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To preface this thread; I am not looking to go to Bonneville or the Autobahn. Now that that's out of the way... 98-99 MPH when it's still pulling hard, and is on T Speed Rated tires, is a bit of a let down. I don't go that fast all the time, but I have found myself hitting the nanny state leash a time or two on the toll roads not far from where I am. In the immediate future is a CAI cold air that I will need a DiabLew Tune update to get the best results from. My thinking is that when he does the update, he also moves the limiter. Here is my question: What is the max safe top speed we can set it to? I say max safe from the stand point of not exceeding the drive shaft's max rotational speed, what Complete Street Performance called "Critical Speed". The truck in question is a 2018 Silverado 1500 LT TX Edition, Crew Cab, Short Box, 2WD, 5.3L, 6L80, 3.42 G80 rear diff, one piece driveshaft, on a 265/65R-18 112T Tire. If going off the speed rating of the tires, one would say 118. The speed rating chart is common knowledge, but not the end all answer. Again, what I'm not sure about is the max speed of the truck vs rotation speed of the drive shaft with my combination of trans, rear diff, and tire size. I'm thinking... 110-115. Thank y'all in advance!
By Bill Reinhardt
Make/Model: GMC Sierra Year: 2014 Engine: 5.3L L83 Trim: Work truck (blue blood truck right here) Transmission: 6-speed w/ 4 wheel drive Gears: 3.42 Miles on truck: ~53k Miles driven on tune: ~3k Performance Mods: None, apart from the tune of course Other mods: bed cover, remote start, tailgate damper Tuner: Diablo Intune I2 Truck role: Getting to/from work and doing work. Have another car for long trips
I purchased a Diablosport Intune I2 for my previous vehicle, 08 Colorado I5. The tuner for that truck was the best investment I ever made, especially for the transmission tune. Lightning-quick shifts, more power, better throttle response, no complaints. That truck has since left my life, needed something with more payload, in comes the Sierra...
The truck commutes 15 miles per day for work and is otherwise a weekend warrior. About 80% city, 20% highway driving. Had no complaints with how the truck drove, until I started noticing an occasional downshift "clunk" when going around corners between 20-30 mph. Then, I remembered how awesome the I2 made my Colorado transmission. Said, "Screw it, lets tune this thing and see if the problem goes away." So I purchase the extra license for my i2, install the canned 87 octane/firm shift tunes, and go out for a drive... Big mistake. The canned transmission tune was QUITE bad. Started investigating, lots of complaints on the Diablosport forums, only solution is to try a Diablew tune. So, $150 and 3k miles later, here we are!
Contact Diablew with your information, wait 5 seconds for him to respond, pay the man, follow the instructions, profit (for him... and you, eventually). Don't want to cover this too much as it's not that interesting. Onto the tune!
One engine and one transmission tune provided with tweaks available upon request. The engine tune can be provided for the octane of your choice, but keep in mind that the 87 and 89 octane tunes are the same with no spark advance provided for 89 (ie. might as well run 87 unless you tow in high temps, or just request the 91+ tune).
The engine tune, after driving 150-ish miles... wow, I like it. Noticeable power increase in the low end (around 1.5k rpms). Feels better across the board. On the stock tune, I was getting random blips of knock retard on mobil gas, even 89 octane. The Diablew engine tune has yet to register ANY knock retard on 87 mobil. Better for the engine, more power, can't complain. The V4 mode was also disabled, though I did not have an issue with V4 (part of the "Cannot notice it's even working" club, which only has 7 or so members on this forum). MPGs are about the same, pedal feel is spot-on, spins the tires too easily (not a complaint, unless its raining)
The transmission tune, on the other hand... it's not bad, but not for me. This was the primary reason why I wanted to tune in the first place, but I am a bit disappointed as a transmission tune made my Colorado (by comparison) FAR better than stock. The tuned transmission on this truck shifts a tad later (which I felt wasn't necessary) and also *tries* to shift firmer. I say "tries" because the firmness is random. When the transmission tune shifts firmly across all gears, I love it. But, the inconsistency breaks it for me. It also does NOT shift faster than stock, or at least not noticeably so. After searching through tune forum posts for this truck, it seems like everyone has had a different experience and probably no fault to Lew as a tuner, just that the truck has a silly transmission. No improvements after 3k miles of driving on this transmission tune, either. Remember that downshift clunk when taking turns around 20-30 mph? Since the transmission now shifts harder, the flaws are more pronounced. I reverted back to stock and due to the additional engine power in the low end, I think it makes the stock tune that much better. Due to the higher shift points, I feel that this tune would make more sense for a truck with the 3.08 gears (vs. my 3.42) as many people with 3.08's seem to hate the shift points. The tune is worth a shot no matter what, but my truck did not like it, unfortunately.
I gave the Diablew TCM tune another shot. After the paint-stick-gas-pedal mod, this tune has definitely improved. Lew says its the adaptive transmission just doing its thing (more the reason to shove something up behind that gas pedal, the truck just performs better all around). The upshifts are much better, driveability all around is "as it should be" and the shift speed is definitely better than stock. Shifts fast and smooth. The only complaint I had was with the downshifting. When approaching a stoplight, the truck felt like it had a less-aggressive engine brake, causing me and my passengers to lunge forward. After asking Lew to modify the downshifts to be less-aggressive, I loaded the new TCM tune and all is well. I have changed my review to reflect that the TCM tune takes some time to adjust, but combined with the gas pedal mod, its totally worth it. Just be wary of how your truck behaves on the downshifts and notify Lew accordingly.
Want more power for only a few hundred clams? Get a Diablewtune. More power than the canned tunes, less knock retard, and will take advantage of engine mods. Certainly try the transmission tune as "your mileage may vary" (har har), but the engine tune alone was worth it. Estimated gains from Lew are 12-39 HP, 10-35 lb-ft of torque, and +0-3 mpgs (all of which are mod dependent). Since I have no mods, I am happy with an additional 12HP/10lb-ft.
Feel free to ask any questions!
Just wanted to throw this out here as I had a hell of a time trying to find any comments on a setup like mine. So I have a 10' Silverado 5.3L. I installed a Volant CAI w/PowerCore Filter, Dynatech Long Tube Headers, Dynatech Y-Pipe w/Cat Delete and Gibson Extreme Duals. I must say I am super excited. This truck now sounds and performs like a truck should. I had it tuned by Diablew Tunes. Lew is awesome very good to work with and even gave me some pointers for a newb like me. I notice a huge difference in performance of my truck. I am looking to get it dyno'd in a couple weeks and will share results. If there are any questions please let me know I am here to help with whatever I can on this setup or something similar.
14 and 15 guys with the Diablo intune, are you satisfied? Im really disapointed with the performance of my new silverado 5.3. For now i have ordered a range device to deactivate AFM and see if that helps. This truck has 3500 miles on it and i HATE to void the warranty but im just about to the point where i dont care anymore. The transmission shifting is horrible, always gears searching, and you have to give it WAY to much gas to get it to downshift from 6th or 5th. Im sure i would get the diablew custom tune with it also. Any reviews are MUCH appreciated. I sold my 2008 tundra for this truck and i felt i have downgraded as far a performance goes so far..
After almost two months of ownership I've finally gotten the bug to unleash a little more horsepower. Here's what I'm looking for guys!
Used Diablosport Intune i1000
Used Diablosport Trinity T1000
Unlock/unmarried from vehicle
Excellent working condition
Good physical condition
Cash In Hand
Disclaimer: While I do appreciate all offers please do not expect me to pay $250-275 shipped for a i1000. They are selling for $280 brand new shipped, a $30 "savings" is not worth it to me on these.
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