[C2] Powerglide problem
Thread Starter
6th Gear
Joined: Apr 2020
Posts: 6
Likes: 0
Powerglide problem
Hello, I am trying to figure out what is wrong with my 2 speed Power glide trani in my '66 327-300 hp. When first started and driven, it takes about 15 mins before the trani will shift from 1st to 2nd. Warming the coupe up doesn't help. It does not pull, 9attempt to shift) but once it finally shifts, it will shift just fine all day long, unless l let it sit for to long. If so l must putt around again before it shifts...Any ideas guys? l do not think it is a vacuum problem. Any help is most appreciated.
Safety Car
Joined: Aug 2000
Posts: 4,148
Likes: 642
From: Bandera Texas
Are you sure the fluid leval is correct? If the convertor is not full, it will not shift correct. I sugest changing the trans fluid.
Lnkage adjustment may be necessary as well.. READ UP ON THE OPERATION ON MANY WEBSITES
LIKE https://ls1tech.com/forums/automatic...anny-work.html
Lnkage adjustment may be necessary as well.. READ UP ON THE OPERATION ON MANY WEBSITES
LIKE https://ls1tech.com/forums/automatic...anny-work.html
Last edited by jimgessner; May 5, 2020 at 08:10 AM.
Race Director
Joined: Apr 2005
Posts: 11,310
Likes: 2,160
From: Bowling Green, Kentucky
Agree with Jim on the fluid fill. These old trans also had a band adjustment that should be done periodically. I believe they also have a vacuum modulator........which may be faulty or going bad.
A few things to check. The factory service manual should/will have details.
Larry
A few things to check. The factory service manual should/will have details.
Larry
Safety Car
Joined: Aug 2000
Posts: 4,148
Likes: 642
From: Bandera Texas
Agree with Jim on the fluid fill. These old trans also had a band adjustment that should be done periodically. I believe they also have a vacuum modulator........which may be faulty or going bad.
A few things to check. The factory service manual should/will have details.
Larry
A few things to check. The factory service manual should/will have details.
Larry
Melting Slicks
Joined: Jan 2007
Posts: 2,842
Likes: 623
From: Pasco Florida
You might try disconnecting the TV rod that goes down to the transmission at the carburetor. Be sure to secure the rod so it can't interfere with the carburetor or linkage. Then test drive when cold.
Another possible test when cold is start out in manual low gear, then shift to drive at around the normal upshift point.
The results may help others diagnose the issue.
Another possible test when cold is start out in manual low gear, then shift to drive at around the normal upshift point.
The results may help others diagnose the issue.
Racer
Joined: Nov 2003
Posts: 430
Likes: 60
From: Central KY
Pull vacuum hose off modulator valve and check for trans fluid (if present- bad valve). Replace vacuum hose and modulator valve. Cheap start to solving problem.
Last edited by itsforfun; Jul 14, 2020 at 01:41 PM.
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Hello, I am trying to figure out what is wrong with my 2 speed Power glide trani in my '66 327-300 hp. When first started and driven, it takes about 15 mins before the trani will shift from 1st to 2nd. Warming the coupe up doesn't help. It does not pull, 9attempt to shift) but once it finally shifts, it will shift just fine all day long, unless l let it sit for to long. If so l must putt around again before it shifts...Any ideas guys? l do not think it is a vacuum problem. Any help is most appreciated.
The aluminum glide is fond of staying in first longer than seems right after a cold start and first take off. My 63 Impala, same transmission does similarly except when it does mine will up-shift when I come off throttle. Will yours? If so I would say it is normal operation. If you cannot get to high until it warms up no matter what you do I suspect a sticky governor or hardened seals, which would be unusual. The Powerglide is a conundrum of a transmission. Built to be as cheap as a transmission can be it is also the most reliable mixer ever made.
The low band adjustment is probably not involved. It and low fluid level present as up-shift flair and low speed slippage. But it is good to perform the adjustment and verify fluid level, car hot and level. Also make sure the modulator and vacuum source are operable and without leaks. The shop manual will walk you through what else you can do to this box in the car.
Dan
Last edited by dplotkin; Jul 14, 2020 at 02:46 PM.