tranny modulator
#1
tranny modulator
I have a 91 chevy sportside with a 350 engine. the tranny is a 5 speed w/OD automatic. I don't know what type exactly. I want to know what does the transmission modulator do and how do you know its time to replace.

#3
As I recall, this is a 700R4 transmission, which is a 4 speed overdrive. It doesn't use a modulator. There is no 5 speed automatic in this vintage truck 
The TV (throttle valve) cable adjustment is critical for good shifting. If it's off, the transmission becomes lunch in a heartbeat.
See the links/posts in my signature file for some information on adjustments.
Only a THM400 would use a modulator, and that is not the transmission in your truck.

The TV (throttle valve) cable adjustment is critical for good shifting. If it's off, the transmission becomes lunch in a heartbeat.
See the links/posts in my signature file for some information on adjustments.
Only a THM400 would use a modulator, and that is not the transmission in your truck.
Last edited by Joe_F; 04-20-02 at 05:03 PM.