Packard Forum Index » V-8 (1955-56)

Thanks, is it difficult to adjust the throttle linkage? It was set up for the '55, top hole, and I had my mechanic reset it to the middle hole, per the service manual, and adjust the throttle linkage. That made a difference in the shift pattern and I'm wondering if that adjustment needs to be done again to fix the tranny from not shifting out of first in D?

I don't believe there is any differecne in throttle linkage adjustment between the manual (lever) and push button selectors.

However, it is important to review ALL of the supplemental bulletins and articles pertaining to this linkage adjustment because the procedure was revised more than once. I also seem to recall the factory reported an error in the shop manual or training booklet. Again, you'll find these topics neatly reference in this website's Service Index.

Adjusting the throttle linkage is not that difficult, but a bit tedious. Also, you have to hold the linkage in such a way as to prevent stressing the joint at the carb; otherwise it could break.

Now, think of the automatic transmission as being controlled by a hydraulic computer. In general, the transmission senses: 1) engine speed, via front pump pressure: 2) vehicle speed, via governor pressure; and 3) driver demand, via throttle valve pressure. Thus, in determining what "gear" to use, the transmission considers driver demand and compares engine speed to vehicle speed. This is a bit of an over-simplification, but it should tell you that throttle linkage adjustment is critical.

Yet, while throttle valve pressure determines the point at which a shift occurs, I cannot say for certain that it would prevent a shift from low to high.

Again, be sure to review the bulletin on adjusting the acutator and checking the control valve position. That work is a bit more involved than adjusting the linkage, but I could accomplish it at home with the car properly perched on reliable set of jackstands over a concrete floor.

When I brought it back the first time after the rebuild for leaking, it was not fixed nor was it free, though we did negotiate the charge down.

Thanks, Ill take a look at the bulletin to see if that can help me this weekend when I have some time to look at it.

Gene