post your latest differential fluid change
- Thread starter electrolover
- Start date
2008 Ranger with a salvage yard rear axle (pinion bearings froze on the original axle and it was cheaper to put a salvaged unit in than rebuild the original, which had 190k on it). He filtered and reused the fluid from the old axle, which I'd just put in prior to taking it to him. It was Supertech 75W-90. I trust him, but wanted brand new fluid in it just the same. When I pulled the diff cover off, the fluid came out looking clean, with no metal bits or any other visible contaminants. The internals of the diff looked healthy, which I was happy about. Cleaned the old gasket seal off, replaced with a Felpro, and filled it up with Valvoline 75W-90. The extra $4 per quart over the Supertech was worth it just for the squeeze bag and not having to use my pump. 
If anyone's curious why I put new fluid in prior to taking it to the shop, I didn't know that the issue was frozen pinion bearings at the time. I wanted to put eyes on the inside of the diff to see if I could figure out what was going on, which meant having to drain the old fluid and put new fluid in. Once I saw the diff gears looked good, I knew it was something else and let someone more knowlegeable than me fix it.
If anyone's curious why I put new fluid in prior to taking it to the shop, I didn't know that the issue was frozen pinion bearings at the time. I wanted to put eyes on the inside of the diff to see if I could figure out what was going on, which meant having to drain the old fluid and put new fluid in. Once I saw the diff gears looked good, I knew it was something else and let someone more knowlegeable than me fix it.
- Joined
- Sep 26, 2010
- Messages
- 9,837
What would YOU suggest when the specifications call for 75W-140?
- Joined
- Sep 26, 2010
- Messages
- 9,837
(Since I did not see a Post Your Latest Transfer Case Fluid Change thread)...
2019 Jeep Wrangler Unlimited Rubicon
NV241OR Transfer Case
30,000 Miles
Out:
Mopar ATF+4
In:
Ravenol ATF+4
2019 Jeep Wrangler Unlimited Rubicon
NV241OR Transfer Case
30,000 Miles
Out:
Mopar ATF+4
In:
Ravenol ATF+4
4WD
$50 site donor 2025
Did you take the guard off or let ‘er rip ? I made a little “gutter” from that HD Costco foil (Reynolds) and left the steel in place … That fluid looked way better than diffs …
4WD
$50 site donor 2025
4WD
$50 site donor 2025
Modern VM’s are far better these days ? 0W40 ? Just have an objective look at which OEM’s approve it …
- Joined
- Sep 26, 2010
- Messages
- 9,837
I had some seeping in my 08 JK, so I took off the Rancho rear diff slider, drained out Valvoline 75w140 syn, removed the cover and put Permatex red on it and re-sealed it, reattaching the Rancho. I then filled it with new Valvoline 75w140 synthetic. Those Flex Fill bags are THE BEST. Love it! 153,640 miles on the Jeep and the ring gear teeth looked perfect.
Laughable theory.
2015 Toyota pickup, 13,250 miles.
Out: Factory fill, came out very very dark gray, almost black
In : Mag1 80W-90 GL-5
Out: Factory fill, came out very very dark gray, almost black
In : Mag1 80W-90 GL-5
1985 Mazda RX-7 with LSD, 137k miles
Out: Unknown, possibly factory fill SAE 90
In: Valvoline 75W-90 synthetic and Ford friction modifier
There's no removable cover on this differential, fluid is pretty easy to change with a drain and fill plug. The magnet was mildly frothy but no metal pieces.
Out: Unknown, possibly factory fill SAE 90
In: Valvoline 75W-90 synthetic and Ford friction modifier
There's no removable cover on this differential, fluid is pretty easy to change with a drain and fill plug. The magnet was mildly frothy but no metal pieces.
I put new pads and rotors on the rear of my dads 2016 3500HD Chevy. On these 11.5” AAM axles for the dually trucks, you have to pull the axles and hub assemblies to replace the rear rotors. It was a short OCI but it’s easy enough to change the rear diff fluid while I’m under there and doesn’t cost much, plus you lose some fluid when you pull the axles out. I used around $650 in parts (a friend let me have the brake parts at his cost) for a complete brake job and rear diff fluid change. The dealership will charge about $2,500 to do a brake job on one of these duallys. The rears call for about 2 hours per side to replace the pads and rotors. I went with Carquest semi-metallic pads and their platinum painted rotors. I got OEM seals and gaskets from my local Chevrolet dealer.
I priced OEM parts online and with shipping it was gonna be about $1000 for front and rear pads, rotors and the 2 seals and 2 gaskets.
OCI: 16,127 miles, 69,958 on the truck.
Out: 50/50 mix of syn 75w90 and 75w140.
In: almost 4 quarts of full syn 75w140.
I priced OEM parts online and with shipping it was gonna be about $1000 for front and rear pads, rotors and the 2 seals and 2 gaskets.
OCI: 16,127 miles, 69,958 on the truck.
Out: 50/50 mix of syn 75w90 and 75w140.
In: almost 4 quarts of full syn 75w140.
Attachments
2012 Nissan Qashqai (Rouge) 4x4 1,6 liter R9M diesel, 175000 km.
Rear diff out probably original fill. In leftovers from another cars, mostly Castrol Syntrax LSD 75W-140 GL5 and a bit Fuchs Titan Sintopoid FE 75W-85 GL5. Recommended fill is 80W-90 semi synt GL5, ca 0,6 liter.
Transfer case behind engine: Oil maybe changed once in the cars lifetime, but probably long ago. Fill was Fuchs Titan Sintopoid FE 75W-85 GL5 and noname GL5 75W-90. Recommended fill is GL5 0,4 liter 80W-90.
Rear diff out probably original fill. In leftovers from another cars, mostly Castrol Syntrax LSD 75W-140 GL5 and a bit Fuchs Titan Sintopoid FE 75W-85 GL5. Recommended fill is 80W-90 semi synt GL5, ca 0,6 liter.
Transfer case behind engine: Oil maybe changed once in the cars lifetime, but probably long ago. Fill was Fuchs Titan Sintopoid FE 75W-85 GL5 and noname GL5 75W-90. Recommended fill is GL5 0,4 liter 80W-90.
2000 Jeep cherokee with a 280,000 mile 1999 Cherokee front differential.
Front
Out: 80w/Water with lots of flakes from a destroyed locker.
In: Supertech 85w-140 with a new Torqmasters locker.
Rear
Out: Coaldust/Mud/Water
In: Supertech 80w-90.
Front
Out: 80w/Water with lots of flakes from a destroyed locker.
In: Supertech 85w-140 with a new Torqmasters locker.
Rear
Out: Coaldust/Mud/Water
In: Supertech 80w-90.
2008 Ford Crown Victoria P71:
Out: unknown
In: RL 75w140 + Lubegard Gear
158,773 miles.
Shop in Phoenix had said the fluid was quite dirty although I found it to be not bad, sort of an amber color. Also tried a different technique on this one due to a time constraint, just pumped old fluid out through the fill plug and got almost the whole capacity. Was very easy and worked perfectly!
Out: unknown
In: RL 75w140 + Lubegard Gear
158,773 miles.
Shop in Phoenix had said the fluid was quite dirty although I found it to be not bad, sort of an amber color. Also tried a different technique on this one due to a time constraint, just pumped old fluid out through the fill plug and got almost the whole capacity. Was very easy and worked perfectly!
Last edited:
Similar threads
