Indentify Rear Axle ratio on B-4-GA

[natetron9]

Recently purchased a 1953 Dodge B-4-GA. so it's a pilot house dump 1.5 ton truck with a 2 speed rear end. Flat head runs great but trying to get the trucks speed up. The goal is to replace the flathead with a diesel but I need to do some math on what transmission to use. Hoping someone can help me with rear axle ratio as a place to start. Secondly, has anyone looked to swap the rear axle on one of these trucks? The dump body will get replaced with a flatbed and all of the hydraulic components removed. I don't need a 2 speed rear end. It seems I can't find much info. on the 1.5 ton trucks. It is a really cool rig.

 

Thanks in advance,

 

Nate-

 

 

[Dodgeb4ya]

Buy a dodge cummins chassis drop the drive train in the GA truck.

I like em slow and stock though.

Edited January 23, 2016 by Dodgeb4ya

[natetron9]

I know the Cummins 5.9 is an option, couple things with that. I own a Caterpillar Marine engine repair shop, sooooo, my preference would be to put a CAT in it. Secondly, I still want to do the math to make sure going through all of the effort and expense will get us the performance we are after. Still hoping to find out the rear axle ratio/s being a 2 speed rear end

[wallytoo]

nate,

 

your rear axle is an eaton 1350 series.  normal ratio was 5.83/8.11.  optional ratios were 5.14/7.15 or 6.33/8.81.

 

the ratio is supposed to be stamped on the top, next to the "peep hole plug" just behind the yoke.  it'll supposedly have the higher (numerically lower) number, ie, 5.14, 5.83, or 6.33.  that would tell you what you've got.

 

wally

[wallytoo]

also, i'd be VERY interested in the 2-speed parts, other than the rear axle itself.  and the engine when you swap it out.

 

the tubing (mine is starting to rust through), the firewall shift mechanism/vibration damper, the axle vacuum diaphragm, etc.

 

PM works if you want to discuss it.  i'm in central nh.

 

wally

[natetron9]

Wally,

 

Thank you for that. Hoping to convert this thing to a diesel but the gear ratio hurts going from gas, being a higher RPM machine, to diesel, lower RPM by nature. Need to understand what I have to try and figure out how to move forward.

 

Thanks,

 

Nate-

[wallytoo]

right.  didn't figure it would be rapid.

 

the ratios are obviously pretty low, considering the small displacement and narrow torque curve of these flatheads.

 

anyway, if you get to the point where you remove the 2-speed/parts, let me know.  even if it's 3 or 4 years down the road.

 

wally

[natetron9]

Wally,

 

What do you make of this? I found these this afternoon near the "peep hole" as you suggested. The ratio doesn't jump out at me. What are your thoughts? Not sure how to insert a photo but

 

430 31

36760

 

This is stamped exactly where you said it should be

 

Thanks,

 

Nate-

[Dodgeb4ya]

As shown in the parts book...

There is also a light and heavy duty rear axle housing that's used with the Eaton 1350 two speed.

The difference is larger bearings/ spindles and axle shaft splines.

Bob

[natetron9]

Hi Bob,

 

The post above yours has the numbers from the location called out on the rear end. I would add a picture but I do not know how.

 

430 31

36760

 

Nate

[wallytoo]

Wally,

 

What do you make of this? I found these this afternoon near the "peep hole" as you suggested. The ratio doesn't jump out at me. What are your thoughts? Not sure how to insert a photo but

 

430 31

36760

 

This is stamped exactly where you said it should be

 

Thanks,

 

Nate-

 

nate,

 

 

you can email me a photo if you want:   jeeps at tds dot net

 

those numbers don't immediately jump out as being correct, as there should be only the 3 choices: 5.14, 5.83, or 6.33

 

wally

[Dodgeb4ya]

All I found were these two numbers on my 1951   2-1/2 ton JA dump..???

Someone help me too...

This truck has a factory New Process 5 speed OD .

 Should be a 5.83 or a 6.33 with the overdrive trans.

I thought on another 2 ton truck I have I found the # on the top of the diff case as shown, but also possibly stamped on the back side of the axle housing. Cannot remember.

 

[wallytoo]

appears as though the "parts manual" is incorrect.  those don't show obvious ratios.  i'll have to scrape the grime off of mine to see what's there.

[wallytoo]

so, the parts manual isn't wrong, at least for some axles.

 

here's a picture of nate's axle, which doesn't show the ratio

 

 

and here's a photo of my axle, which DOES show the ratio:

 

either bob & nate have more scraping to do, or your axles don't have the ratio stamped in them.  i don't know that bob's shows the ratio in the same place, anyway.  doesn't appear to.

 

wally

Edited March 1, 2016 by wallytoo