Gears

2010 sierra, reverse works , drive won’t engage

Welcome to the forum. 4wd , 2wd, any noises, kinda short of info?

It clicks , when I put it in gear but nothing happens, it just stopped working when I was at a red light , I had just washed my truck, but not under the hood or anything like that 🤷🏻*♂️

More than likely something let go in the trans.

Forward band likely let go. Requires a full rebuild.

Does it function at all in the manual ranges?