Leaking Rear End

[USMC205]

I’ve got a leaking rear end and I’m not sure exactly what the leaking part is called.  I’ve attached a picture.  It’s not coming from the pinion seal but behind that.  Is this the carrier or is the carrier the whole top assembly that drops down into the housing? Where it’s leaking looks relatively simple, drop drive shaft undo bolts and it should pull forward. It seems those two empty holes are to out a bolt in to separate the parts?  Also when I had it cleaned it looked like a drop of oil came out of the hole on the bottom.  Is this possible?  I’ve had a tech tell me that since I have 4.44 gears it will not pull all the way out, just an inch or two and just enough room to clean and reseal.  I’ve also read that I need to take the inspection plate off the side in order to get to two bolts.  I think I may have a little bit of both repairs mixed up in my head.  If anyone has experience I this I would welcome a text or even a phone call if you have time.  It’s an 01 RD688 Dump.  Thanks.

[Mack Technician]

Nail down exactly where the leak is coming from. If its the pinion housing in the center of the picture that's a pretty easy fix. Most likely, usually, it is coming from the mounting surface of axle banjo-to-differential. The best thing to do is pull the top breather and hook up an air pressure regulator. Add 3-4PSI to the diff and spray (soapy water) the suspicious areas.

[USMC205]

1 hour ago, Mack Technician said:

Nail down exactly where the leak is coming from. If its the pinion housing in the center of the picture that's a pretty easy fix. Most likely, usually, it is coming from the mounting surface of axle banjo-to-differential. The best thing to do is pull the top breather and hook up an air pressure regulator. Add 3-4PSI to the diff and spray (soapy water) the suspicious areas.

Yes sir it looks like it’s coming from the part that has the extra holes to pull it apart?  What’s it called and is it as simple as pulling it apart and sealing it or is there more to it?  

[Mack Technician]

39 minutes ago, USMC205 said:

Yes sir it looks like it’s coming from the part that has the extra holes to pull it apart?  What’s it called and is it as simple as pulling it apart and sealing it or is there more to it?  

Drain the top shelf using drain plug on opposite side (rear facing) of this housing. Pull the six 12pt bolts and whack the housing a few times with a large dead blow. The housing will have shins for seals. Measure the shims with a micrometer. Purchase new. Apply a spray sealant on shims and install. I use to use shellac spray. I’ve seen high tack used. I prefer shellac. 

The empty holes are for jack screws. You likely won’t need them. Not to mention there may be no good threads left in Jack screw holes. 

[Mack Technician]

You can download this differential manual for free off Mack emedia.

[Vladislav]

2 hours ago, Mack Technician said:

Drain the top shelf using drain plug on opposite side (rear facing) of this housing. Pull the six 12pt bolts and whack the housing a few times with a large dead blow. The housing will have shins for seals. Measure the shims with a micrometer. Purchase new. Apply a spray sealant on shims and install. I use to use shellac spray. I’ve seen high tack used. I prefer shellac. 

The empty holes are for jack screws. You likely won’t need them. Not to mention there may be no good threads left in Jack screw holes. 

Spray sealant? One really good idea. And bad thing I'm not sure that's a stuff I could easily fing in my neck of the woods.

When I went through that step assembling a carrier I applied common sealer from a tube and sure got some outtashapeness of contact pattern on the teeth.