Unknown 75w140, 12 Jeep Wrangler, 62K

[TXHunter]

Fluid was not replaced at the time of the sample. We just purchased this vehicle and had UOA's performed on the front & rear diff. Make/Model: Dana 44 Differential (Rear) Vehicle: 2012 Jeep Wrangler Rubicon Unlimited

Code:

OIL             Unknown (Factory fill?)
MILES IN USE    Unknown
MILES ON UNIT   61,945
SAMPLE TAKEN    6/19/18		
MAKE UP OIL	0		

ALUMINUM	0		
CHROMIUM	20		
IRON		353
COPPER		2		
LEAD		0		
TIN		0		
MOLYBDENUM	2		
NICKEL		8		
MANGANESE	7		
SILVER		0		
TITANIUM	0		
POTASSIUM	2		
BORON		226		
SILICON		14		
SODIUM		5		
CALCIUM		9		
MAGNESIUM	2		
PHOSPHORUS	2228
ZINC		21		
BARIUM		1		
     
SUS @ 210F	72.6		
Visc @ 100C	13.63		
Flashpoint	410		
Water %		0.0		
Insolubles %	0.1
TAN		3.7

Blackstone comments: This sample from the rear diff looks pretty good too. We're not sure if it's the factory fill or not, but regardless, these results don't point to any issues. Iron and chrome are higher than we saw from the front axle, but that's not anything to be concerned about. The rear diff typically sees quite a bit more use so it's common to see more metal in its oil. No contamination was found and the viscosity is in spec. Insolubles (solids) are pretty minimal at 0.1%. The TAN of 3.7 is still low enough to show no excess acidity. Nice pair of reports! Just check back in 20K miles or so.

 

[Chris142]

I would have changed it. therear axle fluid in my Jeep was gray @36k

 

[Popsy]

Viscosity seems pretty low for a 140, I would have changed it too, even if the it looked fine. I guess it's the BITOG way!

 

[Rand]

Iron at 353? I would change it.. looks like possible factory fill.

 

[TXHunter]

Universal average for Iron is 731, so it's still well below the typical report for a Dana 44.

 

[FastLane]

Probably factory fill

 

[dnewton3]

Presuming this is FF, the wear is not bad at all. After all, for FF, all the "break in" is still in there. The average is 5.7ppm Fe / 1k miles. With break in metals still floating around after 62k miles. I've seen younger Chevy engines shed that much Fe after several OCIs. This isn't bad whatsoever.