Ok I had to back my 92 chevy silverado out of the garage on Wednesday. I started the truck and put it into reverse. usually it makes the loud clunking noise as it shifts. this time it didn't. IT didn't even shift at all. so I continued down into neutral. still nothing. I slammed it pack up into park and tried again. same thing. Then I tried putting some force on it when shifting and it finally shifted. No problems since.

Its a 700R4 paired with a 350 V8

 

Mine did that once last winter but not since. Is it cold where you are?

 

It's Michigan.

It was about 50 degrees on the day that it happened. I talked to my Grandfather and his initial respnse was that they do that when they sit awhile. When I told him that it hadn't sat for more than two days he was stumped

 

That's weird!

 

Hasn't done it since.

Next wednesday I will be driving it across the state to put it in my grandfathers heated shop for the winter. Hopefully come spring it will shift

 

Check the fluid first.

Does it go forward?
If it shifts into drive, then move it back and forthto reverse and drive and see if that will get the slave pistons and hydrolics to free up. Also let it warm up a bit.

If it doesn't shift into any one of drive or reverse, then I would say that you have probably lost the hydrolics and that would mean that you will most likely need it to be rebuilt. But it all depends on what the symptoms are.

Good luck and look at the bright side, if it is blown, it should be cheap to replace! And I would replace it with a used good one from a junk yard. Or rebuild it to be even stronger!

 

I didn't try shifting it into drive on that day, I'll see how it goes and if I have the problem again I'll look into replacing or rebuilding it. It's a 700R4 so I agree they are EVERYWHERE!