Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Chevy Silverado and GMC Sierra Transmission Problems



  • lesbolesbo Posts: 2
    I have 2011 Silverado LT with 5.3L and 6 speed. Only 1700 miles so far.

    My experience to date is that the drivetrain is very smooth as is the ride itself. I am very satisfied.
  • I bought a new 2011 Yukon in November, it's the first one I've had with a 6 speed. I've had 5 new Yukons since 2000, I never thought to take it for a test mistake!. Since then I've taken back to the dealer 3 times, they tell me it is running normally. I can't stand it, constantly upshifting, running in V4, hesitating and I'm thoroughly disgusted with it! Told GM that the shifting condition should have disclosed prior to the sale. GM refuses to make repairs, is it time for a class action lawsuit???? Are you unhappy enough to join in? Let me know!
  • chuck1chuck1 Posts: 1,405
    edited March 2012
    You bought a new.....over 40K vehicle and you didn't test drive it?
    1) Yes, it's geared where it will downshift at the slightest hill or passing. This is probably done for fuel emissions).
    2) Yes, it will run in V4 mode-that's what it is designed to do. If you do not want it to run in V4 mode - use the manual selector(have you read your owner's manual-yet) when your in town and shift it to "5". The V4 mode will not come on.
    3) Everything other then the hesitating (not sure what that is) is normal.

    4) Edmunds is not the forum (see rules) to solicit for a lawsuit.

    5) You have no basis for a lawsuit.
    6) Test drive a vehicle before you buy it. Especially when it cost $40,000.00!
  • el_hoppyel_hoppy Posts: 43
    you can count me in. GM still refuses to fix mine. little over a year now and GM customer NO service tells me my transmission is STILL learning and to give it more time.
    GM is a joke.
    NOT a satisfied customer.
  • gmcustsvcsarahgmcustsvcsarah Posts: 1,964
    Good morning alcianfarini,

    I'm sorry to hear that you are not satisfied with your Yukon, and hope to at least provide some information on the systems in your vehicle.

    With the Active Fuel Management system, your vehicle will operate in half-cylinder (V4 will be on the Driver Information Center Display) to improve fuel economy. The system will switch over to V8 when greater power is required (as in instances of passing, needing to accelerate from a stop, or merging onto a freeway).

    For more information on how the transmission operates, I would recommend looking into p. 9-37 in the owner's manual (the section includes information on the Manual Mode that chuck1 referred to).

    If you have further questions, I will be happy to help as best as I can. Please send me an email at the address in my profile.

    GM Customer Service
  • mloeckermloecker Posts: 26
    hahahahhaha-- look at old Chuck go- Really? these transmissions are a complete failure and you will get no where with GM- they don't care about you for God's sakes- don't waste your time and money. If you can't handle the upshifting, etc. Sell it and take a 50% loss. I just live with it and drive in the "M" mode as most of the clunking and shifting issues go away. GM will never dfo anything about these issues unless they pose a safety risk like I've said before and that has not happened to date to my kowledge.
  • adeemadeem Posts: 7
    Is this behaivior also applicable to 2011 GMC Seierra 1500 4x4 pickup? I am facing the same problems with the transmission. I have never felt sorry for buying anything like I am feeling now when I bought this type of car, shame on GMC
  • gmcustsvcsarahgmcustsvcsarah Posts: 1,964

    That's correct - the 2011 Sierra has a similar Active Fuel Management system. The information on that begins on page 9-44 in your Owner's Manual. I am looking and not having much luck finding information straight away about the transmission, but will get back with you after the weekend (won't be in until Tuesday).

    GM Customer Service
  • lstriplstrip Posts: 42
    Your responses are corporate lines. You say you only try to stop all the "half truths" yet here you are again immediately trying to belittle an individual with valid issues that gm will not address. He has every right to be on here soliciting other gm owners such as myself who cannot get satisfactory resolution to our issues. GM KNOWS there is a problem. YOU know there is a problem. you tell the guy to drive in 5th gear like that should be an acceptable answer to the problem. BS! my dealer says, as you have, that there is after market products that will resolve the issue but, will void your warranty. THEY KNOW THERE IS A PROBLEM WITH THE AFM/SIX SPEED VEHICLES. and they refuse to publicly address and fix the problems.
    I gladly will participate in any action against gm on this issue.
    and satisfied "owner" such as yourself monitors a forum on transmission and afm problems just to challenge every post that calls attention to the problem. we have had enough of your less than "half truths".
    if you do not want to be a part of the solution, then please quit being part of the problem.
  • chuck1chuck1 Posts: 1,405
    Disagree. I gave her some solutions (using manual mode for example) so that she could be more satisfied on the 40K vehicle she bought but did not test drive.
  • I own a 2008 GMC Sierra 5.3L 4x4 crewcab, 4spd Trans, 41,000 miles. I haven’t posted in a while but have been checking in, it’s sad to see nothing has changed in the last 4 yrs. This should be a warning to all buyers looking at any GM product. I bought mine 3 months before GM went off a cliff & dealerships were being shuddered & I could chalk some of the difficulties in getting acceptable service to the chaos, sadly nothing has changed. Not sure it all can be blamed on the 6 speed trans either as I see issues now that I experienced in my 4spd. I believe some are programmed better or maybe some have bad sensors of some sort causing things to act up. The one thing that hasn’t changed is GM’s response & customer service. I will try to offer some advice from hind sight to the unfortunate GM victims. My history: I’ve experienced unintended acceleration, clunk/binding or delay between 1-2nd gears, ticking from engine in morning, rough idle at stops, truck will drive itself at a consistent speed of 25mph down a level surface with foot off all pedals, AFM issues that amount to a unpleasant driving experience, subpar mileage at times, odd inconsistent operation of the truck, jeckle & hyde like, never knew what to expect, alignment completely out of whack from the factory.
    After 4 yrs & 41,000 miles of ownership I can report that many of the issues have become non issues due to I suspect it ‘learning” & adapting & me “accepting” & getting used to the piece of crap. I replaced the battery early on which seemed to help the jeckle & hyde inconsistent operation & voltage swings, why I do not know? The unintended acceleration was not fun, I believe there is a glitch in the “re-learn” mode that if left alone goes away, I hope! My dealership just kept “relearning” the trans which in turn caused 90% of the issues including the unintended acceleration to return or remain resulting in a vicious cycle. In hindsight the best thing I did was stop going to the dealership.
    I suffered from all the dealership issues you all have experienced, heard all the same BS “operating as intended”, “it needs to learn” “never heard of that problem”, “they all do that”, & the best one “just drive it you have a 100,000 warranty” blah blah blah This is obviously standard operating procedure at GM dealerships as it continues to this day. Trying another dealership is advised as I found some relief in doing that, best if you can get out of a district managers “zone” since they have a lot to do with these issues, another manager might be more empathetic, don’t count on it though. Regardless of what happens to my truck, warranty or not, I will never step foot in another GM dealership or service bay, the cons outweigh the pros.
    Due to the unintended acceleration issue & transmission flaw at 3,000 miles I tried The BBB arbitration method to get assistance, a buyback, whatever. In MN. you need 3 unsuccessful attempts at a repair before you can sue. I went through the process which is nothing more than a fake, rigged system. Get this, I was told that the repair made to the transmission was never really made; they had lied just to appease me & make me go away. I based my case on documentation that turned out to be a lie & they still won through arbitration. If you truly have an issue so severe that you need it resolved than I suggest getting a lawyer & doing what you have to do, in hindsight I wish I would have, I had the confession of GM rep on tape saying they lied about the repair! Makes me sick to my stomach recalling it all, I do not wish that process on anyone.
    Save yourself some sleep & your mental health & stop banging your heads. 1st & foremost GM will not fix your “operating as designed” trucks, they wont, it sucks but just accept it. Is that right, hell no it isn’t but save yourself the headache & get a tuner or better yet find a “speed shop” that is reliable & have them put it on a dyno & tweak the truck to your liking because I guarantee GM wont. Will it void the warranty? Likely, but I have heard you can swap out the programs back to stock, not sure though. The way I look at it if GM wont help you right off the bat with an issue on a NEW truck it is highly unlikely you will get them to stand behind their product at 60,000- 90,000 miles so why suffer with drivability issues on a new truck worrying about a warranty that is worthless, just my opinion. In hindsight I wish I would have tuned mine.
    Adding extra weight to my bed helps mellow out some of the drivability issues, I’m assuming they are tuned more to be used as a real truck then a grocery getter, this would benefit GM as it would result in less wear & tear when actually used as a truck. My AFM seems to work as intended, it is far from flawless though & is very cumbersome & takes some getting used to especially when turning after slowing down & in town driving with it just sucks, period. I average 15-16 mpg with mixed driving & 17-19 on the highway at 65-75 mph. On the highway this truck is nothing but a joy to be in. To me the AFM seems like a flawed system as my buddy with a 2005 Sierra without AFM consistently gets 19 -22mpg on the highway. There are tuners out there that enable you to deactivate the AFM, I am guessing if you disable it that many of the other issues with the truck would also disappear; in hindsight I wish I would have tried it myself.
    As mentioned none of this is acceptable after plunking down the big bucks, your options are limited if you are unfortunate to buy one with these issues. You can sell it, go to court, void the warranty & tune it, find a good independent mechanic or just live with it. All the logical good business practices such as taking care of the customer, standing behind a new product ect.. do not exist at GM, it is a numbers game, regardless if you are the best GM customer they have ever had, you are just another sucker than fell for the lipstick on a pig. Do not try to use logic or common sense in trying to deal with GM it will just mess you up even more. Tell your friends, keep posting here, write a review & most importantly do not ever buy another GM product, it’s all you can really do. Good luck to all!
  • chuck1chuck1 Posts: 1,405
    edited March 2012
    They shuttered under performing dealerships, which it seems you experienced.
    I have heard (but can't verify) that the Diablo tune will not leave a footprint on the truck's ECM if you need to change back to stock for a warranty visit.
  • Chuck, thanks for posting the link to the tuner, I hope it helps some of the people experiencing some of the issues I experienced going back to the 08 model. I chose not to tune mine because 1 brand of tuner would solve the AFM issue but not address the tranny shift points & vise versa. I still believe if a tuner is used to disable the AFM that many if not all the other funky issues with the transmission would disappear, I'm not a mechanic though. The point of my small novel was to let people know that these issues are not new with the 6 spd tranny & that GM's response today is identical to what I experienced in 2008. I do not wish what I experienced on my worse enemy. I offer some solutions from hindsight to help people get past the anger & emotions to find resolution to their truck issues because I guarantee GM is not the solution, been there done that! Good luck to all!
  • I have the same exact problem and I keep getting blown off by 3 different service managers. Just send a certified letter to Daniel Akerson, CEO of GM. Let's all hound him until we get our tansmissions fixed!
  • obyoneobyone Posts: 8,054
    Ditto with Hypertech
  • chuck1chuck1 Posts: 1,405
    "these transmissions are a complete failure"


    While the power train does have some issues, no one here has said their truck has left them stranded. The transmission will go on doing the job and the truck is a joy to drive on the open highway and you can achieve 20 mpg on the highway. This is documented if you do a google search.. Are there issues? Absolutely, but by no means a "failure".
  • Chuck, you are funny! I appreciate that you took the time to read my very long post & for providing the link to the tuner info but please do not be a hypocrit spreading half truths by selectively using a 12 word sentence out of a 2,000+ word post. I posted 1 positive sentence & you ran with it & ignored the rest? Thats a half truth! Yes my truck is a joy to ride on the highway, too bad I'm not an otr trucker. Have you ever experienced unintended acceleration or a truck that changed the way it operated on an hourly basis? Ever been screwed over? Unless you have experienced the emotions of being stuck with one of these flawed units after investing $30-$40,000 & then asking for help from the business only to be spat on I am not sure you can relate. Poking sticks at people isn't really offering a solution or help, your replys have the same tone, additude & message as one coming from the dealerships & GM. I appreciate your dedication towards wanting an honest discussion & offering another point of view, emotions create drama, it doesnt mean they are spreading half truths, it is far from a 1/2 truth when it happens to you. If your goal is to add a positive to a negative to tamp down what people see, it's not working. Each time you reply you keep this thread at the top of this forum & in google keyword searches, front & center for all to see, something to think about as you may be defeating your purpose.
    There are only 5 solutions to offer anyone with these GM transmission issues, here they are again: you can sell, sue, tune, independent mechanic, or live with it. Please note GM is no where on the list, stop banging your heads people!
  • I picked up my 2012 sierra 1500 SLT two weeks ago. At 384 miles on my way home l;ast night I was driving up a short incline when the TAC pegged and the truck slowed down and started to drift backwards in "D". I applied the brake, put it in "P" then back into "D" and the TAC pegged again while drifting backwards. Put it in "M", no difference. Tired "D" and 4x4H, still racing the engine but drifting backward. Finally had to have it towed to the dealership at 384 miles. The service manager said he has never seen anything like it ........
  • 49chevy49chevy Posts: 5
    I got the last GMC Owners magazine and the highlight was the guy who designed the 6 speed transmission and fuel management system combo which was supposed to give better mileage and a better experience. I hope he sees this post, cause he cost us a lot of aggravation and expense for something that does not work! After seeing in this forum the comments about using M5 and the constant changing of the fuel management system to V8-V4-V8, I decided to give it a try. Putting the display in Instantaneous mileage, you get to watch the system constantly change the system from V8 to V4 and what looks like better fuel mileage. Now put the transmission in M5 and it stays in V8 mode. Gone is the hesitation on acceleration and it now feels like my old 2000 truck. My average Fuel mileage up to this point was 17 MPG. Using M5 I am getting 17 MPG also. Where is the benefit? Get rid of the hesitation, go to M5!
  • gmcustsvcgmcustsvc Posts: 4,251
    I apologize for your frustrations. Can you please email me with the name of your dealer and VIN? I would like to look into this further. I look forward to hearing from you.
    GM Customer Service
  • VIN# 1GTR2WE78CZ244313

    Fred Beans GMC, Doyelstown, Pa.
  • gmcustsvcgmcustsvc Posts: 4,251
    Please keep us updated on what happens at the dealer. I look forward to your response. Please fee free to email me directly.
    GM Customer Service
  • super6sierrasuper6sierra Posts: 6
    edited March 2012
    Original post:
    "I have a 2009 with a 5.3l, 6speed, 4x4, 3.42 rear end. It came with the Z71 package and has the 18" wheels. I have been having problems with the transmission and I am wondering if anyone else has experience similar problems. 55k miles.
    Here is what happens.
    When I pull away from a stop, it shifts very, very quickly (under normal driving, when I hammer on it, this doesn't happen) down into 2nd and third goes to 2nd before I even make it through the light. So, when I want to then bring it up to speed, it is already locked down into usually 3rd and wants to stay there unless I go past probably 3/4 throttle, at which point it jumps down violently to what feels like 1st. Seems like it is tuned very, very aggressively for mileage. Very, very annoying as it does that all the neighborhood/slow speed city driving really stinks. Tranny is very confused. If I put it into tow/haul, it stays in gear much longer and there is no issue. Seems like it might be tuned for an engine with much more torque or a 3.73 or 4.10 rear end.

    2nd. When slightly rolling (1mph or less) and then trying to accelerate, there is a slight 1/2 second delay, then the power kicks in and everyone's head jerks back. I have to be very, very, very gently on the pedal and feather it through this until the engine/power engages. This seems like it might be a throttle issue or something to do with the fuel delivery. Does this truck have a throttle cable, or is it electronic?

    3rd. Problem. Towing. Under hard acceleration (not w.o.t., but well past 3/4 throttle) and towing 2k--4K trailer, there are multiple times where the tranny "jumps" or slips in between 2nd-3, 3-4, and 4-5. Engine revs slightly and it jerks into gear. Again...seems confused.

    I have had this truck to the dealer for warranty work on tranny. There are no codes. They could find nothing. I explained everything to my dealer as I have in this post. It is due to go in again. I checked tsb's and couldn't find any that seemed to be related to the issues I am having. HELP"


    This is not normal and after 2 more trips to the dealership they can't help me. They can feel the problem and have verified that there is a problem but the computer doesn't kick out any codes so no help for me. Problem is still there and if this is "normal" they GM had a lot of work to do. They gave me a 2012 to drive as a loaner. Same engine 5.3l. Same 6 speed. Same 3.42 rear end. Totally different truck. No issue. Way way way better. To bad there aren't any updates for tuning my tranny. I want to get rid of this truck. Nicest truck I have ever owned. Really like it. Engine is fantastic. Interior is great. Tranny is horribly tuned. GM customer service pretty much said there is nothing they can do. Anyone have luck with an after market tunes? I like Banks. Anyone try their stuff with this combo (stinger system). Thank you very much.
  • chuck1chuck1 Posts: 1,405
    edited March 2012
    From another source- 2012 truck 5.3-6 speed-Some problems same as yours-

    Anyway, the latest on my tranny. 1st time they replace valve body. The 2nd time in they replaced the TCM per GM, but a higher up at GM told the service tech that it could likely return because it is a software issue and they are working on it. So far it has not returned.

    Maybe your dealer is not trying hard enough.

    The Diablo tune is very popular.
  • Dealer diagnosis - a failed selenoid, but one that is in a current allotment "series" known to have a small current failure rate for 2012's.

    Part recommended by technical assistance is on order by the dealer with an ETR of Thursday 3/22/12 ......

    The scary part is that it fails while underway and in use - could be on an interstate, steep uphill grade, etc with no warning signs .... I was lucky I think, that it failed how and when it did.
  • gmcustsvcsarahgmcustsvcsarah Posts: 1,964
    I'm glad to hear that they were able to diagnose your Sierra, bikerandy, but wanted to apologize that this situation came up so soon on your 2012 vehicle. Again, please continue to keep us up to speed on what's happening, and we're happy to assist if you should need us!

    GM Customer Service
  • I have a 2010 silverado 1500 same drivetrain etc. Same problems, which didn't begin untill 10,000 miles. My local Chevy dealer says they cannot find any problems, but REALLY?? This thing drives horrible now! I dread getting behind the wheel of the truck which I absolutely loved the first 10,000 miles. This is frustrating because there are so many posts claiming the same problems and once again, the dealerships play dumb! My 2004 Silverado gave me the same problems and I got rid of that with only 18000 miles on it. Guess it's my fault for trusting Chevy again...
  • gmcustsvcsarahgmcustsvcsarah Posts: 1,964
    Good morning frankie15oct,

    Reading your post, I can see how frustrating it would be to see similar issues arise in a newer vehicle that you had seen earlier. If we can look into this further with you, please get in touch via email ( with more information, including your name/Edmunds username, phone and address, the last 8 of your VIN and current mileage, and name of your involved dealership.

    GM Customer Service
  • I can sympathize with how you feel. I've had my 2009 LT 5.3L w/6 speed since I bought it in October 2009, and have put now almost 32,000 on it. Up until about 30,500-31,000 miles everything was fine and I've loved this truck. Best all around truck I've ever owned...until now.

    Over the past month, I had it into the Dealership twice, for a total of 9 days. It started with the transmission seeming to resist moving when first put into drive whenever I stopped. That was minor and I let it go for a month or so until it started doing other, more serious things.

    It began to stutter and shudder when shifted from reverse into drive. Sometimes it would not even go into drive until I shifted back and forth from drive to park to drive again. Sometimes it would then lurch into drive with a bang. When this continued to get worse and worse, I took it to the dealer. They had it for 5 days and told me that they had to replace a carrier bearing and almost all the planetary gears and returned it to me. The very next day, it started back doing these things again.

    In an attempt to keep from doing more major damage as described to me before, I took it back in. But only after having been belittled by the service coordinator with mentions that they cannot do anything unless it repeats while the mechanic is in the truck with me. After three calls like this whereupon it was intimated that the problem might not be real, I had enough and had to berate the service manager to get them to take the truck back in to look at again.

    They claim that they can find nothing wrong with it this time and, even though I was able to reproduce a minor version of the shuddering the day I came to pick it back up again, still want me to drive it while they "contact engineering and see if this has ever happened to any other trucks."

    This was two weeks ago and calls back to the dealership get me nothing except comments that it won't hurt the truck to drive it like this and if something serious happens they will tow me to the dealer for free!

    So the bottom line is that I am now being soured on the truck that I planned to drive for 200,000-300,000 miles and now have issues with every day, but must apparently wait until it breaks down before I will get any more attention to it.

    This is doubly sad for me as I have always had my best luck with GM vehicles in the past and currently have a 1997 Pontiac Bonneville my wife drives, that has 218,000 and runs like a top with nary a transmission problem its whole life.

    This is not how it should be.
  • gmcustsvcsarahgmcustsvcsarah Posts: 1,964

    If we can follow up on this with you and your dealership, please send more information (your name/Edmunds username, address and phone, last 8 of your VIN and current mileage, and the name of your involved dealership) to and we'd be happy to look into this further.

    GM Customer Service
Sign In or Register to comment.