transmission mystery
 

At cooler temps in Austin and San Antonio my transmission in the 1987 420sel that I love will actually slip into reverse. When the operating temperature rises to 80C then there is no such hope of sliding into reverse.

Now I believe that transmissions don't necessariy like new fluid and this has happened for the past year or so. When I first traded for the vehicle, I would slide into reverse after a minute or so on a cold morning, but as the temp warmed up, no chance....

I changed the fluid and added a Lucas Transmission Oil thickener thinking that doing so might help the issue....no such luck...now december and I am back to sliding into reverse early in the morning but that is it....

Ideas anyone?

Lyle in Austin

Count on reverse being Gone in the near future..it's only working when the fluid is cold & thick..

Have you adjusted the modulator pressure? If not I'd give it a few turns see if that helps w/ reverse engaging.

I'd also try swapping the fluid w/ Type F if you are on a budget or B&M trick shift if 5$ a qt is OK... Both of these fluids additive package is aimed at getting clutches to Grab as opposed to slip.

Jonathan