1948 rear axle question

[colinlesser]

does anyone know what rear axle a 48 roadmaster series 70 with the dynaflow has? or what years are interchangeable or where i can get a replacement pinion set?

[theoldguy]

1940 through 1955 interchange, but you may have to change the drive shaft and torque tube.
The 53-55 V8 dynaflow cars had better ratios for the road.

[39CENT]

I would look for a used, complete rear axle. Ive found them on craigs list etc, lotta guys taking them out for customs or hot rods. They usually just want to get them out of the way. they may have anything from a 4.11 [stick shift] to 3.43 I think, anyway you want to get around a 3.61 or higher.

[JR9162]

1940 through 1955 interchange, but you may have to change the drive shaft and torque tube.
The 53-55 V8 dynaflow cars had better ratios for the road.

What ratios did they have?

[theoldguy]

The V8 dynaflow cars have 3,4-3.6 axle ratios. I have a 55 century rear axle in my 40 with the 3.4,and it makes a real road car out of it.

[49roadie]

My 49 roadmaster had a 4:11 and I put a 52 Roadmaster rearend into it perfect fit other than parking brake cable bracket that needed to holes drill.d easy fix. and that 52 rearend has a 3:61 and is nice at hgw. driving.