Serviced the diffs... (1 Viewer)

[Boom7750]

Changed out the gear oil last night in my f and r diffs. Old oil looked OK, but I had alot (like maybe a teaspoon or so) of a very pasty, oily "sludge" on the drain-plug magnet. It was black, and very smooth and pulverized. Didn't appear metallic, though it did adhere to the magnet. I have fairly new ARB lockers and ring and pinions in the diffs, and I'm wondering if these are sloughing off material as they wear in? This is probably the 4th gear oil change since the new components, and I use high-quality stuff. As far as I can tell, everything is working well...gears run cool and quiet, lockers engage/disengage perfectly.
Any ideas??
On a side note, I had a b*#ch of a time getting the drain plugs out, as I had banged one too many rocks on the metal rim thats suppose to protect the plug. The rim folded over to the point that I couldn't get a socket on the bolt. After alot of prying and a few hits on the socket with a BFH, I got everything apart. Replaced the drain plugs with hex-head ones...10mm. I'd recommend this to all before you bugger up yours like I did.

 

[xl715]

As far as I can tell from what you said it sounds fairly normal, as lomg as the material was a paste and no hard chunks came out. Although, how many miles have you put on since last diff fluid change?

 

[Cruiserdrew]

John-that bearding of metal dust is normal-to a point. All those new gears, side gears, spider gears etc have to wear into each other. I would go the opposite direction. Get a 5 gallon bucket of inexpensive gear lube like the Coastal 80w-90 at Autozone($20). Change the gear oil every thousand miles or so maybe 2-3 times, and then put in the quality gear lube like Mobil 1 or Redline for a normal service interval. If you really plan to wheel this truck, and I'm hoping to see it, you might consider a very high quality but conventional gear oil so you don't feel bad about dumping it after every time you go in the water. That is the direction I have gone with all 6 of my Cruiser diffs. As much as I like synthetics, I just can't justify synthetic lube in the diffs. At $8 per quart, it's just too expensive to not run for a full 30k service interval.

I buy Chevron Delo Gear in a 5 gallon bucket and it comes out to $3 per quart. This is really good stuff, and I don't cry when I have to empty my diffs.

 

[REDDER1]

Do you (or anyone else) have preferences for which Diff gear oil to use? I just changed mine..114K..first time..PO never did it. So, i was already doing what you suggested..I have the AUTOZONE Coastol gear oil in nit now..i will prob change out once it warms up a bit and then put the good suff in.
Prob is what is the good stuff??

joe

 

[Cruiserdrew]

As I said-I like the "Chevron Delo Gear" 80w-90 gear oil. It uses a different anti-wear additive chemistry which is borate based instead of sulfer/phosphate. It smells way better than regular gear lube and it doubles the warranty of some of the heavy truck axle builders like Rockwell-to 750,000 miles! I read on Chevron's site that it is the only conventional gear lube to do that, which is why I use it. I buy it from the local Chevron distributer (Hunt and sons) in Sacramento.

I have also used Mobil 1 gear oil as well, which is good but expensive. I use that in the transfer case on the 80. I thought gas mileage was marginally better with Mobil 1. Redline also has a great rep around here but is $$$ and hard to find.

Bottom line-I'll bet any main line, national brand will be just fine. Exxon, Valvoline, Castrol etc all better than no change at all. Use Mobil 1 gear oil if cost is no object. You are on the right track if you are updating your truck's neglected service.

 

[Boom7750]

CruiserDrew...Good advice. I'll look for the Delo...

 

[cruiserdan]

Chevron's mineral oils also get good marks from Carey.

I have always used Valvoline 80-90 in the diffs and 75-90 in the t-case. I use Valvoline mineral oil in the engine.

I am tempted to consider the Chevron stuff, heck I burn Chevron gas all the time