LMTV FMTV front axle outer seal replacement

[Keith Knight]

After replacing all the hub and CTIS seals last winter I have developed a leak in the front axle outer seal. Oil is dripping at the bottom of the passenger side king pin area.
Looks like #59 seal. Mid west says there are requires 2 at each end but I only see 1.
What’s the best way to replace the seal or seals? Anyone know of a video showing it?

 

[MatthewWBailey]

After replacing all the hub and CTIS seals last winter I have developed a leak in the front axle outer seal. Oil is dripping at the bottom of the passenger side king pin area. View attachment 926721
Looks like #59 seal. Mid west says there are requires 2 at each end but I only see 1. View attachment 926722
What’s the best way to replace the seal or seals? Anyone know of a video showing it?

The 24P parts TM only shows quantity 1. I have to do this same job...

 

[GeneralDisorder]

Two per truck maybe.

If you are going that far in, get new front axle shaft u-joints.

 

[Keith Knight]

Good point. Also most likely replacing #61 sleeve bushing. He insisted 2 on each side and sold me 4. I was there in person and he saw the problem and truck. Going to call and have him point it out to me on the drawing.

 

[GeneralDisorder]

That sleeve looks like it's a discardable sealing surface sleeve. Guessing it's pressed or shrunk on probably with 609 Loctite so it doesn't move or spin. That will be entertaining. If it's on there with green sleeve retaining compound (609) you will have to heat it to get it off and usually an induction heater and a dead blow with a driver made from some pipe, etc will be required for installation. Did a lot of that working on industrial pumps and compressors.

 

[Keith Knight]

I know exactly what you’re talking about. I’ve even had to cut them with a reciprocating saw and chisel them out. That doesn’t sound fun. Maybe have new ones on hand check tolerances and if needed then replace.
Any idea if the u joint is a common Dana / spicer part number?

 

[GeneralDisorder]

I know exactly what you’re talking about. I’ve even had to cut them with a reciprocating saw and chisel them out. That doesn’t sound fun. Maybe have new ones on hand check tolerances and if needed then replace.
Any idea if the u joint is a common Dana / spicer part number?

The u-joint is a Rockwell/Meritor/Axle Tech CP750N1



Do see some for sale..... https://www.ebay.com/itm/NEW-ROCKWE...NT-P-N-CP750N1-M35-FREIGHTLINER-/143378560714

Probably can cross to something cheaper but with how much work that is to get to.... I've greased mine and the seals don't look great but I'll wait till I have to do those inner hub seals.

For the sleeves - we would hold the shaft (by an assistant's hand for small ones and by overhead crane for big stuff) upside down on a pointed rod welded to a piece of plate and heat the sleeve with a rosebud (or several for really big ones) till red hot and they will just fall off onto the pointed rod (this way they are contained and don't roll off the table into the nearby bucket of greasy rags ). Welding bench under all of it of course so nothing is flammable.

 

[Keith Knight]

I have a friend that modifies these axles for monster trucks. I’ll see is he has a better source and experience doing this job.

 

[Castle Bravo]

There are 4 total on a truck, 2 per side. They are on both sides of the U-Joint. One is the innermost item on the hub and the other is outermost on the axle tube. It is not shown in the TM on the page above, but is shown on the page with the axle tube.

There is an older 2 piece and a newer 1 piece seal. If you have the two piece, sometimes one part gets stuck on the axle shaft.

 

[Keith Knight]

I’m so confused the seal, washer and sleeve bearing are shown that go in the axle housing. Where is the other seal go.

 

[MatthewWBailey]

There are 4 total on a truck, 2 per side. They are on both sides of the U-Joint. One is the innermost item on the hub and the other is outermost on the axle tube. It is not shown in the TM on the page above, but is shown on the page with the axle tube.

There is an older 2 piece and a newer 1 piece seal. If you have the two piece, sometimes one part gets stuck on the axle shaft.

Looks like 9 and 59 are the same part number..

 

[Castle Bravo]

I’m so confused the seal, washer and sleeve bearing are shown that go in the axle housing. Where is the other seal go.

They don't go in the axle housing, they go on the end of the spindle - The ones that go in the axle tube are shown in the post above this one.

 

[GeneralDisorder]

It's item 10 in the A1 manual.

 

[Keith Knight]

Look closely that’s the same drawing just with the axle shaft. 59,60,61 are identical to 8,10,11 and identical part numbers. They are in the exact same order. So only 1 seal one thrust washer and one bushing sleeve. Per side not 2 on of each side.

 

[GeneralDisorder]

No there is two per side. One on either side of the u-joint. Two shafts - one into the axle tube, and one into the hub. Same seal on either side. So one per side, AND one per drawing. Total of four.

 

[Keith Knight]

Those drawings don’t show that. The seal, thrust washer and sleeve are in the same order in both drawings. Indicating they go into the axle housing. If they went into the hub they would be in reverse direction.

 

[GeneralDisorder]

That's not what I see. I see two sets - one to keep the oil in the axle tube, and another set to keep the oil in the hub. Separated by the u-joint.

 

[Keith Knight]

So that would mean I need 4 of the sleeve bushings as well.

 

[Ronmar]

So that would mean I need 4 of the sleeve bushings as well.

Yep, seal washer and bushing on either side of the ujoint(outer end of axle housing/inner end of spindle tube)

IMO if you are going to pull the hub down to the point where you can access that inner spindle bushing and seal, you can pull the axle shaft, overhaul the ujoint and do at a minimum the inner seal on the end of the axle housing… all the hard work is getting to the point where you can pull the axle anyway, might as well while you are in that deep…

 

[Keith Knight]

This is going to suck!!!!