Jump to content

48 Chrysler axle shims and end play not making sense ???


Recommended Posts

Posted

 

I'm about to reassemble my axles on my 48 Chrysler Windsor and I'm having a mental block as to the axle end play in relationship to the shims. I have yet to see in writing or on You Tube the installation of the cone as it is being driven into the housing to seat up against the axle bearing, once the axle is inserted.

How far do you drive that cone in?

 

To me it seems like the axle end play is determined by how far in you seat that cone or race as it is sometimes referred to. The only purpose I can see the shims serving is to distance the backing plate away from the outer surface of the cone. Without the shims the cone would be tightened right up tight against the bearing once the 5 backing plate bolts are tightened when installing the backing plate.

 

So it seems to me that the shims don't have anything to do with the end play, and yet on page 27 of the service manual it mentions to add or remove shims to gain proper axle end play.  What am I missing here???

 

To me it seems by adding additional shims once the backing plate is flush or spaced just barely clear of the cone surface, will only position the outer seal a little further out, and it will allow the cone to work it's way out. Because now it is not being stopped by the backing plate. Being a tight fit, it would take a number of cornering manoeuvres to work that cone out I would think. But I suspect you get my drift. ( pun intended)

 

So my novice ( first time) way of thinking would be to drive the cone in until it is firm against the bearing,  (tapping the axle in as well so you're sure it's in as far as possible) to a point where you can still turn the axle, meaning you would have close to 0 end play. Obviously the grease will account for a little. (I'm going to use Lucas Red N Tacky grease) Then attach the factory miller tool ( if you happen to have one or fabricate something similar) and start slowly pulling the axle out,(which would in turn pull the cone out slightly) periodically checking for .003-008 end play. Or the other method would be, when driving in the cone and your about an 1/8” proud of the flat surface on the end of the housing, start checking for that end play, hammer tap on cone, check end play, hammer tap on cone, check end play, etc, etc. Until you're between .003 and .008.  Then make sure the outer edge of the cone is close to being flush with the outer surface of the shims. Add or subtract shims.  Then install the backing plate, and hu


What am I not understanding?

 

Posted (edited)

Don't tap the bearing races up against the bearing cones.

Tap the races to say a 1/16" of the axle housing end surface.

Then use the backing plate with your "balanced" side to side estimated thickness of adjustment shims installed to properly "push/set"  the bearing race to it's final installed position.

Then once both backing plsted are bolted up give each axle shaft a good wack on the axle shaft end nut....this assures the two bearing races are fully pushed up tight against each backing plate.

Then and only then can you check axle end play.

Both axle shafts at the inner  splined  ends always push/rest against the center block in the middle of the differential.

So when you wack say the left axle shaft it will force the opposite right axle shaft and bearing cone and race tight against the backing plate.

This need for using a brass or dead blow hammer to "wack" the axles is absolutely necessary to seat both bearing races TIGHT against the backing plates to get an accurate end play measurement reading.

Shims and adjoining shim mating surfaces must be clean.

Shims can be unmatched probably .020". Don't worry about them being exact...not really possible.

The bearing races rest tight against the backing plate ...not the shims.

The shims space the backing plates in or out...changing axle shaft end play by the bearing race position closer to the cones or farther away....in thousand's of an inch...

 

 

Edited by Dodgeb4ya
  • Like 1
  • Thanks 1
Posted

I always start with about 50 thousands of shims on both sides and try it and measure the movement. Then work down from there until you get the clearance you want. I use about .010 or Page31Big.jpg.3c4531fdae85d7ac39c6c683d62f96cd.jpgso to account for the higher freeway speeds and the heat that makes.

  • Like 1
  • Thanks 1
Posted (edited)

Delete

Edited by Dodgeb4ya
Posted on wrong web site!
Posted

I've been hoarding Mopar axle shims. I've picked them up here and there. I now have a decent collection of spares of various sizes! 

Only a few years ago I was wondering the same thing. Where will I get some? 

Posted

I would purchased some shim stock from McMaster-Carr and mounted it on some wood and gave it to my general machine shop. They can scanned an original and dump the data to their water jet machine. Nice new shims of various sizes. I had to do this with the '49 engine rebuild as the replacement timing gears when mounted...the lower on the crankshaft...did not line up exactly. I had to shim it out so that the chain was dead on perfect. Once could do the same with the axle shims if need be.

 

James

Posted
On 11/23/2021 at 11:58 AM, Booger said:

what to do with all those empty Busch Lite cans......?

My thought exactly.  The average beer can ( Canadian) is a bit too short.  So I'm going to pick up some taller ones and try them.  The can I tested for thickness was .005 th.   I've ended up with .004 on one side and .008 on the other side.  On the .008 side I have only one .012 shim.  So If I take that out and double up a couple beer cans I should get around .006 end play, which would be a bit better.  But since I'm within specs, ( barely) and the axles are all together now, I might make up the shims and just keep them handy.  If one of my new seals begins to leak, then I'll have the shims ready for round 2.

  • Like 1
Posted
On 11/23/2021 at 10:56 AM, James_Douglas said:

I always start with about 50 thousands of shims on both sides and try it and measure the movement. Then work down from there until you get the clearance you want. I use about .010 or Page31Big.jpg.3c4531fdae85d7ac39c6c683d62f96cd.jpgso to account for the higher freeway speeds and the heat that makes.

Page 31 of what book is that from?

Posted

I've moved on to my pinion seal and I'm curious about the end play there. I'm a little confused with the terminology here as well.  Is pinion backlash and end play the same thing?

Anyways I should have, but I forgot to take a dial reading on the pinion end play before I pulled the yoke out to replace the seal.  I read somewhere on a Forum, either here or AACA  that a guy said if you're not taking the pinion housing apart and simply replacing the seal, as long as there hasn't been any existing issues with the rear end like noise, then you'd just take a measurement of the length of the pinion shaft that protrudes past the crown nut, and when reassembling it, keep it about the same and you should be good.

I have a couple shims in behind the bearing on my car  .025 and .010.  Everything look really good.  Bearing and race looked good so I simply reassembled it as it was.  However when I now take an end play reading with a dial indicator, I have .006th.  The manual says it should be .002.  That seems awful tight, but what do I know as a newbe to this procedure. 

I guess my question is, am I ok with .006 th. end play on my pinion shaft? The problem is I might destroy that new pinion seal when I pull it to get at the shims.  That seal was monstrously expensive and I had to wait 6 weeks to get it.  Oh btw, the seal Timken sent me (#7216)was the old leather style.  Is that good or not so good compared to the rubber ones? 

Posted (edited)

Pinion backlash is the clearance between the pinion and ring gears.

 

Pinion end play is the clearance when you grab the end of the pinion and move it in and out.

Edited by Sniper
still can't spell
  • Thanks 1
Posted
12 hours ago, harmony said:

I've moved on to my pinion seal and I'm curious about the end play there. I'm a little confused with the terminology here as well.  Is pinion backlash and end play the same thing?

 

I'm definitely paying attention...

IMG_3671.JPG

  • Thanks 1
Posted
24 minutes ago, Bryan said:

I'm definitely paying attention...

IMG_3671.JPG

 

In the case of this picture, if the end play/preload is good all you need to do is replace the seal.  Since this is setup using shims and not a crush sleeve it is a simple R&R job.

 

Rockauto shows both the seal and a speedi-sleeve for this location.  SKF18880 and SKF99187.  The speedi-sleeve is designed to fix a scored or worn haft so the seal will seal, 37-54 non- 8 passenger and wagon applications.

  • Like 1
Posted
1 hour ago, Sniper said:

 

In the case of this picture, if the end play/preload is good all you need to do is replace the seal.  Since this is setup using shims and not a crush sleeve it is a simple R&R job.

 

Rockauto shows both the seal and a speedi-sleeve for this location.  SKF18880 and SKF99187.  The speedi-sleeve is designed to fix a scored or worn haft so the seal will seal, 37-54 non- 8 passenger and wagon applications.

Mine didn't look quite that messy, but similar.  I used speedi-sleeves for both my inner and outer axle seals, as well as the pinion seal.  Actually NAPA got me "Dura-sleeves"   Made in Canada eh!. Or maybe it was the cardboard box that they came in was made in Canada.  haha!

Posted
3 hours ago, Sniper said:

Pinion backlash is the clearance between the pinion and ring gears.

 

Pinion end play is the clearance when you grab the end of the pinion and move it in and out.

That's how my mind interpreted the difference, but it never hurts to ask, thanks. 

Posted
1 hour ago, James_Douglas said:

Yes of course.  I have that bookmarked but my list of bookmarks is so extensive, these days I sometimes forget to go look because it takes me forever to find what I'm looking for. 

Master Tech is awesome.  I have bookmarked every one of those videos that pertains to my car.  As well I printed out all the lessons and keep them in a binder in my shop.  

I can't seem to find that page though?  Nothing in the 1948 stuff, and it wasn't page 31 of either of the two lessons on axle adjustments for the 1949  Nothing under 1947.

I'm cautious about information on years other than 1948, since I might be learning something that doesn't pertain to my particular car, or even my model.  As an example, according to the service manual for 1948, it seems that the C38 is the only one that used the shims behind the pinion bearing.  Perhaps if I was more experienced around rear ends, I would know what information to pay attention to and what to ignore.  

Posted
2 hours ago, harmony said:

Yes of course.  I have that bookmarked but my list of bookmarks is so extensive, these days I sometimes forget to go look because it takes me forever to find what I'm looking for. 

Master Tech is awesome.  I have bookmarked every one of those videos that pertains to my car.  As well I printed out all the lessons and keep them in a binder in my shop.  

I can't seem to find that page though?  Nothing in the 1948 stuff, and it wasn't page 31 of either of the two lessons on axle adjustments for the 1949  Nothing under 1947.

I'm cautious about information on years other than 1948, since I might be learning something that doesn't pertain to my particular car, or even my model.  As an example, according to the service manual for 1948, it seems that the C38 is the only one that used the shims behind the pinion bearing.  Perhaps if I was more experienced around rear ends, I would know what information to pay attention to and what to ignore.  

I was only on page 30.  So I found that illustration with one click of the mouse to go to the next page. Sorry for not being more attentive James.

 

Posted

Another concern I have is the preload on the pinion castle nut.  According to the service manual there should be around 15 in.lb. of torgue.  My in. lb. torgue wrench is 1/4" drive and I don't have a 1/4" to 1/2" adapter.  ( probably no such animal)  so I put a 3 in. extension on my torque wrench and set it at 15 in.lb and then put the extension in the vise and give the torque wrench a pull. It's not much more than finger tight effort to get the torque wrench to click.  So I sort of tightened the nut to get any slack out.  Similar to the front wheel bearings, then found the closest opening that lined up the hole in the pinion shaft with an opening in the crown nut.

Am I close?  Is there a more high tech way of accurately tightening that pinion crown nut?

Interestingly when I took that nut off, it took a huge amount of effort to get that nut to loosen.  A 3 foot pipe slid over a 1/2" ratchet and a lot of grunting.

Posted

Don't know whether a click torque wrench will do it.   On my 1992 Dakota pinion preload had to be done with a rotational toque wrench in in/lbs.  CDI 752LDINSS Torque 3/8-Inch Drive Dial Torque Wrench - Cdi Torque Products - Amazon.com  $$ Was ouch ouch back then!  Amazon.com: Neiko 30249A Impact Socket Adapter and Reducer Set, Chrome Vanadium Steel | 5-Piece Set for Impact Driver Conversions : Everything Else   piggy back 1/4 to 3/8 then 3/8 to 1/2

  • Thanks 1
Posted
59 minutes ago, harmony said:

According to the service manual there should be around 15 in.lb. of torgue.

 

That is the preload on the bearings, not the nut torque.  Preload is basically how much effort is takes to spin the pinion (without the axle shafts installed). 

 

The torque on the nut should be much higher. 180 ft/lbs per the Plymouth manual

Posted
1 minute ago, Sniper said:

 

That is the preload on the bearings, not the nut torque.  Preload is basically how much effort is takes to spin the pinion (without the axle shafts installed). 

 

The torque on the nut should be much higher. 180 ft/lbs per the Plymouth manual

ohhhhhhhh, ok  So that makes more sense as to why it seemed pretty tight coming off.  I'll tighten it up to that spec.  There was no mention in the 48 Chrysler service manual about that torque on the torque page at the back, or in the section that covers the pinion gear.  One would think it should be the same.

 

So if I just pulled the axles to change the seals, and the pinion yoke to replace the pinion seal, would it be safe to say that the preload hasn't changed from what it was before?

 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use