Does drive shaft need to be balanced after installing U-joints?

[MarcDeSoto]

I'm planning on installing new U-joints on my 48 DeSoto myself using the vise and socket method.  Do I need to have a drive shaft shop balance my drive shaft after installing the new U-joints?  

Edited October 16, 2021 by MarcDeSoto

[Dodgeb4ya]

Not if you install them properly ...the only way.

[Bryan]

On my 92 Dakota truck they took it off to straighten and balance it.  That was after I checked runout with a jack, chalk and dial gauge and thought it was too much.   They spot heat and cool it to straighten it..   Didn't cost much.

[Bryan]

There are great Youtube videos on how to do it right.   Whether the Ujoint gets off center depends on the type.  Some with the grooves can't, other types can. One thing is don't warp the holder ends while beating the joint out..check across the holders with a parallel bar. Also wrap around the joint with tape when you get the new one together to keeps the caps from falling off..the needle bearings would be a pain to get back in.

[MarcDeSoto]

Since the U-joints for 1940s MoPars are rare, maybe I should check my current U-joints to see if they even need replacing.  Maybe all I should do is clean and lube the caps?  

 

[Dodgeb4ya]

You have those DeSoto only "Batwing" joints as you know.

Tough to find.

I think I sold you one of those.

[Bryan]

3 hours ago, MarcDeSoto said:

Since the U-joints for 1940s MoPars are rare, maybe I should check my current U-joints to see if they even need replacing.  Maybe all I should do is clean and lube the caps?  

 

That's a good idea. You can run into real problems with stuff that's supposed to be a 1 hr job. I had to grind the end off of one old joint to get it out.  

 

[MarcDeSoto]

I checked my old u-joints and they are tight as a drum.  No play at all.  Maybe I'll clean and re-grease the caps and install.  Dodgeb4ya, you sold me some impossible to find C-clamps required for my 48 DeSoto.  Then a month later I found my original C-clamps, bolts and all!  But thanks for selling them to me.  

 

Edited October 16, 2021 by MarcDeSoto

[Dodgeb4ya]

That's right Marc...

The U-joint cap retaining clips!

It's DeSoto week around here...I just got two M5 DeSoto transmissions.

They are M5 because the model code is stamped on them and they have the required odd DeSoto U-joint flange on the E-brake drum.

[MarcDeSoto]

Wouldn't DeSoto and Chrysler 6 have the same U-joint flange?  

[MarcDeSoto]

When you clean U-joint caps, should you remove all of the needle bearings and clean off all the grease, or leave them in place and just re-lube them and install?  

[Dodgeb4ya]

3 hours ago, MarcDeSoto said:

Wouldn't DeSoto and Chrysler 6 have the same U-joint flange?  

No....different designed shaped wing caps.

[chrysler1941]

My friend's 49 DeSoto also uses Mechanic style u-joints, but they differ form mine as these do not have bolt holes, but rather retaining brackets. Don't know if it's a DeSoto thing or a pre-post war thing.

 

According to professor Kelly, pressing a u-joint on caps will destroy bearings

 

 

 

Edited October 17, 2021 by chrysler1941

[Bryan]

Dang...come work on my car.  If they looked normal from the outside (not a lot of corrosion and dirt) and have no play like you said I would leave them alone.  Go riding instead and enjoy. Maybe check the rear axle bearings by jacking it up and trying to move the wheel  up and down.  (That's how I ended up with mission creep and overhauling the rear end on my 92 Dakota).   

[Dan Hiebert]

On 10/16/2021 at 1:19 AM, MarcDeSoto said:

I'm planning on installing new U-joints on my 48 DeSoto myself using the vise and socket method.  Do I need to have a drive shaft shop balance my drive shaft after installing the new U-joints?  

Short answer is no.  

 

4 hours ago, MarcDeSoto said:

When you clean U-joint caps, should you remove all of the needle bearings and clean off all the grease, or leave them in place and just re-lube them and install?  

You wrote that your u-joints are tight.  Ensure they operate smoothly.  If so, you may want to reconsider messing with them at all just yet.  You certainly don't need to replace them.  I don't believe these u-joints were originally intended to be serviced, just replaced if the car lasted long enough.  Our cars also weren't intended to be on the road more than 10 years or so either.  That being said, grease breaks down.  You've already had/got the car apart, if you do decide to disassemble the u-joints, then the caps and needle bearings should be thoroughly cleaned, which can be accomplished without taking the needle bearings out, but you have to be careful, and don't use compressed air or you'll be hunting for those bearings all over your garage.  When you re-grease something like that, you should always thoroughly clean out all the old grease to ensure longest life from the new grease.  If you don't think you cleaned them enough, you can remove the needle bearings easily enough to clean them, just be careful about it.  They aren't that hard to re-install, just a bit tedious. 

[chrysler1941]

20 minutes ago, Dan Hiebert said:

When you re-grease something like tha

Read somewhere not all grease types will do. Isn't there a special grease for this?

[Dan Hiebert]

On 10/17/2021 at 8:40 AM, chrysler1941 said:

Read somewhere not all grease types will do. Isn't there a special grease for this?

I haven't researched this very much, others may have.  As long as the seals are air/moisture tight, modern multi-purpose bearing grease will last a really long time.  Probably longer than most of us will need to worry about.  I've pulled 50 year old stuff apart that still had serviceable grease, and 10 year old stuff with bad grease.  Semi-surprisingly, there were still some parts with probably 80+ year old grease in them on our Terraplane...none of that was any good.  1937 seals were seals in name only.  The difference seemed to be contamination.  In a nutshell, if it smells bad ("rotten" grease is rank, certainly doesn't smell like grease any more), it is.  But the only way to tell is by taking whatever you're working on apart.  Modern grease is simply engineered better by virtue of continual improvement of the product.  Peace-of-mind after having refurbished appropriate parts with fresh grease will go a long way.   

Edited October 24, 2021 by Dan Hiebert