Changed my Rear Diff fluid...

I have about 6,000 miles on my truck. We recently did a "HOLY JIM" (dirt road with alot of puddles) and after going through alot of water i was paranoid about the rear diff oil. Well my paranoia was correct... it was really milky and actually has trace amounts of dirt in it( noticed muddy crud in the drain pan after i emptied it.) Also, to my surprise, after only 6k miles, the magnetic drains plug had quite a bit metal particles clinging to the magnet (black sludge). Im hoping it was due to break in and there isnt anything wrong internally. Well see in 10k when i change it again.

I used

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 Synthetic Mobil 1 gear oil... Couldnt find 75W-85 (not that 75W-90 is a big differance)

I also checked the Tranny and Tcase. Tcase is clean but the Tranny is milky so thats next. Would have done it today but i only had 3 quarts and nobody was open today

 

what was your method for checking the tranny?

 

pulling the fill/check plug and stuck my finger in the oil and it was clean but i wasnt convinced because the water would be at the bottom so i drove around for 10mins to mix it up. then pulled the plug again and it was yellow and milky. The tcase oil was nice and clear...so i know the tranny oil has something going on just like the rear diff. Im an advocate for synthetics so ill change both the tcase and tranny oil with synthetic and update this thread...

 

Did both my diffs and tcase at 1000mi with mobil 1 LS 75-90. Factory fill oil looked like shit, milky grey. Plenty of metal goo on the drain plug from break-in, no doubt.

In any event, it doesn't sound like yer diff was anything abnormal.

 

I didnt think so but after going through that much water it made me paranoid. And GOD does that shite stink. Every time i change gear oil on anything i smell it for days lol.

thats the oil i used. Im hoping it will allow the drivetrain to last longer and ive heard it makes for smoother shifting in the 5speed. Also alot less wear and better lubrication so maybe better gas mileage and longer lasting drive-train? Fingers crossed.

 

If anyone in Socal wants it done ill do rear diff or manual tranny for $60 bucks including the oil. $75 for the front. and $45 for the tcase.

 

Thanks for sharing your experience. It is good to know.

You going to do the diff breather mod anytime soon?

Those Holy Jim videos were awesome.

 

I didn't pick up any extra mileage, but I've had it in there for about 3k miles now and haven't had a single problem in any kind of driving, and I broke out every traction toy on my fully load TRD OR package last weekend with the snow. Stuff seems to work peachy keen.

Probably gonna switch to Royal Purple Max Gear at the next change, not because the Mobil 1 had any problems, but because the thought of RP's high film strength coatin' my ring n pinions gives me the warm n fuzzies.

I'm sure any synthetic can only do good things for wear protection.

 

yea i have to get the parts from toyota. I have the fuel line and hose clamps.

 

Awesome! It's on my list to do as well. Kudos to you for checking your diff. I'd have been paranoid too.

 

FYI, I found 1/4in ID fuel line almost IMPOSSIBLE to squeeze over the new diff breather plug and ended up going with 3/8in ID high pressure hose. Worked out well. Recommend taking the new breather plug with you to Lowes or wherever you get your tubing so you can be sure it sizes correctly.

 

Thanks, ive got extra fuel line from other stuff and fuel injection clamps...

 

Not sure about toyota but in the final drive on my honda motor cycle looked milky grey and was told it was the special moly grease they put on the gears to help break in and when it mixed with the gear oil it looked milky, and not to change till 10,000 miles, just ask'n to see if toyota puts this type of break in grease on their gears and if so that might explain the grey milky color..Dunno...

 

after letting the diff oil sit there was maybe 1/2 once of water in the old oil...there was probably more but may have evaporated?