Differential fluid?
#1
Member
Thread Starter
Join Date: Sep 2013
Posts: 208
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Differential fluid?
I am replacing the two pinion seals next weekend on my Jeep because they are leaking. I have a Dana 30 and Chrysler 8.25 and I am curious as to what fluids I should fill the diffs with afterwards? Should I use a friction modifier?
#2
Senior Member
Join Date: Nov 2012
Location: Harrisburg, Pennsylvania
Posts: 918
Likes: 0
Received 3 Likes
on
3 Posts
Year: 1995
Model: Cherokee
Engine: 4.0L HO
75w90 in front, 75w90 in rear for "normal" use, 75w140 synthetic in rear for towing (or oversized tires and "hardcore" off-roading). You only need friction modifier if you have an LSD (limited-slip differential).
#4
Herp Derp Jerp
Join Date: Nov 2011
Location: Parham, ON
Posts: 18,251
Likes: 0
Received 12 Likes
on
11 Posts
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Yep, you're fine with 75w90.
If you like synthetics they're fine for use. If your plans for offroading include frequent trips through water don't bother as it will get really expensive. Gear oil should be changed any time your axles go for a swim... the seals keep oil in, not water out.
If you like synthetics they're fine for use. If your plans for offroading include frequent trips through water don't bother as it will get really expensive. Gear oil should be changed any time your axles go for a swim... the seals keep oil in, not water out.
#5
CF Veteran
Join Date: Oct 2013
Location: Denver
Posts: 1,589
Likes: 0
Received 1 Like
on
1 Post
Year: 99
Model: Cherokee
Engine: 4.0
Yeah if you're going through water & draining your oil often just use cheap stuff.
If you are in a dry area & doing steep stuff etc I'd say maybe do the 140. One thing you could do is get out 1/2 way through a trip and check the heat of your differential covers front vs back and if the rear is super hot, you could do the 140. Essentially you don't want the oil to thin out too much from overheating. I imagine that's what they are anticipating from towing & offroad use. I just put cheap 75W90 in there since I'm not doing much crazy ****.
Do heavy rock crawler guys run anything super fancy?
I love oil nerd stuff. Maybe its my time working with shocks
If you are in a dry area & doing steep stuff etc I'd say maybe do the 140. One thing you could do is get out 1/2 way through a trip and check the heat of your differential covers front vs back and if the rear is super hot, you could do the 140. Essentially you don't want the oil to thin out too much from overheating. I imagine that's what they are anticipating from towing & offroad use. I just put cheap 75W90 in there since I'm not doing much crazy ****.
Do heavy rock crawler guys run anything super fancy?
I love oil nerd stuff. Maybe its my time working with shocks
#6
Yep, you're fine with 75w90. If you like synthetics they're fine for use. If your plans for offroading include frequent trips through water don't bother as it will get really expensive. Gear oil should be changed any time your axles go for a swim... the seals keep oil in, not water out.
#7
Herp Derp Jerp
Join Date: Nov 2011
Location: Parham, ON
Posts: 18,251
Likes: 0
Received 12 Likes
on
11 Posts
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Really? I used to have a Tacoma that we would use to haul deer across a creek on our hunting property. I extended the diff breather lines up into the engine bay on the front and gas filler neck on the rear. I changed the fluids a couple times when making repairs or upgrading parts and never had any signs of water in the housings. Is this a common problem with the XJ?
Some guys just check for water and everything's fine, but I wouldn't risk trashing the gears and bearings to save $10 on gear oil.
Trending Topics
#8
Depended on how much rain we had, but at times it was almost to the tops of the tires. I agree that I would rather change the oil than rebuild the axle that's why I'm asking.
Last edited by JDHDrum; 11-25-2013 at 06:20 PM.
#9
Junior Member
Join Date: Nov 2013
Location: Baltimore, MD
Posts: 68
Likes: 0
Received 0 Likes
on
0 Posts
Year: 2000
Model: Cherokee
Engine: 4.0L
I got ta believe that somebody out there researched and found a double lip seal that fits this aplication... I mean, after all don't outboard motors have a spinning shaft with water on one side of a seal and oil on the other ???
#10
Herp Derp Jerp
Join Date: Nov 2011
Location: Parham, ON
Posts: 18,251
Likes: 0
Received 12 Likes
on
11 Posts
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Sure do... No idea if such an animal exists in an automotive application. Some military vehicles use air to slightly pressurize the axle, enough to keep water out
#11
Junior Member
Join Date: Nov 2013
Location: Baltimore, MD
Posts: 68
Likes: 0
Received 0 Likes
on
0 Posts
Year: 2000
Model: Cherokee
Engine: 4.0L
It's a simple matter of finding out the OD, ID, and width measurements and then looking up in a seal manufacturers catalog for a good fit with double lip seal... They likely will have several to choose from that are made of differeing materials.... I'm thinking Viton would be a good choice...
#12
Yep, you're fine with 75w90.
If you like synthetics they're fine for use. If your plans for offroading include frequent trips through water don't bother as it will get really expensive. Gear oil should be changed any time your axles go for a swim... the seals keep oil in, not water out.
If you like synthetics they're fine for use. If your plans for offroading include frequent trips through water don't bother as it will get really expensive. Gear oil should be changed any time your axles go for a swim... the seals keep oil in, not water out.
they aren't a check valve. water comes in the breather vent or bad seals.
#13
Herp Derp Jerp
Join Date: Nov 2011
Location: Parham, ON
Posts: 18,251
Likes: 0
Received 12 Likes
on
11 Posts
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Seals don't take that long to become 'bad' lol. Jeep axle seals aren't designed to stop water. There's a significant difference in viscosity and molecular size between H2O and 75w90
Thread
Thread Starter
Forum
Replies
Last Post
cpnwrench
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
13
02-15-2024 08:09 AM
jmsummers2012
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
53
04-30-2021 02:35 PM
tleed
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
3
10-04-2015 01:20 PM
Lightning_19k
Modified XJ Cherokee Tech
14
10-03-2015 09:52 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)