because you WANT to believe something else? Go crawl back into your cave. BTW, I typically replace offroad tires when they get much below 50% tread. Not because they're "used up" but because offroad traction suffers enough I'd rather have a set of new tires. That's usually somewhere around the 30K mark, these should exceed that easily.

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