M38 Front Brake Tee

RonD2 · Post by **RonD2** » Wed Aug 07, 2019 4:41 pm

After much elusive research, I haven't been able to find a post discussing or a photo showing how the front brake tee is mounted on the M38. Came across some videos showing a bracket welded to the axle tube with the tee bolted to it, but they might be MB/GPW or CJ axles?

Mine doesn't have a welded bracket, the tee is bolted directly into the axle tube in a threaded hole (that I think could use a dab of sealant when I re-assemble it):

Is this correct for the M38 axle? I sure hope it's not Bubba.....

I did note that page 113 of the M38 Reference Guide says the tee bolts straight to the tube via the bolt, but no photo, so maybe it's good M38 and I answered my own question.....just trying to confirm.

As always, thanks!

4x4M38 · Post by **4x4M38** » Wed Aug 07, 2019 9:04 pm

Ron,
This is what mine looks like:

https://www.ebay.com/i/323491439949?chn ... gLNHvD_BwE

Post by **wesk** » Wed Aug 07, 2019 9:11 pm

Is this correct for the M38 axle?

YES

There are no M38 manual photos that show the tee mounting clearly.

And you saw Ryan's reference. But the most obvious reference is the TM 9-8012 Par. 245c. (1) (b) at the bottom of page 289!

I believe this very clearly states the bolt goes directly into the hole in the axle tube.

RonD2 · Post by **RonD2** » Wed Aug 07, 2019 9:28 pm

Dang it! I hate when that happens!

I'm pretty used to it happening anyway, just not so doggone quick.

Thanks Wes! You da Man!

Hey Brian, yes, am using the correct angled tee on the front axle (not the same tee as the rear axle).

Although my photo might show it angled the wrong direction......I just stuck it on there so I wouldn't lose it while I fart around for awhile.....

Post by **wesk** » Wed Aug 07, 2019 10:04 pm

I did find photos of the rear side of my front axle before the engine went in!

Also the MB does have the front axle rear side illustrated in TM 9-1803B pg 56 which shows a mounting bracket welded to the bottom edge of the axle tube.

RonD2 · Post by **RonD2** » Wed Aug 07, 2019 10:24 pm

Thanks Wes, that nails it for me. I'm especially glad to know I don't have a MB Dana 25! Thanks!

But have to ask: the metal fitting end of your flex hose coming out of the top of the tee looks extremely long, at least compared to my store-bought hose. My imagination?

Post by **wesk** » Wed Aug 07, 2019 10:50 pm

Yes, it is awful long!

My Blue USAF M38 is not a Trailer Queen. I built her as close to original while using modern parts and solutions. That line fit and the fitting for some reason was very odd but I used it anyway.

RonD2 · Post by **RonD2** » Sat Aug 10, 2019 8:54 pm

While I'm on the subject of the front brake tee, I happened to notice that the fluid passage holes in my original tee where the hard lines mate are smaller in diameter than an original NOS tee from a sealed package that I compared it with. In the photo below, the new tee is on the left, original tee on the right.

Is the steel nut and line designed to deform the softer brass seat where the double-flare mates --- and also reduce its diameter like this? Or did the last guy who assembled it over-crank it and the tee is damaged to the point it should be replaced? Or perhaps it's just two different manufacturers?

I notice the exact same thing on my rear tee as well (comparing it to a new tee). So I'm thinking this might be normal, and nothing to be concerned about?

I have new tee's if necessary. My rookie mechanic question: if the original tee will seal with new lines, should I use it --- or replace it anyway? In other words, when installing new lines, use a new tee?

4x4M38 · Post by **4x4M38** » Sat Aug 10, 2019 9:23 pm

Ron,
To me the one on the right looks damaged.

If it were me, I’d use the one on the left.

Just my two cents.

Post by **wesk** » Sat Aug 10, 2019 11:11 pm

When the steel brake tube flare leaves an imprint like you have on the cone in your old fitting I will reuse the fitting if the same tube is being reused. If you are using new tubes use the new "T".

RonD2 · Post by **RonD2** » Sun Aug 11, 2019 8:54 am

Thanks, and Wilco.

I also noted that neither of my tee's had copper washers (G740-7372834, WO-637426) sealing the flex line connections. Always one more thing to buy.

Wes, I see that your hard lines aren't painted. I've read in this and other forums enough to know that they left the factory with paint, but that some folks prefer no paint. I like the idea of paint for corrosion control, but also that if unpainted their condition can be readily seen. While mine will seldom if ever get wet and muddy, can anybody relay their experience with these modern steel lines? Do they rust in a heartbeat? Maybe a coat of clear on them instead of primer and paint?

RonD2 · Post by **RonD2** » Thu Aug 15, 2019 8:11 pm

Ok, primer and paint it is!

Post by **wesk** » Thu Aug 15, 2019 10:47 pm

Some new steel tubing and ready made lines have corrosion protection applied. Others I would probably clear coat.