Differential Fluid Change

[dp88]

Im going to be changing my oil tonight and figured I would change my rear diff fluid while I was there. I have read 75w90 is what i need but how many bottles? I dont have my manual with me right now. And what about a friction modifier? I have the 8.8 Torsen rear end.

 

[cammeddrz]

until the fluid drips out the fill hole. unless your rear diff is the one with the check plug abouve the center of the pinion at which point around 1" below the fill hole. and in fact 1" below the fill hole is acceptable in both cases. its not an exact science, i just fill it til it pours out in either case though (i worked 5 years at jiffy lube, i have changed the fluid on hundreds, if not thousands of diffs)

 

[dp88]

Sorry should have been more clear I mean like one or two bottles I knew where to fill to just dont want to not buy enough. Thanks for answering me though.

 

[cammeddrz]

usuall 2 quarts is plenty, except on big diffs like the dana 60, 80 etc, or the gm 12, and 14 bolt diffs. but on yours 2qt will be a little shy

Differential Oil Capacity


*edit, here is the excerpt from the service manual:
Front Axle 1.54L (3.25 pt)

Lubricant Level mm (in) 9.56 (0.38) below bottom of axle cover filler hole

Rear Axle 2.37L (5.0 pt)

*edit again, here is the fluid specifications from service manual:
Differential Fluid Type



Front Axle SAE 80W-90 Thermally Stable 4x4 Axle Lubricant

Rear Axle


7.5 / 8.8 Inch SAE 80W-90 Premium Rear Axle Lubricant

8.8 Inch High Torque SAE 75-W140 Synthetic Rear Axle Lubricant

 

[dp88]

Thanks a lot! I hear about friction modifier, do I need that in the 8.8 Torsen rear end?

 

[AllanD]

Im going to be changing my oil tonight and figured I would change my rear diff fluid while I was there. I have read 75w90 is what i need but how many bottles? I dont have my manual with me right now. And what about a friction modifier? I have the 8.8 Torsen rear end.

BEFORE YOU DO ANYTHING

Read the tagS (YES, PLURAL!!!)
on the diff.

There is a possibility that your diff is already filled with the Ford Special synthetic 90w-140 gear lube and if you change it it MUST be refilled with the same stuff.

that gear oil is weird stuff and mixing even a small ammount of it into "other oil" causes the whole batch to turn into a goey mess resembling pre-packaged chocolate pudding.

It takes only about a pint to turn 3 gallons of engine oil into a solid rubbery lump.

BTW, that shit is $22/quart.

so thiunk hard about changing it if you don;t have to....

but if your axle IS equipped with that special oil there will be a SECOND tag on the diff cover telling you so.


AD

 

[dp88]

im at work so cant check now but I have always only seen one tag...

 

[cammeddrz]

It takes only about a pint to turn 3 gallons of engine oil into a solid rubbery lump.

i have never had that occur in all my years, but i will certainly keep an eye out for it in the future.

btw why would you ever mix 140 with engine oil to experience this?

 

[cammeddrz]

im at work so cant check now but I have always only seen one tag...

well alldata only listed the 75/140 syn for the 8.8 of that year, if you can't find the other tag it wouldn't hurt to call the dealer with your vin to be clear though..........alldata has been wrong before

 

[dp88]

well I could have missed it I was never really looking for it before just going on memory. If it is the 75/140 can I get that at the parts store or no? Thanks for all the help guys.

 

[cammeddrz]

If it is the 75/140 can I get that at the parts store or no? Thanks for all the help guys.

yeah, all major parts stores stock it. and it is my understanding that all major brands of 75/140 have the friction modifier in the fluid

 

[Mac]

The '03' manual shows it needs 5 pints of 75W-140 and 4 oz of the friction modifier for the torsen rear end.
Dave

 

[feellnfroggy]

ANy axle with the limited slip requires the friction modifier, When I swapped a pre 99 8.8 into my 2000 v6 mustang the mechanic said all ford axles required the friction modifier, but htat sounded kinda extreme as they did come out with it till late 80's I htink. But I dont htink it will hurt to add it anyways.

 

[PickupMan04 FX4 L2]

Ok you guys are going to make me bust out my manual for this huh.. there is too much heresay going on!

pg229 IN THE 2004 OWNERS GUIDE

rear axle lubricant: (fx4 level 2 only) 75w-140 synthetic rear axle lubricant
2.5 to 2.6 liters or 5.25 to 5.5 pints

note: (annotation number six):
add 118 ml (4oz) of additive friction modifier xl-3 or equivalent
FORD SPEC: EST-M2C118-A

THIS APPLIES ONLY TO ANY RANGER WITH A ZEXEL TORSEN T-2 TORQUE SENSING DIFF.

CLICKY PDF

APPLICATION SHEET CLICKY

 

[feellnfroggy]

So as was said above, any axle with limited slip need the FM. DOesnt sound like hearsay to me......WHat I said I "heard" was the keyword ANY. Which would include open diffs and posi's. That was the hearsay, but did not apply to your axle.