Front hub bearing replacement

DFoley · Post by **DFoley** » Tue Jun 23, 2015 12:06 pm

OK, so I have tasked myself with changing the front inner and outer hub bearings on my '51 M38. I have read and reread the procedure in the TM 9-8012 & TM 9-1804B multiple times. While I have never attempted this before it seems straight forward and simple. My concerns however, are that I don't have the specialized tools required to do the job. I don't have a wheel bearing nut wrench to get the hub off nor do I have the remover and replacer or the screw tools to get the old bears out and install the new bearings. Furthermore, I'm not exactly sure what sort of "suitable puller" tool I need to remove the shaft drive flange. My questions are: should I purchase the specific tools that are mentioned in the TM's? If so where do I get them? Do the online jeep parts stores have these tools? Or are there modern better equivelents to these tools that I can get at my local NAPA or other auto parts store? Finally, is this something I should even be trying? I'm not a mechanic, but I'm not a complete idiot either. I can read and follow instructions. Or is this something that is best left to someone who has experience doing this sort of procedure? As I've mentioned in past posts, one of my main motivations in having one of these older mechanical jeeps is to learn the basics of how an automobile works and how to fix and repair them as necessary. But I also realize there are certain aspects of any vehicle that are best left to persons with specialized experience and skills. What do you think?

4x4M38 · Post by **4x4M38** » Tue Jun 23, 2015 7:29 pm

Hi Dan,
The nut socket is available as a commercial socket, or can be
bought from several M suppliers. That version is not expensive.
The other tool I believe is known as Bertha the hub puller among
other nomme deguerre.. I have seen it on EBay among other places.

I need to do the same thing as you as well as go through the
spindles. Since my jeep is not a needed daily driver I can
take it apart and take my time getting it back together.

I hope you beat me to it so I can learn by watching you!

Take care,
Brian

Post by **wesk** » Tue Jun 23, 2015 7:29 pm

Well Dan, being from Texas is one point in the right direction. It's not that tough. Google up the dozen or so U-tube shows that detail and illustrate how to do it. A lot of special tools you do not need. It is foolish to own a jeep and not own the $12 socket for the front bearing nuts.

Use the civilian manual I have the chapter on the front axle at:
http://www.willysmjeeps.com/v2/modules. ... _album.php

As you remove each piece lay it on a table in the order it was removed. If you lay it on the floor sooner or later you will kick the parts all over and loose the order of assembly of those parts.

A plain 8" or 10" long common screw driver and a pair of channel lock pliers are all you need to pop the axle hub cap and the drive flange. Most drive flanges will pop right off with a tap from a light hammer on the edge or insert tip of screw driver in between the edge of the flange and the hub and tap it. Be careful to catch any shims and line them up on the table in their order of assembly. Keep a watchful eye to learn which type front axle you have (Rzeppa, Bendix, or Spicer). Follow the directions in the civvy manual for the one you have.

When you need to find a tool just google it. IE google "Jeep front hub nut wrench" You'll get this list: https://www.google.com/webhp?sourceid=c ... t%20wrench

Here's one on Ebay:

This can be operated with a short length of 5/16" or 3/8" steel rod or a 1/2" drive ratchet.

skyjeep50 · Post by **skyjeep50** » Wed Jun 24, 2015 7:31 am

This task is probably one of the more grubby maintenance jobs due to the large amounts of grease found in the front hubs but overall, "tuning up" the hubs including wheel and knuckle bearing maintenance is one of the most important and most neglected. There really aren't many difficult repair jobs on a M38 if you have the right manual to follow and are careful. As for leaving it to an "expert", there are likely none to be found. You might be able to find someone familiar with older jeep-type vehicles at a back alley independent garage somewhere, perhaps a military trained mechanic but that would be a lucky find. The people down at the current Jeep dealership will just scratch their heads. The best mechanic to be found is the one you will become if you get "hands-on" and work through repairing and maintaining your jeep. I was probably in the same position as you when I got my jeep, mostly a farm mechanic, a wrench turner. Now I'm a better class of wrench turner with M-series jeep knowledge! One thing I found to be very handy in rebuilding my M38 was a parts washer. Kind of a specialized tool, takes some room but is invaluable for cleaning greasy parts and a whole lot safer than a 5 gallon open bucket of solvent.

SteveJ · Post by **SteveJ** » Fri Jun 26, 2015 11:25 am

Did mine a few years ago. straight forward job. a bit messy but thats what those bearings are all about just prepare and take your time.

DFoley · Post by **DFoley** » Tue Jun 30, 2015 4:59 pm

Well I got this dirty job done. It took me 3-4 hours, but I went slow and methodical. Turns out it was rather easy, but a messy job! Hardest part was getting the old bearing cups out and the new ones in. I don't have a press so I used a variety of punch tools and slowly worked my way around the edge of each cup gently tapping them out or in. Seemed to work great. My jeep drives much smoother and tighter now...alleviated the slight front end shimmy that had been developing over the past few months. I feel like I added one more notch to my amature mechanic belt.