Toronado.org

I love my car, and I like to cruise around town at 25 or 30 MPH. My car doesn't want to shift into third until 35 or 40. Running through town in second seems like I'm screaming for attention.


I'm having the fluid and filter changed today, and I remember the TH400 in my GTO shifting very firm, but not late.

Is this normal?

My first thought is that the two small vacuum lines from the carb that lead to the vacuum advance and transmission are reversed. Remember that on the carb, one line is ported and the other is constant so swap the lines on the carb and see if that makes a difference. Also, I believe the vacuum modulator on the transmission is adjustable. Just follow the vacuum line from the carb to the trans, pop off the line at the modulator and you'll see a very tiny flat head screw inside the modulator. Give it one full turn and see if that changes your shift points.

Chris

Hi, just had a new modulator installed on my 66........He said it is normal to shift into 3rd at around 35 to 40

oltoronut wrote:Hi, just had a new modulator installed on my 66........He said it is normal to shift into 3rd at around 35 to 40

Thats what I wanted to hear. It feels good and shifts firmly, but it just seems to stay in 2d for a long time.

Hi again I also found the passing gear switch in the wrong position. It has no linckage hooked up to it and the trans thought we wanted passing gear...; Makes for weard shifting.
Make sure your switch is in the right position. Or hooked up to the carb.

The fluid and filter change helped my 1966 425/425 at first.

Then it really didn't want to shift out of first.

I examined the lines, and found a cracked T fitting in the vacuum line between the carb and transmission.

New fluid and filter, and ensuring a leak free vacuum plumbing and now it shifts clean, firm, and exactly when I think it should.

Thanks for the advice from everyone, I hope this helps someone else.