Auto trans-Lock up tip
Thread Starter
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Auto trans-Lock up tip
Lock up torque converters are a great thing.
They allow for better gas milage, sometimes 3 or 4 mpg
They allow rpms to drop 2-300 rpm
Temps in the trans drop like a stone.
The ecm looks for a few things, then it commands lock up. The pressure switches in the valve body look for the pressures required and normally complete the circuit. This allows for the lock up solenoid to activate, opening a mechanical valve in the pump. This valve permits fluid to the converter to lock up the large plate inside. It then allows for the converter to go 1:1. Zero slippage internally allows for the good things I listed at the top of this page.
Failures in the lock up circuit should be corrected asap. Repairs are typically very inexpensive.
To test for proper lock up function, cruise down the highway at approx 55 mph. While maintaining steady pressure on the accellerator, use your left foot and squeeze the brake enought to light the brake lights. You will hear the rpm climb approx 2-300rpm. When you release the brake, rpm will drop again. I usually do this 2 or 3 times to hear it work and continue down the road. Not a bad idea to check it once a month or so. Quick, easy, free, and no grease under the fingernails
They allow for better gas milage, sometimes 3 or 4 mpg
They allow rpms to drop 2-300 rpm
Temps in the trans drop like a stone.
The ecm looks for a few things, then it commands lock up. The pressure switches in the valve body look for the pressures required and normally complete the circuit. This allows for the lock up solenoid to activate, opening a mechanical valve in the pump. This valve permits fluid to the converter to lock up the large plate inside. It then allows for the converter to go 1:1. Zero slippage internally allows for the good things I listed at the top of this page.
Failures in the lock up circuit should be corrected asap. Repairs are typically very inexpensive.
To test for proper lock up function, cruise down the highway at approx 55 mph. While maintaining steady pressure on the accellerator, use your left foot and squeeze the brake enought to light the brake lights. You will hear the rpm climb approx 2-300rpm. When you release the brake, rpm will drop again. I usually do this 2 or 3 times to hear it work and continue down the road. Not a bad idea to check it once a month or so. Quick, easy, free, and no grease under the fingernails
