kolk88

[kolk88]

My 88 GMC 2500 4x4 Automatic occasionally emits a grinding noise when I put it in reverse. Its the kind of sound that you hear in a standard if you let the clutch out before the trans is engaged. when it occurs, I put in in Drive, move forward slightly, then put it back in reverse and it seems ok. During the last week I've noticed that it now occurs when I'm driving on the highway and let off on the gas, sometimes, but its getting more frequent. I've checked the linkage, 2WD and 4WD with no luck. I brought it to a trans shop, they thought it was the planetary gears in the trans, I'm not convinced, any advice?