Transmission problem
1995 Chevy Cheyenne V8 Two Wheel Drive Manual 220000 miles
----------------------------------------------------------------
I have this truck with the 6.5L turbo diesel and the NVG4500 5 speed transmission. I and my mechanic have spent hours trying to get the clutch to dis-engage once the truck has been driven a while. The problem appears when the outside air temp is over 70 or 75 degrees and after the truck has been driven more than 30 minutes. Sometimes the problem will not occur with one individual instance where the clutch is used; but most of them time it does. When it does show up, vigorous, rapid pumping of the clutch will usually cause the clutch to dis-engage. Once in a while, I simply have to shove the transmission into gear. We've tried the "pedal method" to bleed the clutch as well as taking the slave cylinder off and manually squeezing its pushrod into the cylinder it will completely force air out of the system. The clutch was replaced three years ago and inspected one year ago. No problems. The bell housing was broken (who knows how that happened) and had to be welded back together. All of the bearings, fork, pivot assembly, etc. have been replaced. The clutch master and slave cylinders have been replaced twice and the hydraulic line between the two has been replaced. Any ideas? Is there any way to discard this hydraulic stuff in favor of a mechanical (cable operated) system? Thank You!