Differential Questions

[Don Jordan]

My differential is leaking so I was going to replace the seal.

Questions: is there a trick to get the old seal off?

I don't want to break anything but for some reason I can't seem to get the drive shaft off at the transmission. It seems so silly since I've changed the U joints on my other car in the past but I"m having no luck now.

Last question: is there any difference between the leather U joint covers and the rubber ones? I believe I got leather ones from Bernbaum. My 48 has rubber - 47 leather. Just checking before I order new ones.

Thanks,

[P15-D24]

Easiest way I have found is use a slide hammer with claws to pop it out after getting the diff hub out.

 

For the boots either will work fine. The rubber ones are a bear to get over installed pin on the u-joint. 

[Don Jordan]

I gotta tell you my hat is off to the Plymouth motor car. Wow. I got the drive shaft off (a few taps with a hammer). I took off one of the rubber covers and in the gunk around the U joints was a bearing. The car has been running without any vibration, noise, signs of something wrong. I have no idea how long it's been like that or how long it would have lasted. But it did last and did not let me down. Of course now I have to find new U joints. What a wonderful car. I haven't checked out the front bearings yet.

I don't have a slide hammer - I do have a wheel puller though I don't know where to connect it. The service manual shows a special tool. This is tomorrow's chore.

[TodFitch]

No noise, vibration or signs of anything wrong? Is there play in the universals?

 

They should be able to slide in and out but there should be no rotational play and if you feel the inside of the housing where the ball runs it should be straight and smooth.

 

If so then you might be able to just clean the old lube out and repack them with no need to buy a replacement set.

[Merle Coggins]

Drill a couple of small holes through the metal flange of the seal, just inside the outer diameter, one on each side. Screw in sheet metal screws, then grip the heads of the screws with Vice Grips. You can either pry against the Vice Grips or tap on them with a hammer to pull the seal out.

 

Merle

[desoto1939]

Are you tryin to pull the pinion seal or the differentail gasket?

 

You will need puller if you are trying to get the pinion seal out and also a seal driver to get the seal back in.  I have the millers tools to get the pinion flange off the diff and the tool to pull the seal and the drfit to install the seal and the toolto install the pinion flange.  These are all factory Miller Tools.

 

ALso have detroint Pinion and Trunion U joints with the body and Internals also with leather and rubber boots.

 

Rich HArtung

Desoto1939@aol.com

[Don Jordan]

Tod: you are correct - I could just repack the needle bearings and go on my way.  But since I've got them all apart I might as well put in new and feel secure they will last.

 

Looking in the parts book the offending seal is 3-22-45.  But I can't figure out how to get it out.  I will take a picture of it - that might help.

 

Rick I will e-mail you and we can discuss the U joints.  I see they have them at Bernbaum's but I'd like to keep it in the "family".

[Don Jordan]

I am truly in need of help. Both mental and physical. I did a search trying to find how to get the differential seal off and I read about using an impact gun. I've looked in the parts manual and see a nut. But I can't find it. What am I missing here?

[Dodgeb4ya]

Never seen that before on an old MoPar! Must be an after market cover plug?

Should look like this...

[Don Coatney]

You might just leave well enough alone. How bad is your seal leaking? Is it pouring out or an occasional drip? As you have a lift you might simply pull the car on the lift every thousand miles or so and top off the differential oil.

[plyroadking]

Looks to me like the spring cover off the u joint. It is supposed to be attached to the end of the driveshaft. Should be one on both ends, i assume you can just pry it out of the flange to access the castle nut

[Dodgeb4ya]

If not leaking too bad Like Don says I'd leave it alone. Otherwise you probably will have to punch a hole in it to pry it out. I think it was a after market pinion nut anti-leak cover? I have seen that style cover on some import car rear axle hubs.

Bob

[TodFitch]

Looks to me like the spring cover off the u joint. It is supposed to be attached to the end of the driveshaft. Should be one on both ends, i assume you can just pry it out of the flange to access the castle nut

 

 

Agree that it looks like a cover for the universal joint. Supposed to be tabs that hold that onto the joint and that cover holds the centering spring in.

[Don Jordan]

I pried at it and got the plate off. I could just let it leak but it makes a mess. It would be just my luck that I would go on a trip, be in the middle of nowhere and have it seize up. I got into old cars so I could play with them. Just ignoring a problem doesn't make it better. I'm sure it's going to be a hassle but what else do I have to do? Who knows I may even learn something. I still appreciate all your help and comments - thanks.

[Dodgeb4ya]

DUH!!!!!!

Makes a nice cap though!

Edited May 31, 2013 by Dodgeb4ya

[Don Jordan]

I don't know if anyone is still following this thread but I have an observation. I got the drive shaft off. Pulled the piece off the differential. (I don't have my parts book handy so I don't know the name). I took out the offending oil seal but when I looked closely at the shaft it had kind of a red hue to it. Almost like transmission fluid. Is this normal? I drained the differential and all the oil that came out seemed clear. I tried to take a picture but the color didn't show up. I know I'm probably paranoid but since I'm this far into it I need to be assured everything is alright. I just found it interesting.

[Jerry Roberts]

Part of this job is to make sure that the air vent on top of the differential isn't plugged up . And be sure to put a little grease on the lip of the new seal so that it doesn't operate dry on the first revolutions . 

[Don Jordan]

OMG! I don't think I've seen an air vent on the top of the differential. It's got 60 years of crud on it. I plan on taking a wire brush to it. Is this a joke?

[Young Ed]

Not at all. Look where the flex line Ts off into the steel lines that run on the axle. That  should be held on with a special bolt that is also the vent.

OMG! I don't think I've seen an air vent on the top of the differential. It's got 60 years of crud on it. I plan on taking a wire brush to it. Is this a joke?

[mmarkovich1]

Hi, I am new to the web site. I have 1950 Plymouth Special Deluxe. Looking for expert advise. Leaking differential. Three attempts to stop leak with new pinion seals. Last replacement this weekend. New seal (National 7216, new speedi sleeve to cover worn groove in flange shaft, new 90 weight GL4 and GL5 fluid. 

 

Still leaking and I didn't even test drive it yet. 

 

I can't just let it leak. The under carriage has been cleaned and detailed. I don't want fluid all over the underside of the car. 

 

Any advise would be GREATLY appreciate. I hate leaks!!!

 

Thanks if you advise,

Mike

[Plymouthy Adams]

how tight was the seal on the shaft prior to install?  next...is the leak about the shaft/seal or at the housing/seal where it may have suffered damage from an earlier removal by a PO..

[mmarkovich1]

New seal - National 7216 leather. seal on the shaft tight. Need speed sleeve on the shaft. 

 

Leak is shaft/seal and running down the bottom of the differential and dripping on the ground.

 

There is a gap between the shaft face plate and front of the differential/seal face. Any chance the shaft is not far enough into the new seal? How can I push the shaft in further? I tighten the nut down with an electric impact wrench but forgot to mark everything before I disassembled for the new seal replacement.

[Plymouthy Adams]

am now confused by your two conflicting post...Post 20 states new speedy sleeve..post 22 states you need speedy sleeve...unlike the later carriers that depend upon a crush sleeve for pinion back set and bearing presets..the use of a spacer and shims is used in these.  You should only have to ensure the work is clean and that the nut when put back on is torqued between 180 and 320 ft lb..do you have the book for your car...this is well outlined there and will also give you the benefit of an exploded view so you can understand the why of what you are doing..

[mmarkovich1]

Typing error on my part. I do not need a speed sleeve. Should have said NEW speed sleeve. I have a manual and followed directions. 

[busycoupe]

Was the leather seal soaked in light oil or kerosene to lube and swell it before installation? Was it at least greased a little so that the shaft was not turning on a dry seal? If the seal was installed dry it may swell and slow your leak as the differential oil soaks into it.

Dave