Classic/Antique Car Repair: 55 Bel Air Powerglide Slipping badly, throttle linkage, winter storage


Question
This past April, after taking my '55 (6cyl) BelAir aout of winter storage, I noticed  slippage on all upshifts (0- to the first shifet at approx 10mph was fine, shifts beyond took 10- 20 seconds to slip into gear.  It seems that by feathering off the gas pedal during the slipping, I could get an upshift a little faster. Never had slippage at any time and it was fine when I put the car in to winter storage in November. I have topped off the fluid.  Is it possible a tranny fluid and filter change might do the trick.  How does one adjust the bands on this van..Your suggestions are greatly appreciated.  Peter

Answer
I doubt very much that a fluid and filter change is going to help.  You can adjust the low band to see if that helps, but if not, I suspect something has happened inside the transmission, either a particle of crud has found it's way into the valve body, or some seal is leaking badly.

To adjust the band, find the adjuster screw on the driver's side of the case, just about 2-3 inches forward of the round dome shaped piece, and about half way from the bottom to the top of the main case.  With the engine off, Loosen the lock nut, then turn the screw in until you feel some resistance, then tighten it to 6 ft lbs with a torque wrench, then back off exactly 3 whole turns - this is the right setting for the early Powerglide.

While you're underthere, make sure all the throttle linkage is connected - as that will affect the shift if it has fallen off, and that's a pretty common thing to happen.

Dick