rear diff oil analysis........results

[CanadaKev]

Changed the rear diff oil at 15K miles/500 hrs.(first change).
Grabbed a sample(out of curiosity) and sent it to Finning for a look-see.
Came back today coded AR(Action Required) because of a high Fe(Iron) content @642ppm.
Have any of you sampled your rear diff oil? And what were your results? Is an iron level this high something I need to be concerned about. If so how concerned?
:(
TIA, Kev

[pinehill]

Kev,

Looks like you tow heavy and tow often. You must have missed the recommendation to change out the rear diff. lube after the first 500 miles of heavy towing. When I dropped mine at that point, it contained a lot of metallic particles.

Your gear teeth are now well worn-in; you shouldn't experience much more wear from here on out. You may have decreased the life of the diff. a bit, but if you're now useing a good synthetic, I wouldn't lose any sleep over it.

[SoCalDMAX]

The gears shed a lot of debris in the first 500mi as well as whatever was still on it from machining. It's recommended to change it at 500mi to flush this out, but I agree with pinehill, no real biggie.

I'm sure you noticed some metal fuzz on the drain plug magnet. The good news is I've been monitoring diff temps with a probe and they seem to be very low (no higher than 160* on mine) but that's only towing 6,000lb and with a Mag-hytec cover which helps dissipate heat. Since they come filled with synthetic lube, and the gears never got very hot, I'm sure it was just normal debris.

Regards, Steve

[IndigoDually]

A good deal of the junk in the oil is the friction material from the clutches in the locker. One of the concearns in the begining is the heat generated from the ring and pinion breaking in degrading the oil and contaminating it.
All in all I would not worry about it. I just changed mine for the second time at 15,000 mi. and I won't be changing it again for a long time.

John