Hey guys, where is the breather on my 93 rear end? (dana 70). i looked for the thing in the sticky, but my truck does not have that. Also, what would cause play in the pinion? you can turn the pinion a little with the truck in park. its a 93 4x4 in my sig.
thanks.

 

Try and turn the drive shaft when in neutral, the play you are filling could be the tranny........

If there is a lot, it could be badly worn spider gears, or bigger problems

there should be some rotation play in it............If its up and down play, that could be bad..........Is the oil full?



Flash

 

Your vent tube should be on top of the rearend "pumpkin". Just trace all lines and fittings. You should see the end of it attached to the inside frame rail. All diffs come with a vent of some type. It is very important that the differential has a clear path to vent when the fluid gets warm and pressurizes. Many times a clogged vent tube will cause fluid pressure to build up and push out of the pinion seal or diff cover gasket. Remember: the fluid will find the path of least resistance when overpressurization occurs. As for the pinion movement.........there is allowable "backlash" for lubrication of the gears. You will only know exactly by finding the specification and measuring. If it is super-sloppy.........you might have further problems and should investigate. Hope this helps!

 

If you can get 1/4 turn on the pinion and the rear doesn't howl, then it's a worn cross pin (open diff) or worn clutches (limited slip).

 

Ok, well i am convinced my rear end does not have a breather. tell me where it is, or where it should be and how i can install it.
thanks.

 

IIRC is should be on the bolt that holds down the brake line union, with the hose coming off of it. The one that is not connected to the housing in your 2nd pic. Perhaps whoever lifted your truck disconnected it to keep some slack in the brake lines, and the hole filled with gunk? You should not have the vent hose like that without somewhere to put it. It was there at one time.

 

^^ Agreed. Whoever did that . . . . . shouldn't anymore. I'd be VERY concerned about the brake lines fracturing.

That big fat line taking off to the left of the second image is the OEM vent tube.

 

Your rear "may" not be vented anymore. That's a hollow bolt with a nipple for the vent tube that holds the brake line splitter block on top of the axle housing.

If the guy replaced a solid bolt in the hole after he took it off to re-seal the hole, then it's not vented and you'd probably be seeing leakage. But considering the whole approach and the fact you did not say anything about leaking, I'll bet it is vented - with an OPEN HOLE!

...Which has been collecting dirt all this time and may explain the loose pinion. Bearings are probably shot. Better get the cover off, inspect and change the gear oil, at the very least. Just put a longer piece of tubing on the vent after you reinstall it correctly, of course.

 

From the look of the image, the hole's missing or stopped up to the point it's not to be seen.



Is that the original axle housing?

Looking at the first image, one can see the input/pinion seal is leaking. I see a "Dark Ring" around the inside of that far rim. The fill bung is leaking.





.

 

Here is the solution:


https://www.dieseltruckresource.com/...d.php?t=153307


Guaranteed to work on any vehicle.


As for your situation, I am gonna say that the vent-bolt just rotted off and allowed the brake-union to move up there.

I spot several a day in that shape, the owner being none the wiser.

 

Yes, i know the rear pinion seal is leaking. I just couldnt figure out why my axle wasnt vented. where my abs junk bolts down,there is a bolt that holds that clamp down, its just a bolt, no through barbed fitting. does this bolt go through to the pumpkin? does anyone know the thread size to this? if it goes through to the pumpkin, could i remove that bolt and get a barbed fitting and just run a 3/8" line up to the bed?
thanks.

 

Your vent is there, right where the one in BC847s picture shows it; it is just rusted solid across and well camoflauged.

 

OK, i found it under a lot of grease, and it was covered in dirt, no plug or anything in the hole!! does anyone know what size breather bolt would fit in that hole, so i could just run the breather from that hole? does anyone know what size thread this little hole is?

 

I just put new side and spider gears in my truck over the week end.
theres was not a 1/4 of a turn of play but a lot of play just the same.
Cut the play in half.

For any body that is planning on this chore, the spider gears will NOT come out of the carrier with out removing the carrier and then the ring gear.



Flash.

 

Just as I suspected. I hate it when edit people do stuff like that. Polly just took it out when the lift stretched it and left it.

Dunno exactly what size/thread bolt, but you gotta fix that before doing any more damage.

Try Randy's Ring and Pinion. They have virtually every rear-associated part ever made.