Front Diff. Leak

[Patch101]

Looks like its coming right off the bottom of the front diff.

I put 70lbs on the bolts to make see if I could stop the leak, but
it didn't seem to help (hard to tell where its comming from because of that huge lip) although I did notice the lowest bolt just spun.

So I guessing that its because of the loose bolt. Any recommendations
or just a matter of unbolting everything and putting on a new gasket?
I've been putting it off but winters coming 8)

I'll probably have to replace my Rad (just noticed yesterday that it was starting to leak a little from the side, no noticeable crack, just from the seem) and Oil pan (I thought that was from the plug, but after cleaning it up I saw that someone before me got the idea to use liquid metal to seal a crack. Gah ....

 

[krugford]

If the front diff is leaking (or the rear for that matter), your only real option is to take the pig out, clean the mating surfaces and reseal. Torquing the bolts tighter won't seal the leak. It will strip the threads pretty effectively though, as you found out. If you want that bolt to hold any kind of load, you're going to have to see if you can put in a helicoil in there. I'm not sure how much extra material is there to do such a repair, but if there's not enough, you might have to replace the housing.

 

[Patch101]

Yah, although I think that bolt was already done, I didn't get any tension from it when I was seeing if I turned the bolts. I think right now the plan is to go back for my 4th year of trade school, park the truck, then maybe fill the diff up with some gear oil and stop leak and get through the winter months in Jan and Feb, and then see about trying to tear it apart in the spring. Don't know about attempting to tear it apart in Nov. when I'm broke and in school.

 

[4x4junkie]

Yeah, you can put a helicoil in it no problem (infact, drilling out ALL the holes and installing helicoils would be one of the best things you can do for it (also get some ROUND bolts (or studs) for it, too).

 

[Wicked_Sludge]

ive never seen stop leak for gear oil....and if it exists, i dont forsee it working. gear oil is already about as thick as oil gets.

even though the diff is leaking, if you check the level, you'll probably discover its not that low. it takes a pretty substantial hole to let gear oil escape with any enthusiasm.

 

[Ranger5.0]

ya, theres plenty of meat in the diff housing to drill'em out, heli coil them and use REAL bolts. The ones in there from factory are of the cut yer own thread varity. They are bland holes on the assembly line, so they use the self tapper's during assembly at the factory. It takes a bit of time but driling them out and using heli coils is a great plan.

 

[MAKG]

Self-tapping bolts are also a really nice way to completely bugger threads by cross-threading.

AFAIK, there is no gasket. Clean it up really well with a gasket scraper followed by brake cleaner, then glue it on with ultra-black RTV. RTV works well sealing gearboxes. It doesn't work as well on crankcases (though some applications DO use it on oil pans).

This is a PITA, but it's the only way you'll seal the leak.

 

[Patch101]

thx guys!

 

[sebastian323]

My front differential has a leak on my 96 4x4. It is not leaking from the front driveshaft input seal, so i assume that I will need to drop the front diff to service it. I also need to change the coil springs on my truck. Does dropping the front differential involve dissasembling the front suspension?

 

[sgtsandman]

My front differential has a leak on my 96 4x4. It is not leaking from the front driveshaft input seal, so i assume that I will need to drop the front diff to service it. I also need to change the coil springs on my truck. Does dropping the front differential involve dissasembling the front suspension?

On a 1996? Shouldn't the differential be exposed already on those? If it's a Twin Beam like I think it is, the cover should be down where you can work on it. It's only the Dana 35 SLA that you have to worry about dropping the axle to be able to get at the cover and it's bolts.

 

[Curious Hound]

The D35 ttb does not have a cover. The axle beam is the cover. I don't remember how much needs to be disassembled to remove the diff housing from the beam. But it does not require a full disassembly of the whole front suspension.

 

[sebastian323]

The D35 ttb does not have a cover. The axle beam is the cover. I don't remember how much needs to be disassembled to remove the diff housing from the beam. But it does not require a full disassembly of the whole front suspension.

This sounds about right. I imagine at minimum I must remove the axles, which it seems may be easier to pull while the shocks and coil springs are removed.

 

[Curious Hound]

The axle shafts must be pulled. I think the axle beams can stay mounted. It's a good time to do the c-clip delete modification to make future maintenance and repairs easier. There is info in the tech library for that.

 

[sebastian323]

The axle shafts must be pulled. I think the axle beams can stay mounted. It's a good time to do the c-clip delete modification to make future maintenance and repairs easier. There is info in the tech library for that.

I looked into the c-clip delete and it looks like I need a special spring to replace the c-clips. Any idea where I can buy this one ?

 

[Curious Hound]

A good lawn and garden parts store. It's a spring for a strung trimmer head. I think the info is in the article in the tech library. I'll try to remember to see if I wrote down the info when I ordered mine.