Rear Pinion Seal Leaking - MagHytec - Diesel Forum

Bill Tifft · 09-30-2003, 05:03 PM

At 50k my rear differential pinon seal started leaking as have some of the other Ex's according to various posts. I installed the MagHytec cover at 30k and set the fluid level using the dipstick that comes as part of the new cover. The shop I had replace the seal mentioned that the fluid level was a little high which may have caused the seal to begin leaking prematurely but that typically in the 50-70k range they all begin to wear and leak. They said the best way to assure the proper level is to use the factory check plug on the side of the diff. If you have the MagHytec cover you may want to double check the fluid level using the factory check plug to get it set right. All is well now with the new seal.

pabrannan · 09-30-2003, 05:12 PM

Bill, did you watch them do the job?? Would like to know how they re-assembled?? I had mime done and it was done wrong the first time and only torqued to 165 ft/lb the second time. There has been a lot of discussion not too long ago about this and it is still fuzzy to me.

Thanks,

Paul B

Bill Tifft · 09-30-2003, 06:50 PM

Paul,

No I did not watch them but I took it to a shop here in San Diego called Pro Gear. All they do is work on 4x4's gearing, transfer cases, differentials, etc. The shop foreman stepped me through the process of getting the proper crush ring and seal. Measuring the torque it took to get the old nut off and then re-tightening the new nut and crush ring to the exact spec that they took the old one off. There is an art to setting the pinion and pinion bearing pre-tension so that the ring and pinon gear set mesh properly and last for many miles without problems. Ford wanted twice the price and to have those guys work on it. Anytime a Ford tech touches my rig I get real nervous. This shop does work on these same seals 2-3 times a week on the Super Duty trucks. If they weren't doing it right they wouldn't be in business. I feel confident that I won't have any future problems.

-Bill-

pabrannan · 09-30-2003, 09:06 PM

Your process is exactly how my personal mech. explained it to me. Trouble is that two Ford dealers have done mine and have not got it right yet. Even though I can get it done for free, under their 12k miles,12 month warranty, here at home I am still leery. I just might pay the local rear end only shop, I have used before, to reset it. As you indicated it is an art, experience, and knowledge to do it right.

Thanks for the response,

Paul B

orion7144 · 10-01-2003, 06:48 AM

I just had mine done at about 48K by the Ford dealer (out of warranty). Seems to be holding up after a 2k miles. Did either of you notice a reduction in your gas milage when the fluid was low?

pabrannan · 10-01-2003, 05:27 PM

My fluid was never low. This happened on vacation and I noticed black spots on the front of the TT when I stopped for fuel. Looked under and saw minor splattering on the wheels. When the mech. checked the fluid after re-installation it was right where it should be. I watched the entire operation. So all in all no change in fuel mileage. Average MPG on 6.5k trip from Florida to Grand Canyon and back was a solid 12 mph! I thought this was good, seeing temps were from 100* to 106* most of the time, 70 to 75 towing and solo. If I remember low was 10 and high was about 17 mph.

Sorry for the long reply,

Paul B