First year for TCC Lock-Up

Anybody know what year the Caprice introduced the lock up clutch on the transmission?

EPA fuel economy (if you believe it) jumps from 16/24 MPG 1986-1988, up from 15/21 MPG in 1985, so I"m guessing 1986 was the first year?

Thanks

Nope, first year was 1979 - the TH200C and TH350C were lockups.

Didn't know that. Thanks. So what kind of 'smarts' did the car use to lock-up the TCC?

I don't think Throttle Position sensors came till the mid 1980s and the first computer was 1981 if I recall. Just curious how the transmission would know when to lock-up and when to disengage.

Thanks

Again, 1979 was the first year for computers in GM cars. Not all cars had them - and they were somewhat rudimetary next to the C3 system introduced in 1980. Thottle position sensors were available with starting with the first units.

The TCC has always been controlled with the computer.

Not true, the very first TCC was controlled with a series of elaborate set vacuum hoses and diaphrams which measured the amount of vacuum, when it leveled off and stayed there for 30 secs or so it locked the TCC. When the Vac. raised or lowered it would kick it off. Also the brake light switch was wired into this system. BTW info came from GM service manuals for th350, th400, th2004r, and th700r4.

Not true, the very first TCC was controlled with a series of elaborate set vacuum hoses and diaphrams which measured the amount of vacuum, when it leveled off and stayed there for 30 secs or so it locked the TCC. When the Vac. raised or lowered it would kick it off. Also the brake light switch was wired into this system. BTW info came from GM service manuals for th350, th400, th2004r, and th700r4.


78 in some of the buicks
called the C4 system early on

then 79 it was optional in a few more makes and models and then in 80 up it was pretty much on all light GVRW vehicles, cars, pickups under about 8200 GVRW

heavier trucks had just TCS stuff(control relay mounted on top of valve cover and an electric switch in the tranny) but no EST/ESC/CCC

good luck