ATTN Ford 8.8 Guys: Pinion Seal Replacement

[AlexTJ]

I noticed a funny noise coming from under the jeep so I look under it to find my 8.8's pinion leaking. How hard is it to replace the seal on these?

I also found a couple of my driveshaft/adapter bolts loose... Really hoping that didn't reek more havoc other than hurting the seal...

[crem]

same thing is happening to me. is the fluid like a milky grey color?

[80cj]

That's a crush sleeve pinion so you're supposed to check the pinion rotating torque with an in. lb. torque wrench befor you loosen and remove the old nut. When you replace the seal, use a new nut and preload the pinion to the previous reading plus 5 in. lbs.

[themonkeyman]

Since it sounds like you've lost a good amount of fluid (thus the noise I'm guessing) be sure to use Diff oil with the proper clutch-type LSD addative when you refill it if you have an LSD-equipped 8.8

[ecaps]

When the seal on my 8.8 went bad, when I drained the fluid it was a milky gray color. I guess from contamination?

As 80cj said, get the the torque inch/lbs readings before loosing the pinion nut. The other option is to mark the nut/bolt & write down the number of turns it takes to removed the nut.

I think the inch/lbs readings should be 8-14 inch/lbs if you're reusing the pinion bearings and 16-28 inch/lbs for new bearings.

When you go to replace the seal, I put a small amount of gray RTV on the back of it to help seal it to the housing and prevent leaks.

Also, if you're reusing the pinion nut, I usually put on a small amount of red loctite to help keep it from backing off.

FWIW, when I rebuilt my 8.8 I got new pinion nut and a crush sleeve elminator from summit. I bought new crush sleeves, but was never able to get them to "crush" and get the preload.

Ratech 1502 - Ratech Differential Pinion Nuts - Overview - SummitRacing.com - Pinion nut
Ratech 4105 - Ratech Pinion Bearing Spacers - Overview - SummitRacing.com - 8.8 crush sleeve elminator.

[AlexTJ]

Originally Posted by ecaps

When the seal on my 8.8 went bad, when I drained the fluid it was a milky gray color. I guess from contamination?

As 80cj said, get the the torque inch/lbs readings before loosing the pinion nut. The other option is to mark the nut/bolt & write down the number of turns it takes to removed the nut.

I think the inch/lbs readings should be 8-14 inch/lbs if you're reusing the pinion bearings and 16-28 inch/lbs for new bearings.

When you go to replace the seal, I put a small amount of gray RTV on the back of it to help seal it to the housing and prevent leaks.

Also, if you're reusing the pinion nut, I usually put on a small amount of red loctite to help keep it from backing off.

FWIW, when I rebuilt my 8.8 I got new pinion nut and a crush sleeve elminator from summit. I bought new crush sleeves, but was never able to get them to "crush" and get the preload.

Ratech 1502 - Ratech Differential Pinion Nuts - Overview - SummitRacing.com - Pinion nut
Ratech 4105 - Ratech Pinion Bearing Spacers - Overview - SummitRacing.com - 8.8 crush sleeve elminator.

The noise was probably more the loose driveshaft if anything. I found almost all the bolts loose. (now using locktite)

I marked it and went slightly past my mark since the pinion had some play when i lined them back up.

Just kinda guessed since I don't have an in*lb torque wrench and I couldn't even use my ft*lb because my brother who brought me the tools (I'm at college 45 min from home) forgot the right adapter.

Its not leaking any more and there is no play in it either. I just hope I didn't get it too tight.

[themonkeyman]

Originally Posted by AlexTJ

The noise was probably more the loose driveshaft if anything. I found almost all the bolts loose. (now using locktite)

I marked it and went slightly past my mark since the pinion had some play when i lined them back up.

Just kinda guessed since I don't have an in*lb torque wrench and I couldn't even use my ft*lb because my brother who brought me the tools (I'm at college 45 min from home) forgot the right adapter.

Its not leaking any more and there is no play in it either. I just hope I didn't get it too tight.

Eh, I wouldn't blame your bro too much, ft-lbs would have been useless, if it did read on the pinion resistance, you'd have much larger problems than a bad seal. I would definitely check the fluid level, since it was leaking.

Good luck, keep us posted.