Noticed a strange vibration coming home from a 400 mile trip on the interstate, cruising around 75-80 mph. Did my normal scheduled maintenence and upon checking the fluid in the rear diferential noticed the fluid was real dark almost like used motor oil, and a lot of what almost looked like assembly lube(grey pastey) on the plug along with some metal shavings. The truck is an 03 F350 DRW 6.0 trqshift, and 410 gears. And only has just under 18,000 miles. Anyone have any problems with theirs, gonna take mine to the dealer Monday and have them check it. Just wanted to get some feedback from all of you, Thanks, Brian.

 

Doesn't sound good. I don't know your model and maybe the diff fluid is different but in general, dark fluid at 18,000 miles and lots of grey pasty stuff means you have a problem. The grey pasty stuff is ground up metal mixed with oil. Metal shavings should never be found except for maybe 2 or 3 grain of rice sized on the first change, even that wouldn't be best.

A little paste is normal. I would say maybe about a pea's worth at 50,000 miles. The fluid even at 50,000 should probably be dark(at worst) clear honey color. I tow an 8,000# trailer and my fluid looks great every change, almost like fresh fluid.

I am not an expert with diffs but would guess either your gears were not properly adjusted or there is a problem with the clutches, if you have an LS rearend.

I am hoping either you are still under warranty or the dealer understands that this is most likely an improper factory adjustment error, or they are merciful. A differential just isn't supposed to die this early unless it is abused or a factory defect.

By any chance have you driven thru really deep water, say 2feet or more? If you got water in the diff then you could get some serious damage, but usually you will see kind of a light to dark brown milkshake or pudding looking deposit in the diff.

Good Luck,

Jim Henderson

 

Hey Jim, i havent been through any water that deep, and i only occasionally tow my single open car trailer 5000lbs tops, just started noticing a strange vibration, should be covered under warrenty with 18000 miles.

 

One other thing. You might post this under clutches transmissions differentials section. There are guys there with way more experience than me.

But either way, metal shavings is not good.

I can't imagine any warranty not being at least 36,000 miles and should cover this kind of problem.

Good Luck,

Jim Henderson

 

Took truck to the dealer today and they said nothing is wrong with it, normal for the color, the vibration is from the tires, only found minimal shavings, and the grey stuff is from the lube for the clutches. Guess we will have to wait and see.