Front and Rear Diff Fluid

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jan 2, 2007
Threads
5
Messages
19
Location
Leland, MS
About how much fluid should I expect to add to the front and rear diff's if i drained them? And any suggestions to a good 90 weight gear oil to use for this application?
All dumb comments like "until they ae full" will be greatly appreciated!:)
 
About how much fluid should I expect to add to the front and rear diff's if i drained them?

Check the capacities in your owner's manual.

Oh, and don't drain them until you've made sure you can get the fill plugs off! :doh:

Curtis
 
The diffs take roughly 3.5 quarts each. 7 Should do both, but the front uses a bit less and the rear a bit more. Believe it or not, you fill untill they are full-ie the oil runs back out the fill hole.

Any name brand 80w-90 will work well. If this truck is new to you, I'd run a cheap gear oil for a few months to flush out the diffs and then run a synthetic like Mobil 1 75w-90.

Remove the fill plug first for obvious reasons.
 
On a side note (reads hijack) Does a lift change the amount of lube the diffs can hold? I would think the change in caster would make a little difference, prolly not much but a little?

Back to the thread.
 
You can use some expensive RedLine 75-90

$9 per qt.... Yikes
 
IIRC 2 gallons does the front rear and transfer case,

you will want to change that fluid in the transfer also, hardest working two quarts of fluid in an 80 series. might as well as do it at the same time you will already stink of 90wt.
 
i guess to get to the drain and fill plugs for the transfer you have to remove that skid plate?
 
IIRC 2 gallons does the front rear and transfer case,

you will want to change that fluid in the transfer also, hardest working two quarts of fluid in an 80 series. might as well as do it at the same time you will already stink of 90wt.

stink!!!??!!!!

I love the smell of 90wt......Usually it means I've been near a landrover....or working on the cruiser...I just changed the rear diff lube thge other night....next up as time permits transfer/front diff....
 
i guess to get to the drain and fill plugs for the transfer you have to remove that skid plate?

to get to the drain yes, 3 bolts and it comes right out,



stink!!!??!!!!

I love the smell of 90wt......Usually it means I've been near a landrover....or working on the cruiser...I just changed the rear diff lube thge other night....next up as time permits transfer/front diff....


To each his own personally don't like the sulphur smell. some 90 wts stink more than others.
 
as far as the impact of axle rotation and a lift....can you jack the front end or rear end up enough to rotate the pumpkin so the fill plug is "level" again"
 
Thanks for all of the help. All fluids changed!! I love the smell of 90 weight in the morning!
 
On a side note (reads hijack) Does a lift change the amount of lube the diffs can hold? I would think the change in caster would make a little difference, prolly not much but a little?

Back to the thread.

It would make a difference but it is not an issue. Fill it till it's full. More is better IMO, but it's a "guideline". Big gears in an oil bath. As long as they're splashing in the oil they'll be happy.
 
After you flush out the diffs with some conventional oil I would reccomend Red Line 75-140w if you plan to abuse it off road because if definitely offers more shock protection for your gears. Royal Purple, Mobil One and Amsoil also make a great gear lube that will protect your diffs better than standard lube.
 
I used mobile 1 synthetic. 75w90. I let the fluid drained overnight. Front was close to 3 quarts. Rear ran out after 3 quarts. Need to buy more. Don’t use the syringe pump. Faster and easier with the cheap harbor freight one. Tip. Use a cardboard box so the hoses won’t touch the sandy pavement and to contain everything inside; catch the overfill. I placed the pump against the axle and pump. Easier than holding it with your left or right hand. Make sure you replace the washers.

IMG_0466.jpeg


IMG_0467.jpeg
 

Users who are viewing this thread

Back
Top Bottom