What can I say, it worked one day, and didn't work on the next. The problem is it is like it is in neutral when it's actually in reverse. It seems to work intermittently in which case it drives the truck in reverse but seems to be slipping when it does work. It will sometimes immediately work if I put it in R, while other times I have to leave it in R for quite some time and simply wait for it to engage, while other times revving the engine and/or pushing the truck back will make it start to creep backwards. Forward gears seem normal. No weird noises at all, and fluid is not burnt. One shop simply diagnosed "needs transmission rebuild or replacement" but it wasn't my usual shop - I'll take it there in the coming weeks to have them do a diagnostic and perhaps a more in-depth investigation of the issue. I don't have any money right now to do the diagnostic. It will be interesting to see what exactly the issue is and how much it will cost to repair, next time I get paid. As a replacement vehicle my friend sold me his 2002 GMC Envoy SLE 4x4 with 186K miles for $3500 and is giving me 90 days to pay for it. Good friends are amazing. But I will post a seperate thread on that one because it has a few things it needs that I will address over time. As long as that 4L60E doesn't crap out too! Maybe that one will lose all forward gears and still have reverse so I can combine the two... just kidding. In all seriousness I am very frustrated with GM regarding the Colorado. It is a base model 2WD truck that doesn't even have a hitch - so no towing or off road abuse. I'm not the original owner but I have owned it for about 10K miles/10 months during which time the transmission has been perfect. I've posted this on a few other forums - mainly I wanted to post so I can keep the situation updated as I learn more about what exactly failed, and in the off chance somebody has any idea what might be wrong or why the transmission failure prematurely. If this Colorado was my first GM product I would certainly never buy or recommend another. I do really like and have owned other GM trucks and my experience has been positive, but they have all been older. I guess the right way to put this is "they don't make them like they used to".