Yukin Hybrid Transmission/Planetary

[JD Derryberry]

I have an '08 2 wheel drive with 123,*** miles on it and the other day it had a huge loss of power, felt like the trany was slipping at first but engine wasn't revving, in fact the engine wouldn't rev at all while this was going on. I stopped doing it but wouldn't go into autostop afterwards but and the wife got home okay. I called a dealer and they asked to bring it in, on the way there pulling up to a stop sign it made a lunging motion and a banging sound and the motor died. She started it back up and the engine light was on after that. Took it to the dealer and 3 different techs drove it and it wouldn't act up. The code was for loss of power or something like that. The lead tech there is a planetary on the back of the transmission and he is suspecting that is what is going out.

Has anyone out there had this issue or heard of anything like this? Also what kind of mileage should I be looking at getting out from under this thing with the hybrid system?

It had an issue like this one other time and I took it to the same dealer then. They said there was a service bulletin out on an issue with a valve cover gasket leaking and burning out some of the plugs on it. They fixed whatever and it ran noticeably better and hasn't missed a beat since this.

Any info would be helpful.

JD

 

[jprevost]

Yes. The transmission is a piece of crap. I had to replace mine with a new transmission. Turns out that the big magnets in the motors collected all of the metal from the shims inside the planetary gear sets. Seriously, it was a complete scam. The transmission has issues and GM knows it, hence no 2nd gen. They HAD a 2nd gen transmission being dyno tested out in Indiana... and no good.
I'm confident, as an engineer, that they didn't understand the impact forces on the pinion gear shims from the electric motors and/or a mis-fired engine going between v4 and v8. Turns out the transmission is not durable in that way.
Good luck. I had to spend $$$$ to get the transmission swapped and it still has a leak and a burns oil during highway mode. I'm going to figure out a way to retrofit an oil collection system from the PCV system. If that helps I'll be happy, else I'm buying an electric car to keep the miles down. Real shame. This has been a great vehicle for the money. Bought it used for under $30k high miles. The battery is still in great shape because I bought it will a lot of miles. Turns out the transmission was not happy with the miles
Wishing you the best.