Teal96XJ

Alright well im trying to fix a leak i have coming from the front diff. but i need to find out what it's called 1st so i can get the part......The leak is coming right where the front driveshaft goes into the diff. does anybody know what the part is called the leak is getting pretty bad now so any help would be great.......

muddeprived

Front dana 30 Pinion seal.

Before you go buy a seal, remove the driveshaft (four bolts, 8mm i think) and try to wiggle the yoke (the part where the driveshaft bolts onto). See if there's any play or clunking. If so, that means your pinion bearing could be going as well. Usually the pinion seal just starts leaking cuz of mud and stuff but sometimes the pinion bearing goes and then it allows plays which wears out the pinion seal. I'm betting it's just the seal though.

One other thing FYI, this is not just a "take off and replace" type of repair. You have to find the torque specs for that big nut that's on there now and make sure you torque it the same +5 or so i believe. So if that nut was on at 180 ft lbs then you reinstall it at 185. I think this is the way but let someone else chime in to be sure.

Teal96XJ

Alright sounds good how hard is it to do?!?!?

And i have a tourqe wrench so that's no problem.......

muddeprived

OK I may have been a little wrong above. I was thinking the dana 30 had a crush sleeve like my dana 35 did. This is what I found on NAXJA:

The D30 doesn't use crush sleeve just shims and torque.
Since you are not replacing the pinion or its shims, here is what the manual has to say.
REMOVAL
1) Raise and support the vehicle.
(2) Remove wheel and tire assemblies.
(3) Mark the propeller shaft yoke and pinion yoke for installation alignment reference.
(4) Remove the propeller shaft from the yoke.
(5) Remove the pinion yoke nut and washer. Use Remover C—452 and Wrench C—3281 to remove the pinion yoke (Fig. 5).
(6) Mark the positions of the yoke and pinion gear for installation alignment reference.
(7) Use Remover 7794A and slide hammer to remove the pinion gear seal (Fig. 6).

INSTALLATION
(1) Apply a light coating of gear lubricant on the lip of pinion seal. Install seal with Installer D—163 and Handle C—4171 (Fig. 7).
(2) Align the reference marks and install yoke on the pinion gear with Installer W—162—D.
(3) Install a new pinion nut on pinion shaft, lighten the nut to 217—352 N.m (160—260 ft. lbs.).
(4) Align the installation reference marks and attach the propeller shaft to the yoke.

I don't think you really have to remove the tires and wheels to do it. It'll be easier to get the nut off if the tires are still on and the jeep is on the ground cuz the pinion will not rotate.

MasterShakeXJ

i'm terrible with conversions but i think the bolts are 5/16, might be the exact same as 8mm though haha.

i think the hardest part is getting the bolt off.

Teal96XJ

That makes it sound like a not so easy job lol......

muddeprived

Yeah it does doesn't it but it's pretty simple.

Remove four bolts holding driveshaft on yoke.
Make reference marks to install everything back the same way.
Remove big nut.
Remove washer.
Tap out the yoke.
Use flathead or other tool to remove seal.
Coat outer edge of seal with rtv and install.
Reinstall everything else.

That's about it.

Found this:

http://www.jeepingsingles.net/tech/pinionseal.asp


But it says there is a crush sleeve. Some say no, some say yes. Now i'm confused.

muddeprived

I checked my haynes manual.

Mark the relationship of the pinion shaft to the yoke. Remove the nut. Remove yoke (with puller if neccessary). Carefully pry out the old seal with a screwdriver or pry bar. Be careful not to damage the splines or seal surface.

Lubricate new seal lip with multi-purpose grease or diff. lube and carefully install.

Clean the sealing lip contact surface (where the seal touches the yoke). Apply a thin coat of multi-purpose grease to the seal contact surface and shaft splines and lightly tap the yoke into position, making sure your reference marks line up. Install washer and nut and tighten to specified torque. My manual does not state what the dana 30 torque specs are though. It shows how to find that for a dana 35 but nothing on the 30.

Teal96XJ

Well thanks man im goin to jump on it later this week since it keep's raining over here.....