I need some help troubleshooting here. I'll try to keep this short. So far my front diff has been leaking anytime I drive it, looks like it is leaking around the seal, will try to gets pics this afternoon and post. But it only leaks whenever I have the propshaft in. I drove around for almost 2 weeks with the shaft out and no leaking anywhere. I put the prop shaft back in and drive 20 minutes and my undercarriage is coated with gear oil. I am about to go pull the propshaft again to make sure it only leaks with the shaft in. Just wondering if anyone has encountered this and how involved is it to pull and replace front diff. this truck is now my DD so I can't have it down for to long. How much is a new diff if I need one?
front diff leaking....now with pic!!!!!
- Thread starter sy112
- Start date
Alright, after closer inspection I don't think it's the input seal, cause that is where the propshaft bolts to the diff right. It appears to be leaking from where the drivers axle mounts to the diff, as you can see in pic. It is leaking now with or without the propshaft in. Any ideas?
ItsMyTy
Life is beter at 25 PSI
yep that axle seal is gone
it's a bit of a pain in the ass... only because the cv halfshaft won't just come loose and get out of the way easily. you gotta take the upper ball joint loose to get enough clearance to move the cv halfshaft enough to get the axle out of the diff and install the new axle seal
pretty common problem on the s-series
it's a bit of a pain in the ass... only because the cv halfshaft won't just come loose and get out of the way easily. you gotta take the upper ball joint loose to get enough clearance to move the cv halfshaft enough to get the axle out of the diff and install the new axle seal
pretty common problem on the s-series
ericguy320
Stupid Member
:roll:sy112 said:
Lynn D. Brown
New member
OK, mine is also leaking in the same location. But another Q is, what do U use to seal it ? There is no gasket ! The book says to use some special Loctite Anaerobic flexible sealer. Well Loctite has been bought out, and the old part number 4 the sealer is no good anymore. So, I found something that is similar at NAPA, but I had to order it.
I put this goop on, but then when I had some guy in his garage install the pinion seal and preload the pinion bearing. ($40. - what a bargain that was !) However, I think he disturbed that seal and now the SOB leaks in the car. The sealer that was in there before all of this looked like a thick layer of red silicone, and I think it was sealing fine.
What did U use, John ?
I think U can move the Driver CV axle forward and out of the way, but ya gotta loosen the shock at the bottom and disconnect the Inner tie rod and center rod. I'm not crazy about doing that.
I put this goop on, but then when I had some guy in his garage install the pinion seal and preload the pinion bearing. ($40. - what a bargain that was !) However, I think he disturbed that seal and now the SOB leaks in the car. The sealer that was in there before all of this looked like a thick layer of red silicone, and I think it was sealing fine.
What did U use, John ?
I think U can move the Driver CV axle forward and out of the way, but ya gotta loosen the shock at the bottom and disconnect the Inner tie rod and center rod. I'm not crazy about doing that.
it's not that hard to remove the cv shafts and replace the seals.
you dont have to remove balljoints. just remove the outer tie rod bolt, the big nut on the end of cv shaft, the inner cv bolts, and the lower shock bolt.
then turn the spindle so that the forward area is opened up. push up on the shock, then move the inner end of the cv shaft forward until it is clear. then just slide out the other end.
then pull out your diff drive flange. after that remove the seal plate on the diff. if your flange "wiggled" a lot before, you might want to replace the needle roller bearing that is just behind the seal.
and if you are that far, you might as well remove the diff. that way you can open it up and clean out the inside and reseal the case halves.
and here is a quote about anaerobic sealers:
you dont have to remove balljoints. just remove the outer tie rod bolt, the big nut on the end of cv shaft, the inner cv bolts, and the lower shock bolt.
then turn the spindle so that the forward area is opened up. push up on the shock, then move the inner end of the cv shaft forward until it is clear. then just slide out the other end.
then pull out your diff drive flange. after that remove the seal plate on the diff. if your flange "wiggled" a lot before, you might want to replace the needle roller bearing that is just behind the seal.
and if you are that far, you might as well remove the diff. that way you can open it up and clean out the inside and reseal the case halves.
and here is a quote about anaerobic sealers:
all right, did mine today, here is how I did it:
remove the tie rod from the steering knuckle
removed the lower shock bolt, moved the shock to the left
turn the wheel all the way to the right and set the tie rod up and out of the way as much as possible
removed cv joint bolts, there were 6, very tight and had loctite on them, used a breaker bar to get them off
moved cv joint to far left, just barely had enough room
removed axle, inspected
removed plate, mine was stuck very good, it was my seal and not the plate leaking, but you have to remove plate to get to seal
carefully taped out seal and replaced with part # nos12494 from Napa
removed all the old stuff, swear it was just RTV on there, orange in color, used brake cleaner to make sure all surface areas were clean
i just used high temp RTV (black) to reseal plate, and used blue loctite on all bolts going back on.
i went ahead and replaced all the cotter pins just cause they were in bad shape, and I hate used cotter pins
then just reassembled it all in reverse, did not take long maybe about 2 hours while bullshitting with friend. seems to be working great, no leaks as of yet.
hope this helps someone out
remove the tie rod from the steering knuckle
removed the lower shock bolt, moved the shock to the left
turn the wheel all the way to the right and set the tie rod up and out of the way as much as possible
removed cv joint bolts, there were 6, very tight and had loctite on them, used a breaker bar to get them off
moved cv joint to far left, just barely had enough room
removed axle, inspected
removed plate, mine was stuck very good, it was my seal and not the plate leaking, but you have to remove plate to get to seal
carefully taped out seal and replaced with part # nos12494 from Napa
removed all the old stuff, swear it was just RTV on there, orange in color, used brake cleaner to make sure all surface areas were clean
i just used high temp RTV (black) to reseal plate, and used blue loctite on all bolts going back on.
i went ahead and replaced all the cotter pins just cause they were in bad shape, and I hate used cotter pins
then just reassembled it all in reverse, did not take long maybe about 2 hours while bullshitting with friend. seems to be working great, no leaks as of yet.
hope this helps someone out
big gear head
axle builder
Re: front diff leaking....now with pic!!!!!
The red sealant is used between the case halves. The cover on the driver's side uses RTV sealant. When you put the cover back on you need to line up the cover so that the seal is centered with the bearing. This can be done by installing the axle before the bolts are tightened. I have not done this with the differential still installed in the truck, so I don't know if that is possible. If the seal is not lined up with the bearing then it will leak again. If you look inside the case with the side cover removed you will notice that there is a small hole at the top. This is the vent. Don't get RTV in this hole or you will have a lot of leaks. Use a small amount of sealant around the outside of the seal before you drive it in, and a little grease on the lip of the seal.
The red sealant is used between the case halves. The cover on the driver's side uses RTV sealant. When you put the cover back on you need to line up the cover so that the seal is centered with the bearing. This can be done by installing the axle before the bolts are tightened. I have not done this with the differential still installed in the truck, so I don't know if that is possible. If the seal is not lined up with the bearing then it will leak again. If you look inside the case with the side cover removed you will notice that there is a small hole at the top. This is the vent. Don't get RTV in this hole or you will have a lot of leaks. Use a small amount of sealant around the outside of the seal before you drive it in, and a little grease on the lip of the seal.