New GMC/GM 8 Speed Transmission

cw41

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I posted an earlier thread on the GM 8 speed auto and if others have issues with shifting, shudder,etc. After the fifth service visit, mine was replaced and is worse than the original. I was supposed to get a new transmission and torque converter but not according to the service ticket. Thanks for any posts to help.
 

stu

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Keep after the service deparrment.
 

cw41

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thanks stu and I have. lemon law is going to take over. they cannot fix this 8spd?? going to try the 10spd as they have been out for over 3yrs and ford uses the same tranny. we'll see.

has anyone had issues with the 8spd and had them actually fixed?? I see that the general is being sued over it?
 

Mealticket

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This probably won't be helpful but I just saw GM's response to the class action lawsuit on the 8L90 and 8L45, which is what I assume this thread relates to, and am totally sickened by it. One of their arguments is that their warranty only covers defects in manufacturing, NOT in design. Wow. Another is that the complaints don't prove that the vehicles are unfit for use, and another is that there are no allegations of accidents or injuries. Remind me to never buy a GM product again.
 

NickD

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Also hearing a lot of complaints about the CVT, continuously variable transmission, been used in snowmobiles for years, but for road vehicles using a steel instead of a neoprene belt, gather that steel grabs and jerks where neoprene is more flexible.

Have a six speed AT in my Elantra, Shop manual doesn't even discuss rebuilding the transmission as my old 2010 Cruze skipped this subject as well. Guess they are just replacing the entire thing now. Tells you how to check the fluid, be prepared to have hot fluid poured on your face, dipsticks are history.

Some are checked hot, GM has been mostly cold, but if check hot the way this stuff expands, will pour our, and if you plug it hot, when it cools, will be low.

8 speed, recall the Powergluide 2 speed? Wondering if these new engineers can even count to 8.
 

NickD

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Oh, what the CVT shares with this 8 speed, replacing it with a so called new one, still has the same old problems.

My six speed is constantly up and down shifting, some idiot thinks it will get better fuel economy, in 5th gear driving at 20 mph while the engine is lugging like crazy. But at least it has a manual override so I can lock it in a low gear and the fuel economy meter is showing better mpg.
 

Mealticket

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Yes, and I don't want to hijack this thread too far off topic, but my belief is that auto trans technology has, in many cases, not kept up with the need of the automakers to continue to produce more technologically advanced vehicles, no matter what. Evidence Ford's mess with the DPS6. It looks like maybe there is a settlement on that, whereby Ford buys back the vehicles, as no solution exists on that tranny, and apparently production workers say these were broken on initial drive-off from the line. It looks like Ford's statement from the settlement says that no evidence of safety issues exists, but that they settled due to the inconvenience to customers, which is different from GM's stance on the 8-speed. Re: CVTs, it's interesting. I have the Jatco JF011E in a 2007 Sentra. These are known for bad flow control valves in the pump, which can result in damaged variators, and I believe that Nissan significantly extended the warranty on these, but I now have 200K on my car, 160K of which I put on myself, without a hint of trouble. This tranny is also used in Dodge Caliber; I think they call it the CVT2. But apparently the track record is not great, hence the Nissan warranty. I'm pretty sure parts availability is an issue on that tranny. I noticed that somebody is grabbing EVERY JF011E from my local Pick 'N Pull right away.
 

cw41

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Lots of crap being built over the years and shoved down the consumers throats with little recourse. I hope that is going to change but it will take years to see it??
I never had such a technoloigly advanced tranny shift so bad. POS!! Not only is the tranny an issue, but the entire drivetrain is being rimracked when you get slammed in and out of gear. Never been on a rodeo bull before meeting this one.
I hope the 10spd's have most of the bugs worked out.
so far I see good things on them and hope it will last. how many more speeds do we need??
 

NickD

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If there was any kid on block to learn about the latest recalls or fixes for problems was both my GM dealers in town.

Just doing a quick search on this problem revealed this:


Fluid is "Mobil 1 Synthetic LV ATF HP fluid" Seems to run about 11 bucks a quart, Fluid in my Elantra is 13 bucks a quart.

Whenever I had problems with my GM product, had to find the solution on the net, print it out and give it to my dealer. "I didn't know that."

Three service dealers did not know the way to adjust the rear disk caliper brakes was to work the parking brake handle. This is only one example.
 

cw41

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they did the fluid flush one time and eventually replaced tranny. no mention of torque converter or flush coolant lines?? the so called new unit shifts worse than the original. Not bad enough for the computer to set a code though but I'm sure gm has it programmed that way.
I wouldnt touch a 8spd gm with a 50' pole.
 
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