Hi all,

My Tahoe 2007 Flexifuel has had two incidents with the reverse drive not engaging.
First time I just shut off the engine and started it up and it worked again.
Second time the restart didn't work and I got the idea to bring the engine up to 2000 rpm and slam the reverse in, after that the reverse worked again!
I did an oil change yesterday and the trans works OK now but does anyone know what the issue could be?
My thought is that there was a lot of filth in the oil since the trans oil was almost brown and the filter looked to be full of filth.
No metal junk in the oil pan so I'm thinking it could be some valves clogged with filth so the reverse can't engage?

Has anyone had this happen?
Renovating the transmission here in Sweden is crazy expensive so hoping this oil change will resolve the issue for now...

Thanks Thomas