35,36, rearend(what's the difference?)

kecouch

Junior Member
Hi guys, I am trying to find out what differences there are in a 35 to a 36 ford rear end? how do you tell the difference and are the gear ratio different? Thanks for any help.

Kent, Oregon
 
Kent-

"35 and '36 axles are the same. As for axle identification, look on the center rib of the rear axle housing and you will see a couple of numbers. A quick division of the two numbers and you will have the the ratio. However, it is unusual but, on rare occasions the rear axle inners may have been changed which altered the rear axle ratio but the rib numbers were not changed reflecting the swap. So, it is a good idea to double check everything. The standard ratio of the '37-'40 axle assemblies was 3.78 (except 60 HP). The '35-'36 was 4.11. Other ratios were available for special requests.

You will have no problem if you want to swap an entire '37-'40 rear axle assembly into a '35-'36. However, the mechanical brake hardware and some brake drums will be incompatible with the backing plates of different years.

Tom
 
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not sure,

i thought the 37 axle housing connected to the rad rods were closer to the drum on the 37. On the 35, the connection was inward torward the center a few inches. springs are the same, torque tube the same for 37 and 35. i also thought the 40 had a different length tube and spline, ect...someone posted this info a while back. OH, i found it,....try this http://www.flatheadv8.org/fordrear.htm good luck CP
 
There is a difference in the radius rods between 35/36 & 37/41. They attach to the axle bells just outboard of the middle of the bell on 35/36. The radius rods also act as spring hangers on them. On the later ones through 48 the spring hangers are forgings at the end of the axle bells at the backing plate flange. There are several variances in spring hangers even between 37 & 41. The Hot Rod Works has a picture comparison on there web site of the differences. Older axles had the 10-spline pinion and different spider gear/axle gear tooth counts than the later 6-spline types so you have to know which axles you have to keep the correct tooth count. As far as I know, parts are available for most types. Most ring and pinion sets are six spline now days but you can use them with early axle/spider gear combos or later axle/spider gear combos. In 1942 the axles and axle bells grew an inch + or - and this width was used through 48. You can still use the center section banjo and gear parts as long as you match the tooth counts on the spiders to the axles you mate them with.

Kerby
 
CP-

You are correct about the different rad rod attachments. However, I was referring to the ENTIRE assembly being used. When the entire assembly is used as a unit the shock holes, wheel base and spring locations do not change. Just slide out the old and slide under the new. If you are converting to hydraulic brakes the use of '39-'40 rear axle assemblies in place of previous mechanical brake configurations saves a lot "re-engineering" time. That is exactly what I did on my '35.

Tom
 
I installed a 37 RE complete into a 36.I did have to modify a few things , i used the 36 backing plates,had to grind slightly the tops of the brake levers to clear the axel tubes.Used the brake rods from the 36. Drilled the hole for the rod bracket in the 37 as 37 is cable oper. [no hole]. Went from 4.11 to 3.78.I think that was all i did. ken ct.
 
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