305 TC lockup earlier than 350???
Thread Starter
Member
Joined: Dec 1999
Posts: 160
Likes: 0
From: Davenport, Ia, USA
305 TC lockup earlier than 350???
torque converter locks up at around 25 mph in drive. Its seems to lockup too early, and never seems to unlock unless the brake is pressed. If you get into the trottle it never unlocks, if you give it enough gas, it just downshifts. ECM thing? Anything I can do short of unplugging it and wiring it through a switch??
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
What 350 are you comparing it to?
Does it lock up in 2nd, 3rd & OD, or just when it shifts to OD? Is it always exactly at 25 mph?
The lockup is controlled electrically by the ECM. The fact that it unlocks when the brake pedal is pushed indicates at least it's not a hydraulic problem within the transmission. But, if it locks up as soon as it shifts to 2nd, then the wire going to the ECM may be shorted. Or, your PROM may be telling it to lock up at 25 mph - That can be reprogrammed.
Does it lock up in 2nd, 3rd & OD, or just when it shifts to OD? Is it always exactly at 25 mph?
The lockup is controlled electrically by the ECM. The fact that it unlocks when the brake pedal is pushed indicates at least it's not a hydraulic problem within the transmission. But, if it locks up as soon as it shifts to 2nd, then the wire going to the ECM may be shorted. Or, your PROM may be telling it to lock up at 25 mph - That can be reprogrammed.
Thread
Thread Starter
Forum
Replies
Last Post
