Question on bolts sizes and the rear Axle vent

Geronimo · Post by **Geronimo** » Wed Oct 10, 2018 3:32 pm

Hi,
First off I'm not a very knowledge car guy, rebuilt a 76 superbeetle back in high school and that's about it. In fact it was my milsurp firearms collection that somehow brought me to this project. So anyway, I've been slowly working on a M38a1 restoration that i picked up from someone else. This has led to a degree of confusion on several occasions, which thankfully has been resolved though by the knowledge herein contained.

This time though no amount of Google-fu, Ord manuals, or ghosting the forums has helped.

What size, thread, and length are the bolts that hold the transfer case to transmission? I couldn't find them in any of the manuals and the one on the left is the wrong size.

Secondly, could someone please tell me where the rear differential/ axle vent is? I know about the drum zerks and and such, but my differential is leaking from the drain plug and im fairly certain that the breather is to blame. Anyway I cant find it anywhere...

Thankyou for any help, it's much appreciated.[/img]

Post by **wesk** » Wed Oct 10, 2018 4:11 pm

This time though no amount of Google-fu, Ord manuals, or ghosting the forums has helped.

What size, thread, and length are the bolts that hold the transfer case to transmission? I couldn't find them in any of the manuals and the one on the left is the wrong size.

M38A1 ORD 9 SNL G-758 Page 198, 3 1/2" from the top of the page.

1 each bolt, cap, hex-hd, S, cd- or zn-pltd, 3/8"-16NC-3x1"

4 each Screw (same as bolt), cap, hex-hd, S, cd- or zn-pltd, 3/8"-16NC-3x 1 1/8".

Secondly, could someone please tell me where the rear differential/ axle vent is?

M38A1 ORD 9 SNL G-758, Page 224 shows it in the illustration Item letter "L". It is listed on page 231 under "1105.5 Ventillation"

There is also a good shot in the TM 9-08014 M38A1 operator's manual on page 334.

Looks like your cover has either tossed the fitting and valve and welded the hole shut or has substituted a different cover. It was about 4" or so above the drain plug.

dpcd67 · Post by **dpcd67** » Wed Oct 10, 2018 7:44 pm

No one can own, operate, or maintain a military vehicle without a complete set of TMs; so before you do anything, get a set, including the SNL, which will tell you all the bolts, nuts screws, pins, and washers on your vehicle, with size, material, finish, etc, for each one.
And read them; I do every day for WW2 Jeeps, M38s and Dodges; not kidding.

Geronimo · Post by **Geronimo** » Wed Oct 10, 2018 9:08 pm

Thanks for the help and suggestions guys. I will definitely place an order for reading materials. I’ve been using a tablet and pdf file but hey having one in the head could never hurt.

Wesk your reply lead me to another realization though, that’s a Dana 41 not a 44. As I scrubbed off the paint to no avail I noticed the configuration discrepancy. Eventually I’ll change it out, but for time being I at least know where the breather should be. So, the puzzle of randomness I encounter on this project continues.

45auto · Post by **45auto** » Wed Oct 10, 2018 9:16 pm

I was about to post a reply saying it looks like you have a Model 41 rear axle swapped in.

The vent for this axle is on the drivers side on top of the tube, right by the leaf spring U bolts. It is not a valve but a very small hole that most often is covered / plug with dirt and grease. You will most likely have to wire brush the area to locate it.

Geronimo · Post by **Geronimo** » Wed Oct 10, 2018 9:26 pm

Lol, I can’t scrub anymore tonight... need a beer at this point. Hey 45auto, you near Coweta county by chance?

RonD2 · Post by **RonD2** » Wed Oct 10, 2018 9:28 pm

10-4 on the manuals in the head Mr. Geronimo!

This is my set up:

This forum is a wonderful resource --- and if you don't do your homework they tend to eat your lunch........

Post by **wesk** » Wed Oct 10, 2018 10:14 pm

You might find this link interesting.

https://www.thecj2apage.com/forums/rear ... page2.html

Have you checked the gear ratio of your 41? I would. It may not be 5:38 to 1

45auto · Post by **45auto** » Thu Oct 11, 2018 9:24 am

I'm not too far from you--less that 2 hours away with light traffic. Coweta Co is within the Region I cover.

Geronimo · Post by **Geronimo** » Thu Oct 11, 2018 5:54 pm

RonD2 wrote: This is my set up:

Don’t give me anymore ideas, the neighbors are already looking at me funny.

Wesk, that picture is dynamite! Found the thing almost right off the batt, but boy was it concealed. It perfectly matched the rest of the axle “patina” and had to be gently chiseled out. That’s the good news, the bad is that the threads in the transmission for that mounting bolt are stripped out. The 3/8 hardly even grips and my removal of the other bolt has only made the leak worse. Idk, being a steel case I could oversize the bolt maybe. I have a good tap and die set with some experience in its use but it may be a project best left to a real mechanic.

Auto45: Which leads me to why I asked about your location. You wouldn’t happen to know any mechanics experienced in the Willys in our general area would you? I admit my limitations and some of the last few things on this vehicle should be left in more capable hands.

Here’s the beast

Also, I don’t know anything about gear ratios so that’s something I’ll have to look into.

Post by **wesk** » Thu Oct 11, 2018 6:53 pm

Also, I don’t know anything about gear ratios so that’s something I’ll have to look into.

The thin stamped tag under the top center cover bolt is the ratio tag. I don't
see a tag on your photo's cover. Means you'll have to rotate the axle or brake drum 360 degrees and then measure how many degrees the drive shaft hook- up rotated.