IRS Differential oil quantity.

[Green Roadster Build.]

Curious if the IRS limited slip diff that comes with the kit has shipping oil in it. I filled mine without checking and it took less than one quart and it’s supposed to take 1.2 Quarts + 3 oz of friction modifier.

[robmccon]

Just went through the same thing with my IRS. Took about 3/4 qt.

[F500guy]

I ended up with a drain pan full, it did not take the recommended amount.

[Ford & Jeep Fan]

If you are running a true trac,....... to me they look like they have Much more mass than a OEM carrier or a OEM lS carrier. If they really do have a more metal they will take up some of the lube Capacity.

[toadster]

I got my diff from Forte, he had to drain prior to shipping - surprised they ship with fluid to be honest... but sounds like it's happening

I believe I did about 1.75 qts of Valvoline SynPower SAE 75W-90 Full Synthetic Gear Oil which has friction modifier already included

[narly1]

Perhaps this chart is of use:

axlelubeUS (1).pdf