Ask Hagerty Concierge Service a Big Hit


The “Ask Hagerty” Concierge Service was started to help customers get answers to questions on anything collector-car related. If we don’t know the answer, we’ll help find it for you. Here are a few questions recently asked.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2006/10/05/ask-hagerty-concierge-service-a-big-hit


+Can a 4.11 crown and pinion gear be replace by a 3.51 ratio crown and pinion gear on a 1985 Ford
F150, 351 ci. 4bb high output,and if so do I need to change the axils.
Desperate to know.
Best regards


Hello @bagrieg -

Good question you’ve got on the F150 rear end. Based on the information you provided it should be a Ford 9", which is an axle that has lots of aftermarket support. The ring and pinion gear can be changed, and should not require new axles. Many performance part venders carry Ford 9" ring an pinion gears in various ratios.

There will be coding on the axle that can tell you more about he internals of the axle also, including the current gear ration and number of axle splines.


Hello Kyle;
From where does the wire come from that attaches to the automatic
choke on a 351 ci V8
4bb on a 1985 Ford F150 ?
Thank You


@bagrieg - After some research, it appears the factory drew power for the electric choke from the stator terminal on the alternator. I would recommend purchasing a factory service manual to check the wiring diagram and ensure it is connected properly.