How To Install Mustang Differential Cover

Please note for the Fox Body and SN95 owners, depending on how low the car is or suspension setup we strongly recommend that you verify clearance of all components (especially the spare tire well). For S197 owners this is a good time to make sure your vehicle has functioning bump stops. Also, before installation make sure that you can loosen and remove the factory fill plug on the front of the housing.

TOOLS REQUIRED:

• Socket Set
• 3/8" Drive Torque Wrench
• Shop Towels
• Quality Brake Clean
• Correct Weight & Amount Of Gear Fluid

REMOVAL/INSTALL STEPS

1. Safely support vehicle with jack stands or a lift.



2. Loosen and remove all of the differential cover bolts EXCEPT for the top one.



3. Position the drain pan underneath the rear end.



4. Use a flat head to separate the cover from the housing and allow some of the fluid to drain out.



5. Now you can loosen and remove the top bolt (make sure you hold the cover with your free hand to avoid it from falling).



6. Set the cover aside and use towels to clean up any fluid at the bottom of the housing.



7. Before cleaning the remaining surface, you will need to cover the rear end components with some towels.



8. Use a gasket scraper and remove the old RTV silicone.



9. With the old silicone removed, use a scuff pad to clean up the surface.



10. Wipe the surface with a towel and quality brake clean and run your finger over the surface to ensure that it is smooth.



11. Now that the surface is smooth, flush out the bolt holes with brake cleaner or compressed air.



12. Remove the towels that cover the rear end components and wipe the surface one more time just to make sure it’s clean.



13. If your aftermarket cover has bearing cap supports, a few extra steps are going to be required.



14. Loosen and remove both of the jam nuts.



15. Back the load bolts all of the way out until they bottom out on the underside of the cover.



16. Now you can take the diff cover and align with the Lube Locker gasket.



17. The 2 notches on the gasket will align with the notches at the bottom of the rear end (If you are going to be using RTV, apply a thin bead of it to the diff and make sure you go towards the inside of the bolt hole instead of the outside).



18. Slide a bolt through the top hole and position the cover on to the rear end. Thread the top bolt by hand just a few turns to hold in place.



19. Next, we recommend threading the bottom bolt in, then will install the rest of the bolts working in a clockwise pattern.



20. Run all of the bolts down by hand, then torque to 20-25 lb-ft in order of the pictures shown.












21. Apply a Tephlon based thread sealer to the threads on the load bolts (you don’t have to apply to all thread but we recommend at least 4 threads from the face of the cover).



22. Tighten the load bolts by hand until they touch the bearing cap.



23. Torque bolts to 5 lb-ft.



24. Reinstall the jam nuts and either hand tighten or torque to 10 lb-ft.



25. Now we can fill the housing by removing the factory fill plug along with the fill plug in the cover if it has one.




26. We currently sell Royal Purple fluid with the friction modifier already added to it but provide a small bottle as well.



27. Cut the tip off of the fluid bottle to accommodate a piece of clear hose around 6” in length.



28. Begin filling the housing with fluid and once the first bottle is empty, switch to using the second one. Fill until the fluid starts to seep from the factory fill plug or if you fill a quart and half into a 7.5 rear end or 2 quarts into an 8.8 rear end.



29. Reinstall and retighten the factory fill plug (for added safety you can add Teflon based sealer to the fill plug in the cover and retighten as well).



30. Use this time to check over your work and you are good to go!




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