front diff flush options. (1 Viewer)

[Darkdragon]

hello and thanks in advance any and all advice.

the old girl just turned 200000 miles old and i have started rebuilding the front axle rebuild. I new that i had a DS inner axle seal leak and that the gear oil mixed in with the grease. what i wasn't expecting was the primordial ooze that came out of the drain plug.

i have spoken with some TLC owners and they suggested that i fill the axle with diesel fuel drive it around 30 MPH for 10-15 minutes drain and repeat. this doesn't sit right with me. is this a recipe for destruction or sound advice? my first plan was to remove the differential and go at it with a couple dozen cans of brake clean. i'm open to suggestions.

 

[Tools R Us]

Refill with gear oil and change it sooner next time. Some migration between the knuckles and diff is common, so best to change more often than you would on a normal diff. Check the breather, I prefer to extend it higher and change it to free flowing with a cheap fuel filter.

 

[half k cruiser]

Just put 75w-90 in there and change it again in another 10k-20k miles. Its fine, my 94 looked like this and barely had any fluid in it and its showing no issues.

 

[Cruiserdrew]

Cheap gear oil, rapid changes will clean it right out. Diesel is a bad idea. No high pressure additives and it's a poor bearing lubricant at best. The one time I had to do this, it looked great on the second change out.

 

[jfz80]

While i would flush out a housing with diesel or kerosene i wouldnt want to drive it for its lack of lubrication as Drew mentions. Im in same boat and depending on how much has migrated up the axle housing tubes the flush is your best bet without tearing it open to flush housing. Mine hasnt cleared up to my satisfaction after 3 swaps yet :/

May want to check your breather as well. Not just the tube and terminus but the 90* fitting screwed into housing to see if it is plugged.

 

[Roadhouse78]

Diesel will wreck everything. New gear oil and don't worry about it.

 

[Tools R Us]

Moly is good lube, having some in there isn't a bad thing. When it becomes bad is thickening out of grade, making the oil too thick to properly cool the gears. Attempting to clean it runs the risk of not getting all of the solvent out, contaminating, breaking down the new lube for no good reason. If you are that paranoid, fill with gear oil, run ~500mi, drain, repeat, as many times as necessary until you think it's "clean". Not likely to do any good for the diff, but may help recover a piece of mind?

 

[baldilocks]

That "primordial ooze" contains molybdenum disulfide which is a good thing anyway. When you drain milk from a diff or gear box, it's time to be concerned.

 

[Darkdragon]

Refill with gear oil and change it sooner next time. Some migration between the knuckles and diff is common, so best to change more often than you would on a normal diff. Check the breather, I prefer to extend it higher and change it to free flowing with a cheap fuel filter.

thanks!
im looking into the ARB diff breather kit

 

[Darkdragon]

Just put 75w-90 in there and change it again in another 10k-20k miles. Its fine, my 94 looked like this and barely had any fluid in it and its showing no issues.

thanks!

 

[Darkdragon]

Cheap gear oil, rapid changes will clean it right out. Diesel is a bad idea. No high pressure additives and it's a poor bearing lubricant at best. The one time I had to do this, it looked great on the second change out.

thanks!

 

[Darkdragon]

While i would flush out a housing with diesel or kerosene i wouldnt want to drive it for its lack of lubrication as Drew mentions. Im in same boat and depending on how much has migrated up the axle housing tubes the flush is your best bet without tearing it open to flush housing. Mine hasnt cleared up to my satisfaction after 3 swaps yet :/

May want to check your breather as well. Not just the tube and terminus but the 90* fitting screwed into housing to see if it is plugged.

thanks!

 

[Darkdragon]

Diesel will wreck everything. New gear oil and don't worry about it.

thanks!
diesel just sounded like a bad idea.

 

[Darkdragon]

That "primordial ooze" contains molybdenum disulfide which is a good thing anyway. When you drain milk from a diff or gear box, it's time to be concerned.

thanks!