Dana 44--I found one. Swap questions....

[coolwind57]

50 minutes ago, schardein said:

Yes, That centering pin actually locates the axle on the leafspring. The U-bolts and plate secure it.  Replacement pins are available with different shank diameters and head diameters. The shank diameter should match the hole in the leaf springs. The head diameter should match the recess in the spring mounting pad on the axle.   You should always check for a proper fit. If the head diameter is too small, it will allow the axle to shift on the leafspring. If the head length is too long it could bottom out in the leaf spring pad and prevent proper tightening of the U bolts.

Very good.  i suppose I won't know the shank diameter until I pull my D35 off the springs.  Well, that kinda kills my plans of doing the swap in a couple of hours (or maybe even a day).  

 

Now....i suppose I need to find a supplier.

[derf]

The pin is just a bolt with a round head.  There's a standard nut on the other side.

 

Be very careful if you take it apart.  The springs are under tension.  I use a couple of C clamps on either side of the pin to hold the pack together.  I've also put the whole pack in a bench vice.  Then it's just a matter of taking off the nut and the pin comes out.

 

You should be able to get a good sense of the size of the bolt without removing the nut if you look at it closely.  It's standard SAE: 5/16", 3/8", 7/16" or whatever.

[ghetdjc320]

7 hours ago, derf said:

I've seen individual clutches in the packs break inside of a D35.  All that does is make it whine a little.  It acts like an open differential when the clutch packs wear out.  The worn metal dust floating around in the gear oil doesn't help your bearings, which can also make some noise when they start to go bad.

 

While the axle is out, it's not a bad time to replace seals and the outer axle bearings no matter what you do.

 

A drivetrain shop should be able to figure out what's good and what's bad and get you set up.  If you really want a working limited slip, you can either get the unit rebuilt or spend a little more and get a better limited slip.  Eaton makes a TrueTrac that I use and it's great.  There's another company that started making one very similar in the last few years.  I forget the name.  It's less expensive than the TrueTrac but seems to be getting good reviews.

I think the other one is the power trax grip pro

[derf]

26 minutes ago, ghetdjc320 said:

I think the other one is the power trax grip pro

That sounds right.

[schardein]

I can't recall where I got my leaf spring center bolts last time I ordered them.  New ones are often quite long, the idea being you are assembling a loose spring pack.  Once tightened down, hacksaw off any length that sticks out past the nut.  But like Derf said, secure the spring with a C-clamp to keep it together.

 

Surely someone on here has a set of standard springs they can check the bolt diameter on.

 

Here is one source:

https://www.rockauto.com/en/tools/suspension,leaf+spring+hardware,leaf+spring+bolt,10353

 

Another.  A local store probably has some in stock, you'll just need to find a counterperson who knows what you are talking about.

https://www.oreillyauto.com/shop/b/suspension---steering-16778/coil---leaf-springs-16803/spring-center-bolts---universal-18243/5ae38b679375

 

I don't know offhand if the D35 and D44 axle tubes are the same diameter.  Even if they are, the heavy duty suspension used a larger diameter u-bolt.  My point is you may need or want new u-bolts.  

 

If the MJ is your only ride, you might want to look at the brakes and brake lines on the new axle and order parts/repair as needed before the swap.  Other items to consider: new center pins, u-bolts, cover gasket and gear oil.  Any signs of leakage at the pinion yoke?  Now would be the time to replace the pinion seal, and pinion yoke if the seal surface shows wear.  I would also inspect for leakage where the axle shaft enters the axle at the brake backing plate (axle shaft seal).

 

Have you had your leaf springs off before?  With the axle sitting on top of the springs, you will have to drop one side of the spring (front or back, doesn't matter) to remove the old axle and install the new. One frozen leaf spring bolt can turn an afternoon job into an all weekend job.

[Pete M]

I used grade 8 cap head bolts (round head and uses an allen wrench) for center screws on my MJs. 

[ghetdjc320]

2 hours ago, Pete M said:

I used grade 8 cap head bolts (round head and uses an allen wrench) for center screws on my MJs. 

Great suggestion, I’ve used the same and it works great. 

[Pete M]

on the topic of ubolts and plates, it's possible there's something up where you'll be fine if you keep them together but just can't mix 35 bolts with 44 plates and vise versa.  I'm not at home to verify, but I remember having trouble when I picked up my trailer.  I had to supply the leafs and we assembled it on the spot and I remember having trouble getting the bolts to go through the plate.  He dug around for the other set of bolts and everything worked ok.  Problem is that I don't remember the specifics.   

 

anyone have a set of both lying around to compare?

[ghetdjc320]

I’d just grab some new ones from ruffstuffspecialties. Dana 35 and Jeep Dana 44 axle tubes are often the same size depending on the year. U bolt plates should be very close. A bit of filing or grinding should get them to fit

[ghetdjc320]

https://www.ruffstuffspecialties.com/catalog/merchant.mvc?Screen=PROD&Store_Code=ruffstuff&Product_Code=UB275&Category_Code=U-BOLTS

 

These should work fine but measure your axle tube diameter where the springs bolt on. 

[coolwind57]

12 hours ago, schardein said:

I don't know offhand if the D35 and D44 axle tubes are the same diameter.  Even if they are, the heavy duty suspension used a larger diameter u-bolt.  My point is you may need or want new u-bolts.

 

7 hours ago, ghetdjc320 said:

 Dana 35 and Jeep Dana 44 axle tubes are often the same size depending on the year. U bolt plates should be very close. A bit of filing or grinding should get them to fit

 

9 hours ago, Pete M said:

on the topic of ubolts and plates, it's possible there's something up where you'll be fine if you keep them together but just can't mix 35 bolts with 44 plates and vise versa.  I'm not at home to verify, but I remember having trouble when I picked up my trailer.  I had to supply the leafs and we assembled it on the spot and I remember having trouble getting the bolts to go through the plate.  He dug around for the other set of bolts and everything worked ok.  Problem is that I don't remember the specifics.   

 

anyone have a set of both lying around to compare?

 

13 hours ago, schardein said:

Any signs of leakage at the pinion yoke?  Now would be the time to replace the pinion seal, and pinion yoke if the seal surface shows wear.  I would also inspect for leakage where the axle shaft enters the axle at the brake backing plate (axle shaft seal).

 

Have you had your leaf springs off before?  With the axle sitting on top of the springs, you will have to drop one side of the spring (front or back, doesn't matter) to remove the old axle and install the new. One frozen leaf spring bolt can turn an afternoon job into an all weekend job.

 

Just went out and measured both axle tube diameters.  D44= 2-3/4"  D35= 2-1/2".  

 

I also measured my truck's axle plates/brackets (as best I could with the D35 still on the truck).  It appears that the D44 plates that I got from the seller are the same.  The ends of my U-bolts seem to match the D44's hole diameters, although I could not get the pairs to fit into them as I held them up to slid on.  I think this is due to the slight distortion of the U-bolts having been torqued tight, but I'm not sure.  I was laying on cold, wet ground so discomfort trumped some accuracy in my inspection here.  

 

It would had been interesting to check the diameter of the D44's U-bolts.  I think the guy cut them off to remove the axle anyhow, so I didn't even think of grabbing them.    

 

This Dana 44 was full of road grime, but there is no evidence of any wetness at pinion yoke or near backing plate.  He must have had some pretty significant engine/trans leaks, but the road grime appeared dry, overall.  I spent an hour or so scrubbing the axle last night, with more cleaning later today.  I pulled the cover and although the lube seemed low and dark, the gears looked fabulous.  Nice and shiny mating surfaces and no distortion. 

 

I had mentioned earlier that the limited slip works at least when spinning the yoke by hand.  

 

Good stuff here, guys.  Thank you for sharing your knowledge.   I'll report back as things progress.    

[schardein]

6 minutes ago, coolwind57 said:

Good stuff here, guys.  Thank you for sharing your knowledge.   I'll report back as things progress.    

Keep us updated.  

 

Here is the current state of my MJ Dana 44.  It was a 3.07 ratio, I am changing to 3.73 gears with a Truetrac limited slip diff.  New bearings & seals on the diff and axle shafts.  New brakes & new hard lines.  Just got the brake backing plates back from being powdercoated, so can begin bending the lines.

 

I'm glad to hear the D35 spring plates will work, because the original D44 spring plates are heavily rusted, slightly distorted, and one of them the shock mount stud is damaged.

[coolwind57]

4 hours ago, schardein said:

Keep us updated.  

 

Here is the current state of my MJ Dana 44.  It was a 3.07 ratio, I am changing to 3.73 gears with a Truetrac limited slip diff.  New bearings & seals on the diff and axle shafts.  New brakes & new hard lines.  Just got the brake backing plates back from being powdercoated, so can begin bending the lines.

 

I'm glad to hear the D35 spring plates will work, because the original D44 spring plates are heavily rusted, slightly distorted, and one of them the shock mount stud is damaged.

 

Same here, the D44 spring plates are a lot worse condition than my originals.  Are you still planning on running the Load-sensing valve?  I do have the diff cover bracket for it if you need it.  I'm not going to use it.

 

I'm going to go ahead and pull my axle shafts.  I have found evidence of one outer seal leaking, coating the brake area.  I'm off now to look up how to do it.  I think I had pulled axle shafts in the past, but I hadn't done one with limited slip before.  I was really kind of hoping to not do a complete rebuild with new bearings and such.  And rebuilding that LSD....oh boy.  It would be pushing my comfort level.

[coolwind57]

Ok...looks like seal removal requires removal of an retainer as well as the bearing.    This might get interesting.

[Pete M]

If it's like the ford 9", I had to get a shop press those off/on.  wasn't much money but irritating I couldn't do it myself.

[coolwind57]

2 minutes ago, Pete M said:

If it's like the ford 9", I had to get a shop press those off/on.  wasn't much money but irritating I couldn't do it myself.

These D44s aren't C-clip or anything are they, Pete?  Just held in by the backer plate 4-bolts, right?

[Pete M]

yup.   

[schardein]

Getting the axle shafts out is just removing the brake components, and removing the four nuts and bolts holding the backing plates on.  Sometimes the axle shaft will pull right out, sometimes it helps to have a slide hammer to persuade it.

 

Once out, you have to remove the bearing retainer.  I center punch it, start with an 1/8" drill to get a centered hole started, then move up to a bit about the same size as the width of the ring.  Drill about halfway through (don't drill the axle shaft!) and put a chisel on it and give it a good whack.  The retainer will split and slide off.

 

The bearing must be pressed off.  Even some smaller shops won't have a press with enough "length" or a wide enough platform to do this work.  I use a puller specifically for the job (blue part in the pic).  They are rather expensive.  https://www.amazon.com/Yukon-Gear-Axle-YT-P70/dp/B0078U9JSY/ref=au_as_r?_encoding=UTF8&Make=Jeep|42&Model=Cherokee|347&Year=1991|1991&ie=UTF8&n=15684181&s=automotive&vehicleId=6&vehicleType=automotive

 

With this tool, even my HF press can do the job, although it's barely tall enough.  It's difficult to get the bearing off without damaging it, without a puller like this.  I've damaged one even with this puller.  Once the bearing is off, the seal slides off.

 

Clean up the shaft, replace any damaged lug studs.  Slide on the retainer plate (I ordered new, since mine were pretty rusty), slide on the new seal (smear a film of grease on it first)(make sure it faces the right way!), press on the new bearing.  I place the shaft in my deep freezer overnight, and heat the bearing for 30 min to make assembly easier.  Then press on the new bearing retainer, and reassemble the axle.

 

Most likely, do-it-yourselfers will need to take the shafts to a machine shop or local repair shop to have the axle bearings and seals replaced.  I searched for work arounds before purchasing the puller, and didn't find any.  This MJ axle is my fourth Dana 44 rebuild, so I'm getting my money out of it.

 

EDIT: I meant to add that I have re-used axle shaft bearings after replacing a seal.  But many shops will frown on this, as they can't guarantee they won't damage the originals during removal, and that's a valid concern.

[schardein]

1 hour ago, coolwind57 said:

 

Same here, the D44 spring plates are a lot worse condition than my originals.  Are you still planning on running the Load-sensing valve?  I do have the diff cover bracket for it if you need it.  I'm not going to use it.

Thank you for the offer.  My axle does have the bracket and I plan to retain my LSV.  But I'm sure someone here will be able to use it, rare part for sure.

[schardein]

1 hour ago, coolwind57 said:

I'm going to go ahead and pull my axle shafts.  I have found evidence of one outer seal leaking, coating the brake area.

On an axle this old, new seals are a good idea, but be sure it isn't just a leaky brake wheel cylinder.  Replacing axle shaft seals is way more involved (and expensive) then replacing a wheel cylinder.  That's a good thing about drum brakes- replacement components are inexpensive, except sometimes the drum, although many times they can be inexpensive too.

[DesertRat1991]

 

7 hours ago, schardein said:

Keep us updated.  

 

Here is the current state of my MJ Dana 44.  It was a 3.07 ratio, I am changing to 3.73 gears with a Truetrac limited slip diff.  New bearings & seals on the diff and axle shafts.  New brakes & new hard lines.  Just got the brake backing plates back from being powdercoated, so can begin bending the lines.

 

I'm glad to hear the D35 spring plates will work, because the original D44 spring plates are heavily rusted, slightly distorted, and one of them the shock mount stud is damaged.

 

I wish I had gotten my tubes welded and the plug welds reinforced when I was torn down.  Got it all painted, built and installed then discovered it was weeping from the pass side tube.  It's cheap insurance for an axle of unknown mileage and work history. 

[coolwind57]

2 hours ago, schardein said:

Getting the axle shafts out is just removing the brake components, and removing the four nuts and bolts holding the backing plates on.  Sometimes the axle shaft will pull right out, sometimes it helps to have a slide hammer to persuade it.

 

Once out, you have to remove the bearing retainer.  I center punch it, start with an 1/8" drill to get a centered hole started, then move up to a bit about the same size as the width of the ring.  Drill about halfway through (don't drill the axle shaft!) and put a chisel on it and give it a good whack.  The retainer will split and slide off.

 

The bearing must be pressed off.  Even some smaller shops won't have a press with enough "length" or a wide enough platform to do this work.  I use a puller specifically for the job (blue part in the pic).  They are rather expensive.  https://www.amazon.com/Yukon-Gear-Axle-YT-P70/dp/B0078U9JSY/ref=au_as_r?_encoding=UTF8&Make=Jeep|42&Model=Cherokee|347&Year=1991|1991&ie=UTF8&n=15684181&s=automotive&vehicleId=6&vehicleType=automotive

 

With this tool, even my HF press can do the job, although it's barely tall enough.  It's difficult to get the bearing off without damaging it, without a puller like this.  I've damaged one even with this puller.  Once the bearing is off, the seal slides off.

 

Clean up the shaft, replace any damaged lug studs.  Slide on the retainer plate (I ordered new, since mine were pretty rusty), slide on the new seal (smear a film of grease on it first)(make sure it faces the right way!), press on the new bearing.  I place the shaft in my deep freezer overnight, and heat the bearing for 30 min to make assembly easier.  Then press on the new bearing retainer, and reassemble the axle.

 

Most likely, do-it-yourselfers will need to take the shafts to a machine shop or local repair shop to have the axle bearings and seals replaced.  I searched for work arounds before purchasing the puller, and didn't find any.  This MJ axle is my fourth Dana 44 rebuild, so I'm getting my money out of it.

 

EDIT: I meant to add that I have re-used axle shaft bearings after replacing a seal.  But many shops will frown on this, as they can't guarantee they won't damage the originals during removal, and that's a valid concern.

 

I did remove my shafts today. 

 

My wheel cylinders were pretty new, as they only have some surface rust along the top.  The bottom end, as installed were still unrusted.  This leads me to believe that perhaps the PO had removed and replaced the wheel cylinder to fix his now obvious leaking.  The seals looked pretty bad.  I had to use some persuasion to remove one axle, sure because that seal was so rusty and seized up.  The other came out quite easily.

 

I was expecting the worst for the bearings, but they look great.  Races look great too.  My plan is to take my axles to a local shop and have them pull and replace.  If they are concerned with the bearings, then I'll consider replacing them at that time.  Sure appreciate your help.

 

25 minutes ago, DesertRat1991 said:

 

 

I wish I had gotten my tubes welded and the plug welds reinforced when I was torn down.  Got it all painted, built and installed then discovered it was weeping from the pass side tube.  It's cheap insurance for an axle of unknown mileage and work history. 

 

Good idea!  I've heard of tube welding.  But what do you mean by plug welds reinforcement?  The only plug I can think of that you mean is the diff cover.

[Minuit]

Related, but unrelated: I had suspicions that I had a leaky wheel seal too. Every now and then I'd have a black drip under my right rear wheel. I found out not long after that it was actually the 3 year old wheel cylinder puking its guts out, which turned black after mixing with brake dust. The very next day I went to the junkyard and came back with a full ZJ rear disc setup.

 

I guess I better get after it with my D44 build if you're that far ahead of me Greg We are doing literally identical projects, after all.

[ghetdjc320]

People refer to the two round holes in the housing near the axle tubes as “plug weld” holes. Many have indeed plug welded that hole but that is where a case spreader would normally go. Not many d44s have an axle tube spinning problem like the 8.8s. You can still weld the tubes if you like if you can get a good weld on the pumpkin to tube area. I would recommend though that you don’t use the case spreader holes and fill them up with “plug welds”. 

[ghetdjc320]

You can reference this photo. The red x is not a plug weld. It’s hard to see for sure but it looks like this housing does have some plug weld provisions (highlighted in the green circles)