The Stovebolt Site Forums The Parking Lot Big Bolts new third member for rear axle

Guys ive been trying to come up with a solution for my busted 2 speed rearend. Ive thought of replacing it with a dana 80 from a p30 van. I'm also thinking of just swapping the third member out two a single speed. I'd like to here your opinions. Also i'd like to verify that the single speed with fit right into my 2 speed rear housing and match my axles. I have found a single speed diff but it is going to cost me 600 including shipping. I'd hat to get it and find out that it doesnt fit or that I also have to swap axles
or anything else. The numbers on my rearend now are:
3711468
GL109
Can you confirm that these numbers are a 15000lb axle?
From my searching I have found that the 2 speed axle is called a gm t-150
and the single speed is called an h-150. This is for the 15000lb axle.

What year/series is your truck?

Can you confirm the "G" is really a G and not a C.

Also, what are the numbers on the single speed rear?

Mike B

Mike yes it is C. I dont have the numbers on the single speed. I will see if I can get them tomorrow. My truck is a 59 gmc 350.

If you could use another 2 speed, I have one from a 1965 GMC 4000 grain that has low miles on it.

If that is an offer for sale or for free please either use a PM or the appropriate section of the Swap Meet.

Thanks,
Grigg

bcgmc,

I can't find the 3711468 casting number in my Chevrolet books (didn't realize you had a GMC until just now)...maybe it's a GMC number?

I do find a GM 15,000 pound 2-speed rear with the code "CL" as being made from 1955-59, it's has 6.40/8.72 gears.

CL = Code
109 = date (October 1959).

Is it Vacuum or Electric Shift?

Why are you looking to swap to a single speed rear? The 15k GM/Chevrolet single speed rears had 6.17 or 7.20 ratio. I don't think you will see enough gain to make it worth the effort/money to swap from 6.40 to 6.17...(3.6% increase at 55 mph = +2 mph more).

Whats the ratio on the rear your looking to buy?

Mike B