pusher_sr

looks like i've got myself another late winter project. there's a clunking (a small jerking) in the shifting of my powerglide. not an actual shifting from low to drive, but as i leave a stoplight the automatic shifting up in gears. there's NO slipping of the bands in the trany that i experienced many years ago (66 chevelle), so i guess something's broke or out of line.
can anyone pass along any tips or information on what i'm going to find once the trany is taken apart. any pictures of the guts of these transmissions would be great. and i won't even ask if this is a big job. i'm gonna presume it is and the driving season is about 4 to 6 weeks away.
i've never attempted a major job like this before so, thanks for any help.

67L36Driver

If you DIY, you need an old "Motors Repair Manual". They have an excellent section on auto trans. Pick one up at a swap meet.
I did a Corvair powerglide several years ago and had no problems. The 'Vair glide is about 2/3 the size of the full size, same difference.

soppeng

There is a copy of Theory and Diagnosis - Chevrolet Automatic Transmissions at the following website. It includes the powerglide. This is the Old Car Manual website.

http://www.tocmp.com/manuals/trans/T...971/index.html

toadster

Is the clunk/noise/jerking when you leave from a stop and it shifts up? Does it sound like a real "clunk"?

dfolse62

Powerglides are simple and can be repaired by most shops. Remember, they are a hot item on drag strips and are not considered old timey. This should be a reasonable rebuild, just don't mention corvette, just say chevy! Parts are available everywhere, don't panic. Good luck! Darrel

67L36Driver

When you belly up to the parts counter just say "Chebby", never admit you are buying vet parts as they are priced much higher.

pusher_sr

it's not a very loud clunk, but more of a little jerking motion. yes, it's when i just leave a stop light, maybe doing about 5-10 mph and the same thing when coming to a stop at a light- on the downshift motion. hope that describes it better.

dfolse62

I don't know a lot about these, perhaps a small adjustment would work. It might be worthwhile to check the vacuum modulator. It screws in the back, driver side. It should have a vacuum line to it. It could have fallen off.

Frapps

Hmmmm, u-joint?

Tom/99

chrisdev

I've got to agree with dfolse62 and Tom99. I had the same thing happen with my PG and it turned out to be a split in the vacuum hose at the manifold fitting.

VFW NO.11548

Yep sorta sounds like a vacuum leak to the modulator,usually causes a severe upshift and downshift, your motor should be running a little rough because of the vacuum leak, you would really know if the modulators diagram is ripped,it will start sucking trans fluid into the engine and you'll swear you lost the rings (smoke)