Question about a 1948 Dodge Rear end

[xxwelderxx]

Did the 48 Dodge come with a 3.73 rear end?? If they did could the 3rd member interchange with a rear axle in a 53 Plymouth??

[Merle Coggins]

3rd Member is another name for the differential, diff, hogs head, rear end, etc.

As for the interchange, I remember someone (think it was Ed) mention a axle spline change that happened somewhere in the early 50's.

Merle

[Young Ed]

Twas me. Learned that lesson the hard way. Got the diff all installed and the axles just went thud against it. Ended up swapping the diff gears into my old housing. You can do it that way or swap the side gears. We did mine that way because the bearings turned out to be bad in the 3.73.

[Normspeed]

I know that by 53 the axles had more splines. Hollander book tells the whole story but mine is at home and I'm not.

[55 Fargo]

Ed, do you know if I can swap the hoghead from a 1948 to a 1951, I have a 3.54 here and would like to install the innards to the 1951 4.10 I have in my 48 Chrashler...........Thanx Fred

[55 Fargo]

Norm, when yopu have time could you check your Hollander book for me......Fred

[Young Ed]

48-51 should be good to go. No need to just install the innards. Swap the whole diff carrier as an assembly. Check the thread length on your studs in the axle housing. For some reason the diff carrier in my truck was thicker in spots so I ran out of threads on a couple. No big deal if you are prepared.

[xxwelderxx]

Well then, I guess i will just have to switch out the gears into my present 3rd member.

Am I looking at a clean swap of gears??

[Young Ed]

Right. I have a 3.73 in my original 4.10 housing in my 48. Gets you decent speed for the highway.

[Normspeed]

Sometimes Hollander books can be hard to decipher. The Plymouth and Dodge rear ends were pretty simple. The axle splines changed in 53. they went from a 10 spline to a 16 spline axle/rear end.

Chrysler is a lot harder to read, there were lots more models and variations listed. I ended up confused and my eyes said "no more".

Norm, when yopu have time could you check your Hollander book for me......Fred

[55 Fargo]

Thanx Ed and Norm, by the way how much play should you have when you grab a hold of the driveshaft and work it back and forth, is there a rule of thumb fo this., does this look like a typical diff from 1940 to 1950, as I am not 100% sure of it's origin, it supposedly is from a 1951 Dodge where my engine and trans are from:D .........Fred

[55 Fargo]

Okay, what and how do make the switch, is there anyway I can tell beforehand if the partscar diff is anygood. What parts, gaskets, etc do I need. The brakes can stay on I would imagine. Should I take the parts car hoghead to a shop and have a pinionseal installed and have the backlash set.....Thanx Fred

[Young Ed]

Fred

You will need a system to pull the rear drums and then the axles. Pulling the drums has been covered a bunch in other threads. Then you can unbolt the backing plates and move them out of the way. Not sure you'll be able to get the brakes far enough out of the way without unhooking the steel lines. Then you can put something between the drum and the axle housing and use the axle nut to pull the axles out. Someone mentioned wood we have a piece of PVC just for this. Just be careful not to get too tight that the drum gets stuck back on the axle or its back to the puller again. Keep adding washers so you don't get the nut too tight.

Once the axles are out you can pull the diff out. You will need a new gasket for the diff carrier which last time I checked was no longer available from conventional parts houses and had to be ordered from Roberts or Bernbaum. A new pinion seal is a good idea also. No reason to mess with the backlash. The new seal doesn't affect the backlash on this type of rear end. You will possibly need to adjust the shims on the axles. I believe each one should have .003 but don't quote me on that. Also might as well take a good look at your rear wheel bearings while you have them out.

[1just4don]

Along time ago I was doing some dirt work away from home. I heard the rear bearing starting to squeak and didnt want trouble so I took it to a local shop and had it fixed that day. I just didnt want anything to happen far from home. This was on an old '66 Dodge pickup with camper shell over back.

Next day I was flying low down the highway,,,and noticed my rear wheel and axle pass me on the wrong side.,,,doing about 60 per. It stayed up for a while down the highway(normal stance),,,when it slowed down it went down on the backing plate on that side and rubbed along as I came to a stop. Brakes sure didnt work then,,,so just coasted to a stop. Hopped right out to inspect damage and found heat from skidding on concrete had ignited the brake fluid and it commenced to burning. Concrete highway,hard surface shoulders,,,grass outside of that,,,NO dirt to throw on it nowhere. Got down on hands and knees and huffed and puffed and blew her out with red faced lack of breath. Got it out eventually,,looked up and right above there I had a barrel of gas15-30 gallons in it,and a 55 gallon barrel of diesel fuel plus a few assorted oil jugs!!!,,,which over time had soaked all the way thru the iron plate floor that somebody replaced the rusted out one with. I thought,,,sure glad I blew hard enough,,,that would be quite a kaboom and dont think the pu was insured for roman candle explosions.

Found out the mechanic got the wheel bearing in backward and it forced its way OUT instead of riding correctly. This is my story and I am sticking to it!!!! What a ride, thought I was taking off in a jet at the angle it dangled with NO wheel on!!! Not ALOT of steering control either.(with the nose that far in the air). DO NOT REPEAT this at YOUR house!!!

[Plymouthy Adams]

At theme parks across America people line up for blocks just to pay good money for the thrill ride you experienced.

[Young Ed]

The 66 Fury 3 we just sold for parts had been driven with the bad bearing until the wheel came out and hit the 1/4.