Hi all
i have a 2006 GMC Sierra vortec max. I swapped the 4l70e for a 4l80e nearly a year ago. When I did the swap the 80 had about 20,000 miles on it and my truck had about 150,000. The swap has performed flawlessly for about 20,000 miles in my truck now ( total of 40,000miles on the rebuilt 80e)

The truck has recently had a maf code (p0101?) and a p0894 code. As of more recent it also has a p0741 as well.
we dropped the pan at a friends shop and the fluid was a bit on the burnt side but there was no metal or anything in the fluid. We put the scanner on it and the torque converter shows slip of >150rpm driving on a flat and >300rpm on an incline. Only slips when the tcc is enabled.

i hauled my travel trailer this weekend for a 120 mile stretch and left the trans in 3rd, tow haul mode and it seemed alright driving wise but the torque converter definately seemed to flash quite a bit.

where should I go from here? I’d really hate like hell to pull the trans to slam a new torque converter in..is there something else you guys would recommend before hand such as a tcc solenoid replacement? Pwm valve? Somethings like this?
If I have to put a converter in the thing it’s not the end of the world.. was also going to see what you may recommend for a towing converter. I’m out with my travel trailer a fair bit. 7000lb+, and the truck will get the 212/218 cam I have installed this winter.
any help would be greatly appreciated thanks

 

You fixed the MAF problem first, right?

 

We had thrown a spare in with no luck, but I’ve got a new Delphi unit that I’m going to try to install today

 

I know it will bang the 1-2 shift when the MAF fails, I was thinking maybe MAF problems can have other effects on the trans.

 

But then it wouldn't throw trans codes...

 

Changed the maf today, seems to have made a difference. Shifts definately cleaned up a lot and I haven’t had any codes come back. Made a 200 mile trip today on the highway and everything seemed good.
going to monitor it for the time being and reevaluate my options if it does get worse. Camping seasons almost over with so I may as well leave it for another month anyhow lol

 

P0894 code will bang the 1-2 shift until you clear the code. Once the code is cleared it will shift normally until the code is set again. I had this issue for a while then I lost 4th gear then it wouldn't shift 1-2. Fluid was burnt and the converter was toast.

 

On a 4L80E as well?
what did you end up doing afterward? Full trans and torque converter on it?

 

yes, p0894 will cause harsh shift on 4l80 as well until code is cleared. I ended up buying a new trans and converter.

 

Well I’m back lol, took the truck 200 miles out of town for work and it was decent for about the first 50 or so.. now all shifts feel like your getting rear ended .. don’t get it. I also pulled the batt cables when I did the maf to clear the p0894 code..now currently doesn’t have any codes at all.. what gives?