Transmission problems with Sierra/Silverado

[ToJo]

Someone told me that GM has had problems with the automatic overdrive transmissions on late model Sierra/Silverado 1500 trucks. I have a 2006 Sierra and I would like to know if there is something I need to be aware of or do to prevent a problem.

[az'03Silverado]

I'm not aware of any problems. My '03 has 40,000 miles with no problems at all. But, the usual answers, keep the fluid checked/changed, drive sensibly, use tow/haul mode when needed, install a trans cooler (if you don't already have one) for towing. Should be fine.

[ZZebes]

the 4L60E had problems with cracking the sun gear housing, thereby losing 2 and reverse i think

 

i talked to a tranny guy i know and he told me that they redesigned the sun gear shell in 04 i think to attempt to prevent crtacking

[ken1mod]

Nope. Enjoy your truck and perform the recommended maintenance.

 

Ken

[RyanZ71]

I've seen my fair share of folks on here who do have tranny problems with the 99+ trucks (not sure about 98 and older) my truck has a problem with the tranny as well, been doing it for the past 30,000 miles. I'll be driving at highway speeds (65 MPH+) for about 15-20 min when for no reason I will loose overdrive. If I take my foot off the gas the RPMs drop to idle (not supposed to do that when vehicle is in gear) After about 3-4 min it usually comes back to normal conditions. I think I had the same problem on my old 94 Pontiac Grand Prix Would loose overdrive for awhile and then it came back. I've had the tranny serviced since then, didn't seem to help any. It doesn't always do it but is most noticable on warmer days.

[Nice rig]

 

My truck does the same thing, shifts funny into overdrive on occasion.

[RyanZ71]

It would be nice if it was a software issue, because then I *might* consider holding onto my truck a bit longer.

[RyanZ71]

Speaking of which, has anyone ever had to have their truck computer reprogrammed for a transmission related issue?

[mcreyaufmiller]

Sorta, I have 2 tunes, a 87/89 and a 91/93 tune from jesse. When I install the 91/93 computer, the tranny slips like crazy! I currently run the 87/89 tune and am building my parts stock until I have the complete tranny in parts before I tear into the old one. As far as the OD problems, I would look into the TQ converter. Sounds like it is not working properly.