Ever wondered what those clunky or chattering noises are coming from the rear of your beloved S15? Hopefully it’s not your exhaust dragging on the ground but instead is the cries from your diff begging for some new fluids to bask in. Even though these noises are all too common in a mechanical type LSD, a fresh batch of fluids should quieten and smoothen her up a bit.
Being such a simple task to do it yourself at home, why wouldn’t you give it a go?
Tools required: ½” ratchet/breaker bar, Tom Thumb Pump (or similar)
Technical Difficulty: Easy
Profanity Level: Low
Duraiton: 30 mins or less
For this fluid change I’m trying out the Penrite 85W-140 Mineral Gear oil for my 2-way LSD, slightly thicker than previous LSD oils I’ve tried like the Penrite 80W-90, Nulon SAE90 and Castrol SAF-XA.
Step 1. Jack up the rear of your car and rest it on jack stands for safety.
Step 2. First things first, ensure you can access the fill bolt on the side of your diff housing. Proceed to unwind and remove the bolt if possible with the 1/2″ ratchet. If your exhaust proves to be an obstruction you will need to remove the diff back section to get clear access (what a pain).
Step 3. With your oil pan underneath, unwind and remove the drain bolt.
Step 4. (Optional) If you want to try get as much of the old oil out as you can, loosely screw in the drain bolt, lower the rear of the car and raise the front of the car higher and unscrew the drain bolt again tip all the fluids out.
Step 5. With all the old fluids out, screw in the drain bolt and proceed to fill up the housing with new oil via the fill hole using your pump or syringe (trust me the pump is worth it).
Step 6. You’ll know it’s full when fluid start streaming out. You can try jack the car up higher at the rear to try get some more new fluid in but not really necessary. From memory my S15 diff took about 1.4L (manual says 1.2-1.4L phew).
Step 7. Screw in the fill hole bolt and you’re done.
That’s it really, short and sweet! Not all work done on the S-Chassis is a pain in the arse!