Rebuilding a rear end. Observations and thoughts

[RedVenom48]

This is going to be, more or less, some observations I made while performing a rebuild of a Ford 8.8 rear end. This was my first time doing so, even as a professional. I hope these thoughts and observations make any rebuild or gear swap you may attempt easier.

These are in no particular order.

Redline Heavy Shockproof oil is not for clutch style limited slip rear ends. It is an amazing fluid, especially for transfer cases, industrial lubrication and heavy duty rear ends WITHOUT clutch type limited slips. There was some residue left inside my rear end housing from the last fill. Even with about 100 miles on the Amsoil Severe Gear 75w-140 gear oil, there was still residue.

Solid Pinion Spacers are hard to set up, especially with no instructions! I ordered a Jegs Ford 8.8 9" solid pinion spacer kit. It came with a solid spacer, and about 5 shims. Even measuring the old crush collar and getting it to within a few thousandths of an inch, getting turning torque and pinion nut torque to spec was a challenge. My preload torque was ok, but the pinion nut was no where near the spec (140) it was supposed to be. I was fortunate that the Ford supplied pinion nut came with a copious amount of industrial thread locker. It held everything together till I got it on my lift today.

I ended up using the crush collar the unit is designed for and, without surprise I easily got over the minimum torque spec AND got to preload torque easily. Ill say a solid pinion spacer is great for a car making obscene amounts of power and track only. For a street strip car, crush collar is just fine.

Rebuild the LSD clutch packs if you can. Its a bit of a PITA to get the S-spring in, but after seeing what my clutches looked like, i was happy I rebuilt the diff. There are plenty of online guides, and its fairly straight up. I think the Shockproof wore the clutches faster than normal, and definitely prevented them from working normally. The new clutch kit comes with new shims. Use them as they are spec'ed for that particular set.

4.10s are the SHIZNIT for our cars! Golly, does it transform driving around. Even coming from 3.73s there is a difference. Im only 250 RPM higher than the 3.73s in 6th gear at 80 MPH. Its going to make 1-4 ROWDY. lol

The Ford Racing G2 cover may actually do something to help differential deflection under racing load. Wont know until I make a few hits at the track but its a beeefy cover and the preload posts look well engineered. I used a bead of RTV around the posts before I torqued them down. A thinwall 22mm socket is required to torque the lock nuts.

I recommend upgrading to the Moser Carrier bearing stud kit. Its actually an ARP stud kit and it looks EXTREMELY robust, especially compared to the factory bolts. I red locktited the studs into the housing, torquing to 10ft lbs. Standard 8.8" torque of 90-100 fts pounds on the nuts for the caps.

Any questions lemme know! Hope this was decently insightful.

 

[biminiLX]

This is going to be, more or less, some observations I made while performing a rebuild of a Ford 8.8 rear end. This was my first time doing so, even as a professional. I hope these thoughts and observations make any rebuild or gear swap you may attempt easier.

These are in no particular order.

Redline Heavy Shockproof oil is not for clutch style limited slip rear ends. It is an amazing fluid, especially for transfer cases, industrial lubrication and heavy duty rear ends WITHOUT clutch type limited slips. There was some residue left inside my rear end housing from the last fill. Even with about 100 miles on the Amsoil Severe Gear 75w-140 gear oil, there was still residue.

Solid Pinion Spacers are hard to set up, especially with no instructions! I ordered a Jegs Ford 8.8 9" solid pinion spacer kit. It came with a solid spacer, and about 5 shims. Even measuring the old crush collar and getting it to within a few thousandths of an inch, getting turning torque and pinion nut torque to spec was a challenge. My preload torque was ok, but the pinion nut was no where near the spec (140) it was supposed to be. I was fortunate that the Ford supplied pinion nut came with a copious amount of industrial thread locker. It held everything together till I got it on my lift today.

I ended up using the crush collar the unit is designed for and, without surprise I easily got over the minimum torque spec AND got to preload torque easily. Ill say a solid pinion spacer is great for a car making obscene amounts of power and track only. For a street strip car, crush collar is just fine.

Rebuild the LSD clutch packs if you can. Its a bit of a PITA to get the S-spring in, but after seeing what my clutches looked like, i was happy I rebuilt the diff. There are plenty of online guides, and its fairly straight up. I think the Shockproof wore the clutches faster than normal, and definitely prevented them from working normally. The new clutch kit comes with new shims. Use them as they are spec'ed for that particular set.

4.10s are the SHIZNIT for our cars! Golly, does it transform driving around. Even coming from 3.73s there is a difference. Im only 250 RPM higher than the 3.73s in 6th gear at 80 MPH. Its going to make 1-4 ROWDY. lol

The Ford Racing G2 cover may actually do something to help differential deflection under racing load. Wont know until I make a few hits at the track but its a beeefy cover and the preload posts look well engineered. I used a bead of RTV around the posts before I torqued them down. A thinwall 22mm socket is required to torque the lock nuts.

I recommend upgrading to the Moser Carrier bearing stud kit. Its actually an ARP stud kit and it looks EXTREMELY robust, especially compared to the factory bolts. I red locktited the studs into the housing, torquing to 10ft lbs. Standard 8.8" torque of 90-100 fts pounds on the nuts for the caps.

Any questions lemme know! Hope this was decently insightful.

Lots of great observations here.
I like the Shockproof oil, solid spacer, G2 cover, bearing stud kit and of course the 4.10s!
I'm in a '14 with the 2.66 first and 0.50 sixth, and I've never been given a negative review of the 4.10s for our cars, but yes, you's will be rowdy with the earlier 2.97 trans.
Great with a sticky tire launch though.
Only thing I think you're missing out on is some sort of support brace.
I know you'll be launching at the strip, so at minimum, bolt-in Swarr Bar.
Great post.
-J

 

[RedVenom48]

Good point. I do have a Swarr Axle brace installed in my car. I actually had to get it shortened by a shop when I was in San Diego. I had to have 1/4" removed from both ends to get it to fit my housing with the BMR LCA relo brackets.

It is a very good option to get on your car, the CHE brace being another. Welding the axle tubes it s good idea too, but the robustness of the external brace is a better option I think. The Axle tubes can still twist on a hard launch. A Swarr or CHE brace will provide the benefit of a welded tube but also offer anti axle twist protection as well. At the very least, it will prevent catastrophic damage on a Hero launch. If you have a ton of power and all the grip off the line and drop the clutch, that would do it. Its solid insurance.

 

[Robert M]

Solid Pinion Spacers are hard to set up, especially with no instructions! I ordered a Jegs Ford 8.8 9" solid pinion spacer kit. It came with a solid spacer, and about 5 shims. Even measuring the old crush collar and getting it to within a few thousandths of an inch, getting turning torque and pinion nut torque to spec was a challenge. My preload torque was ok, but the pinion nut was no where near the spec (140) it was supposed to be. I was fortunate that the Ford supplied pinion nut came with a copious amount of industrial thread locker. It held everything together till I got it on my lift today.

I ended up using the crush collar the unit is designed for and, without surprise I easily got over the minimum torque spec AND got to preload torque easily. Ill say a solid pinion spacer is great for a car making obscene amounts of power and track only. For a street strip car, crush collar is just fine.

I was with the guy who set up my 8.8 with a Strange spacer/shim kit replacing the oem crush sleeve. It took a couple of installs/removals with shims added or removed to dial in the gears to where they were before I installed the True-Trac, but overall the spacer/shim set up seemed to go smooth. The only reason I wanted that set up is because there may be a time in the future when I need to remove the pinion flange, maybe a leaking pinion seal? or something else? I wanted the ability to remove my pinion flange as many times as I choose and then torque it back in place at that preset thickness with a new nut and not worry about possibly further crushing the crush sleeve which would then change the gear settings and most likely require a complete start over on setting the gears up. Other than the option of removing my pinion flange multiple times without concern of a crush sleeve changing thickness on the next re-torque, a crush sleeve would have worked fine, but in most cases, they are one time use......unless a person really has a feel for the re-torque of the pinion nut and the crush sleeve collapse. <<I am not that person....



R

 

[gimmie11s]

Should take the time to weld the axle tubes if you have he rear end out. Especially if you have plans for bigger power down the road.

I did mine when I installed 3.73s and it's easy as pie with the axle pulled.

 

[RedVenom48]

Im going to, at some point in time, swap to Strange Engineering Big Ford 9" ends for my 8.8". They developed a bearing retainer bracket for 05-14 Mustangs to utilize GT rear brakes (07-12 GT500) and factory ABS. Should be very robust and produce zero leaks compared to the C-Clip eliminator kits alone. Likely upgrade to Strange 35 Spline axles too. Ill have the tubes welded then as one last measure of insurance.

Id still recommend a Swarr or CHE brace as mandatory if you drag race.