I follow Lake Speed closely, and I'm well aware of the engine break-in protocol, which I do. I was wondering if there was a guideline on break-in fluid changes for diffs as well? I did my first one at 899 miles
I'd ask the manufacturer of the ring and pinion gears and/or posit unit. Most cars and truck run on the factory fill for the life of the vehicle without a change at all.. I don't recommend that, just pointing out that set up properly most gear sets are pretty tough.
I have done R&P sets from Richmond, Yukon and Motive and pretty much followed this procedure and been fine.
For brand new cars / trucks, the few that I have owned, I just follow the owner's manual which is generally no towing for the first x (500, 800 etc.) miles.
I mostly do 25k on a new vehicle and within a few thousand miles if a used car. After that, I generally run 75k for both front & rear. Subaru front diff is brutal on even Amsoil, Valv synthetic. Exception being BMW's in my sig. I simply do diffs, trans fl, and X-Drive locker every 50k. Amazing to me how small even the X3 lockers are.
If i were to change the gear oil in my truck ( the one in my signature ) to say high performance lubricants, what mileage should i wait until its finished breaking in?
Its used mostly for towing, I have about 2200 miles on it now. When would it be done shedding metal?
I think once its broken in , i would use HPL Differential life, and change it say every 25k.
Originally Posted By: Slick17601
Originally Posted By: Hootbro
Why so early?
Always a good idea for an early drain on a differential. After break-in, there's very little wear.
Yep! A high percentage of the total lifetime of wear metals generated by an axle come in the first few thousand miles (or kms in this case) of operation while the axle breaks in. Since there is no filtration, getting those chunks out is a good thing in the long run.
Obviously, the OEM have calculated how far things can be pushed on the OCI, so if you were to drive the car 100K or so and trade it in, you may...