1939 ford gear ratio 3.78 or 3.54

[Talkwrench]

This has been on my mind. I will have to sort out what gearing I have.. Suspect it would be 4.1 as its a pickup. I'm running 6.50 x16 on th rear. I do get worried about over gearing it as they are not a very powerful motor yet I should be happy it pulls from next to nothing and will still happily sit on 60 mph..

[G.M.]

I put 125,000 miles on my 39 convertible with a 3:78, Columbia 28% overdrive with 600/16 tires. I have had very few times I had to down shift even in hilly country. I visited Walt up in Maine years ago but don't remember if I had the 39 convertible or the 39 P/U. Both have the same rear set up. I don't go into a hill at a slow speed and expect the speed to pick up going up a large hill. When I see a hill coming up I speed up going into the hill and have had very few times I had to down shift except on mountains. I have some 6 blade industrial fans on several of my cars with the generator mounted fans which don't make much noise. I don't hear any fan noise on the crank mounted fans. G.M.

[Ernie]

Walt... Can i call you ?
Ernie

[41panelmark]

Originally Posted by Walt Dupont--Me.

With a 221 stock engine, if you live in hilly country, you'll always gearing down on hills with 3:54, but if you do alot of turnpike cruising 3:54 is the way to go. Walt

That is about it, I have 3:54's love them on the highway flat out but you do shift a lot more going up to the high country. Glad I swapped them out with the 4:11's.