A quick test of the linkage adjustment would be to engage the reverse shift position with the vehicle stopped, engine off. The driveshaft should lock. That's how Hydramatics have a "park" position. If the vehicle will roll in R with the engine stopped, adjust the linkage until there's a good "park" engagement. With the engine running a hydraulic lockout keeps the parking pawl from engaging.
Reverse is engaged by applying the front band and the rear cone clutch. Slippage of either one can result in poor or no performance in reverse. You need to perform two "stall" tests to determine if there's slippage.
1st. gear stall test: Engine running, brakes locked, shifter in "L" or "1" position- - - - -go to full throttle for a couple of seconds. The RPM should not go above 1900. If it does, adjust the bands.
If the 1st. gear stall test passes, move the shifter to R and kick the throttle open. A good 1st. gear test and >1900 RPM in R indicates a slipping cone clutch- - - -transmission overhaul time!
Jerry
BTW- - - -the 1-2 shift happens almost as soon as the vehicle starts rolling, so a slippy front band might not be obvious in normal driving without a stall test.
Jerry
