How to reduce diff slop, budget mod, '90 Infiniti Q45

[subtle_driver]

I got annoyed by the torn differential mounting bushings on the front of my 1990 Infinity Q45. So I decided to do a trick I used a few times in the past to eliminate the slop and still have some degree of vibration dampening. (this mod will work on the z32 300zx, s13 240sx, and s14 as well)



The key to make this work properly, is to make sure the inner diameter of the spacer-washer is at least 20mm. This is so it will clear the collar on the pressed in bushing that comes on the differential. IF you do not do this, you will risk damage to the bushing and you will have a lot of vibration.


SPECIAL MADE WASHER WITH 20mm inner diameter (make sure to test fit the washer before installing to make sure it slides freely past the front differential bushing collar):



All you have to do is remove the front differential bolts, 17mm, and install a special sized spacer-washer that is about 2 or 3 mm thick and the same outer diameter of the rubber washer.
OEM RUBBER WASHER (Keep this in place when installing):



SPECIAL MADE WASHER goes in next, under the OEM rubber washer:


Then install the OEM stock washer and nut, and tighten down. MAKE SURE THE WASHER IS CENTERED, or it may damage the bushing collar. This will sandwich the bushing together and eliminate the up and down slop, you are done!



One less thing that is flopping up and down in the drivetrain when you are accelerating (clutch kick, shift up, power-braking) and shifting down (shift lock, left foot braking).