4runner trans won't go in Reverse

I have a 96 4runner. Most time when it is put into reverse it will not engage. I have to put it into drive. roll forward an inch or so then put it into Reverse and it works. Some times it works the first try.

A shop said it needed total over haul. Is there a linkage that could be loose.

Help

How long has it been since you've changed your transmission fluid?