Torque converter lockup speed.
Thread Starter
7th Gear
Joined: Sep 2004
Posts: 7
Likes: 0
Torque converter lockup speed.
A couple of years ago I had some transmission work done on my 80 L48 automatic. Prior to the work the torque converter locked up around 30 mph (50 K). Afterwards it locks up around 50 mph (80K). My question ... Is there an easy way for me to adjust this back to 30 and if so ... what might be required?
Thanks for any assistance. I've been reading but can't find the answer so far. F.
Thanks for any assistance. I've been reading but can't find the answer so far. F.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Lockup is controlled a couple of ways. A 350C has a vacuum switch, a pressure switch, and the brake light switch. A 700 can have the same or more. Did the shop change the valve body? they may not have changed the pressure switch over from the old one. There are several different switches, it's just finding the right one. They used to be available with the pressure rating stamped in the body that was almost the same as the road speed. If the switch was stamped 35 it would come on about 35 mph. drop the pan and see what's in there and then find a pressure switch that's about the right number- easy to test too. Rig a fitting on an air tank and a meter.
