Replace M939 Front Axle Seals and Boots DIY

[Ford Mechanic]

I've deleted the CTIS on my truck does anyone know if the next time I have to tear it down if I can revert to the older A1 style seals? Instead of the cost and pain in the but on install that the CTIS ones are, or is there a good reason that I shouldn't?

 

[brazengoat06]

I've actually had good luck with the zipper type. The first one took a while to get one but once you teach yourself the proper way to install them you can get them on in about 15 minutes. IMO I wouldn't take the knuckles apart unless I had to.

 

[Cobra03]

Would this be the same for a M923A2?

 

[brazengoat06]

Would this be the same for a M923A2?

Are you referring to the boots or the axle seals? Or both?

 

[Cobra03]

Are you referring to the boots or the axle seals? Or both?

Starting at post #35.

 

[brazengoat06]

Not necessarily, you will have to deal with the added CTIS. Also the seals are different to my knowledge. I believe the only thing that is the same exact process is the boots.

 

[adamsoffroadperformance]

^^^^^^ correct for the most part. the pinion seals are the same too

 

[acesneights1]

if anyone could direct me to the proper TM for the torque specs.
Saw this vid on youtube. Would have done a few things different but it is very good at showing what's in there but I would support the truck better and not use a hammer on the axle tube seal. Also I would suggest the proper sockets.
https://www.youtube.com/watch?v=Q3Z6_ySV8D0

 

[acesneights1]

the washer in front of the axle tube seal, chamfer facing in or out. I missed that when taking it apart and see no reference in the TM.

Edit: as per Adam's performance and Rockwell off road it faces out toward axle joint however Rockwell said most trucks don't even have that chamfer .

 

[acesneights1]

OK, just finished the same job. Rather than do my own thread, I'm gonna add some notes to this one. First off the TM's are a royal PIA.
This TM has all the info but it's scattered about.
http://www.steelsoldiers.com/showth...eries-Trucks&p=1451111&viewfull=1#post1451111

Basically...The upper steering arm studs are 150-170 ft/lbs which felt like alot to me for the size of the stud. I would stay to the 150 side of that.
The 9 spindle studs are 130 ft/lbs. The spec is not under any of the knuckle repair pages. Found it under the Brake Spider repair.
page 0427-1 Front Brake spider and actuator repairfrom the TM I posted above.

The wheel bearing nuts commonly referred to as the spindle nuts are found on page 0479-1 Front Hub Maint.

Finding this info took me awhile so I hope it helps someone else in the future. My suggestion is to install the boot clamp on the boot then put the boot on the axle BEFORE you put the knuckle back on and leave it loose enough to clock it once the knuckle is on. Then once the knuckle is back on you can clock it and then turn knuckle to the right and tighten the boot clamp.Much easier this way. Then I would do the 12(?) screws for it before you put the steering arm back on.
The job was time consuming but pretty easy IMHO. Hardest part was getting the axle tube seal out and once I made the proper tool for my slap hammer it popped right out. You will not get it out with a lady foot. Make sure you catch the back of the seal only as the axle tube has a lip inside.

 

[simp5782]

Thanks. Also to clarify what I'm trying to do, I'm trying to remove the encased seal assembly from the axle housing and not the seal from the seal housing. Thanks for any tips.

Thought i would add to this since i had to help someone who didn't know the difference between a seal and the retainer.

I will also add this.

M54,809,M939A0/1 uses the same seal and retainer.
M939A2s use a double lipped seal and a different retainer. Retainer difference nor the seal is listed in the TM as being different. The retainer shown in the video is the deeper A2 style.

https://youtu.be/FkC1aSqRaxs

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