Canadian Hummer Club Forums

I currently have an issue with my 2005 H2's transmission where, when cold, it is really hesitant to go in reverse. I was wondering if anyone might have any suggestions? All forward gears work great. Reverse works great after driving for a few minutes and the transmission is warm. It's only when from a cold start below around freezing that it seems to be an issue. When in reverse, foot off the gas and just letting it idle, you can feel a slight surge as though it's trying to go backwards, as if you were backed against something that's preventing it from rolling back. Give it some gas, and the surge becomes more rapid, but not much stronger. I've gone up to about 2,000 RPM like this before backing off. About 30-60 seconds of just letting it idle backwards and it will eventually go. I noticed this a bit when it was around 5 degrees celsius out but it would only take a couple seconds before going into reverse. All levels are good and fluid is looking good and doesn't smell burned or anything. Does anyone have any suggestions? A servo/actuator? Something that might be slow to engage when cold if it's a bit old and worn out? Hopefully something that's external access. Bleh! Any help appreciated. It's not life or death, more annoying, especially since I parallel park at home and getting the vehicle out like this is a pain!

I know from experience that H2 ( they shared a part with 2001 Jimmy's ) will fail in reverse and in all higher gears ( above 2nd) most likely have a failed Sun Thrust Shell (clutch plate basket). So posible sticky clutch plates or this unit is about to go . This part is one of those cheap parts but expensive job to do (300 bucks for part 3000 for job to get to it.)

Apply piston for the reverse band or the band itself would be a guess for me assuming you have all forward gears.

Of course most tranny shops will want to sell you a rebuilt tranny. Im an H1 with a 4l80e, i don't know what the H2 has in it. Perhaps you could elaborate.

Did this happen shortly after a heavy off road trip or have you been cranking it in reverse? If so the sun shell could be cracked but so far i say no.

You mention that when the fluid warms the tranny works normally so i doubt its mechanical and probably valve body for sure so save your 3k for something else. The worst case would be a broken band which would mean renmoval and teardown but if it works after warmup its something else.