Where is this oil coming from?

[HOWEY]

I have an unusual oil leak in my transfer box output shaft.
The seal at the box is fine but im losing oil around the u joint area??, it throws out oil under the floor at that spot
See the pic for a better explanation.
Any ideas guys??

 

[73m819]

The plug in the slip yoke is missing/leaking, yep from a blown up pic, I can see the splines IN the yoke which means NO plug, find the correct size freeze pulg, that will fix that

 

[HOWEY]

plug the leak ?

The plug in the slip yoke is missing/leaking, yep from a blown up pic, I can see the splines IN the yoke which means NO plug, find the correct size freeze pulg, that will fix that

Can these plugs be bought separate to the yoke and will the driveshaft have to come off for installation??

 

[ODdave]

I dont think your gonna find a core plug to fit it as the plug for the yoke is a flat disk. your going to have better luck picking up another yoke. You have to pull the yoke off anyway to fix it.

 

[doghead]

I bet a standard sized freeze plug will work.

 

[73m819]

I have used freeze plugs, get a tight fit, then use a big round punch to set the plug just like doing a freeze plug on a motor, if you can not find a standard plug, try a metric one

Yes on dropping the drive shaft, and the u-joint needs to come-apart, this all has to be done no matter if you replace the yoke or repair it

 

[ODdave]

you have used freeze plugs on a cucv driveshaft? I ask because the machined recess is only about 3/16 deep

 

[73m819]

Not on a cucv, but on other auto yokes, 3/16 is plenty for a freeze plug, should still give a bit of a exposed shoulder after the install

If you have the yoke plug in your hand, it looks just like a freeze plug,

 

[ODdave]

no, it dosnt. Looks like a washer with out a hole.

 

[1956_4x4]

no, it dosnt. Looks like a washer with out a hole.

There are freeze plugs like that. They have a slight dish to them.

Smitty

 

[ODdave]

well mabye im wrong but I personaly have never seen a core plug with out a shoulder. And it is much less than 3/16. I will take a pick of the yoke as well if anyone wants. OP, the od on the plug is 1.496 fwiw

 

[73m819]

some popped out freeze plugs look like a washer without a hole, all this does not matter, if the fix works, it works, a cheaper try then buying a new yoke, things are a-part, so much is not lost
the yoke plug is installed the same as a freeze plug, a slight curve, then flattened for a compressed fit, a machine flatting will look flat, YOU ALL do what you want, made my suggestion for a cheap fix

 

[ODdave]

Im not bashing, Just hate to see him go on a wild goose chase. there is not enough room for a shouldered plug.

What would work is if he where to take a core plug (as you mentioned) and cut the shoulder off and ground/ machined it to the spec I mesured off of mine (Yes I removed it from the exacte yoke he needs). The bevil on the plug would alow him to install it and help it stay when its pressed flat.

You could probably get a yoke at a junckyard for less than $20 though..... HeII id sell one for $20 but shipping is like $13

 

[jag7720]

This happened to me too... and since you need to take the joints apart to "fix" it I found a new replacement for about $30or $40 and put that on and new joints at the same time.

 

[idM1028]

I've never really liked how the joints on these trucks are permanently sealed and ungreasable. I've heard of guys drilling holes in permanently sealed joints and installing a grease fitting, but I'd rather not take the chance of screwing something up. I'd rather just spend $30 or $40 on a part that's made to be greased in the first place. Greaseable 1410 U-joints would be nice. Just my

 

[1956_4x4]

well mabye im wrong but I personaly have never seen a core plug with out a shoulder. And it is much less than 3/16. I will take a pick of the yoke as well if anyone wants. OP, the od on the plug is 1.496 fwiw

Try doing a Google search on "fllat freeze plug". You should find them under a couple different names. I've been pulling wrenches for over 40 years and although I don't run into them very often, they are out there. Try Napa for a source.

I don't think it would be a wild goose chase if a little research is done.

Smitty

 

[ODdave]

Try doing a Google search on "fllat freeze plug". You should find them under a couple different names. I've been pulling wrenches for over 40 years and although I don't run into them very often, they are out there. Try Napa for a source.

I don't think it would be a wild goose chase if a little research is done.

Smitty

Have at it, I'd just buy a new one.

 

[1956_4x4]

I have an unusual oil leak in my transfer box output shaft.
The seal at the box is fine but im losing oil around the u joint area??, it throws out oil under the floor at that spot
See the pic for a better explanation.
Any ideas guys??

PM sent with a source and part number. It should help get you going in the right direction. Since OD measured the plug at 1.496", I'd go with the 1.5" plug. I can't see it costing more than a dollar for the plug, but I'd go ahead and change the u-joint since you will have it apart.

Hope this helps.

Smitty

 

[Barrman]

The LU4 winch used on M37 and M715 trucks uses one of those curved dish type plugs to seal the bottom of the selector shaft. Just like on the yoke. Set in the the hole and whack it with a hammer. The last one I replaced maybe cost a dollar.