trans ratio

[claybill]

are the transmissions of the 40's...all the same ratio? and even into the 50's?

different trans ratios would cause match up difficulties with different rear ends....anybody have any specifics. i have heard that G>A> has adapted some trannys with a special second gear? whatever that means.. any help or discussion..

and about the rear end ratio....can you pop a 1950 3.7 rear gear into a 1946 housing....? will they all bolt up , 40 thru 56 or so. opinions?

bill

[greg g]

apparently there was a 2nd gear ratio that was taller (numerically lower) then others, which give a higher speed. I know mine with the 4.11 rear is pretty much done at 40. I believe the other ratio is good to about 55 or so. Third is 1 to 1 as was the prevelent practice. I think Tim A posted the gear ratios a while back, search his posts.

Can't comment 100% regarding the rear gears. But I believe they are swapable.

[grey beard]

Except for overdrive units, all high gears were 1:1 - meaning one turn in equals one turn out. Lower gears varied, especuially with trucks, where several transmission types were used.

Hope this helps.

[Young Ed]

Bill 50-47 works. In either 53or54 the spline count changed on the axles and you have a little more work to do then. Dad and I changed the spider gears from my 4.10 into the 3.73.

[Plymouthy Adams]

this I posteed for another reader:

going by the Plymouth book for the three speed...

2.57 first

1.83 second

1.00 third

fast second is 1.55

[47dodgepu211]

I'm sure my stock 47 WC half ton has the 2.57 1st and 1.83 second. I live in Montana. Who knows of some place in Spokane, WA that could replace 2nd with a fast second. I haven't found anyone here in Montana that can do it but I'm still looking. Cost is a factor as well otherwise I would consider some kind of rear end swap to get better brakes.

John

[Jim Yergin]

My understanding is that the "fast second" gear was used up to 1940 with a change in 1941.

Jim Yergin

[Paul Hoffmeyer]

John, the pickup transmission and its ratios are entirely different than the car trannies. I counted the turns on the one from my '45 WC and came up with 3.4 for first and 1.8 for second, with reverse coming in at approximately 4 to 1.

Paul H

[randroid]

Gents,

And all this time I've thought the reason for a tall second gear was to make up for not putting a synchro in first. I'll be deep-dipped!

-Randy

[47dodgepu211]

Thanks, Paul H. Yes, my 1st is only good for 10 mph and I rarely start in 1st. 2nd is good for about 35 mph. Top speed is about 60 mph really wound up. so making the change to a fast 2nd might not be good for me.

John