I was having some hard shift issues on my 1994 f250 7.5L (2 wheel drive) so about 2 months ago I took off my rear diff cover to make sure everything still looked good. I was very impressed at how clean the fluid was and didn’t find a lot of shavings and none of the gears looked grooved. So I put the cover back on and filled it with LUCAS gear oil. (I am a big fan of Lucas products)
*Hard Shift issue resolved: F250 hard shift even after replacing transmission. (1994 F250 7.5L E40D) *Please Help - Page 3 - Ford Truck Enthusiasts Forums


But now it looks like I have fluid leaking out of the left tire hub assembly and my rear diff was a quart low.
Should the gear oil be making it to the tire hub? Is there a seal that I should replace in the hub?


I have also recently been getting a vibration from what feels like the rear end when I step on the gas to get up to speed (speedometer will shake when this happens). It seems like it is not doing it as bad since I added the quart of gear oil. I have also been smelling gear oil after driving for a while and walk around to the back of the truck.


I don’t know a whole lot about rear differentials or transmissions. So any help would be great


PS. I hope SUBFORD jumps on this thread he is a great resource and had helped me in the past.

 

Oh and i replaced the U-joints yesterday so the vibration is not coming from that. :-)

 

yes there is a seal at the end of the axle tubes

 

Yep replace the seal and you'll be good to go.

 

yes there is a seal at the end there, depending on wether you have a semi floating or full floating rearend will depend on how to go about changing the seal, if it is full floating it will have numerous bolts around the hub inside of the lugs (think of a school bus rearend) or a semi floating, it will 'look like' a f150 rearend. if semi floating, you have to take the diff cover off, take out the little retainer bolt ( mine is a 3/8ths head, and take out the big steel pin, from there push your axle in a little and there will be a c-clip to slide out then the axle can slide out of the tube, from there pull the old seal out ( its pressed in, i used the unconventional method of claw hammer, not proper, but if careful it works) and install the new one, reverse the disassembly for reinstall, if the little retainer bolt is broken you can pick one up at dealership cheap, i just picked one up for $1.61 after tax.. all these are going in what i just did on my f250, but it is a light duty, so yours may vary if its a heavy duty or full floating rearend

P.S. glad your trans issue is resolved good, just finished reading through your other thread

 

Sounds like you are in good hands. But they need to know what kind of rear end you have before they can help you much more.
I would dough that the vibration is caused by the rear end. If it was from the the rear end you should have the vibration at all times.

 

Does the photo below tell you if it's a semi floating or full floating? if not how do i tell<O</O
and is the seal at the differential or at the tire hub?<O</O
<O</O

Would it make more since for me to go to a junk yard and just pick up a new rear end? Found one for 68$ with a 55$ core so only 123$<O</O
<O</O

SUBFORD: If you don’t think it’s the rear end do you think it’s my transmishion?<O</O

 

That is a full floating rear end.
The seal is in the hub.
I could not say, you would need to put it up on jack stands and run it up while looking under it for the cause from the side. Maybe the drive shaft is in 180 out after the transmission R&R.

 

remove the 8 center bolts and you will be able to "slide" the axle out ( i say slide as a loose term because it may have to be tapped loose then pulled out) and from what my book is showing it is a big O-ring type seal right after the front plate of the axle, be careful and have a drip pan ready along with some extra gear oil, you will loose fluid, but on the bright side you can leave the tire on and pull the axle without jacking up the truck

on autozone.com the seal is for a DANA Spicer 60or 70 axle, 2 required ( 1 per side ) $13.99 each, dont go by the image it gives, it is not a accurate representation

 

The hub does have to come off to change the seal.
You will need a special socket to take the axle nut off.
If you jack the side you are working on higher then the other side you will lose less oil.
There will be some oil in the hub as you pull it off that will go on the ground.
It is a lot easier if you take the tire off first.

 

The seal is #8 in the diagram below:


/

 

Thanks all i will give this a try today. :-)

 

Well I am having a hard time finding the seal. I have tried both auto zone and schucks and neither are able to order the part. Any suggestions before I go to FORD and pay a lot of money for a 13$ part?

 

Try online. There are a bunch of good online parts vendors, like rockauto.com.

 

Ok called a guy at a different shucks (O’Rlies) and he was able to find me the seal for 25$ and he should have it today by 5:00 pm. Got to love knowing people at the parts store that know what the hell they are doing.