Can installing extreme pressure additive in rear end differential cause a problem?
Asked by guruquestionguy Nov 26, 2016 at 01:02 PM about the 2014 Ford F-150 Platinum SuperCrew
Question type: Maintenance & Repair
I had my F 150 serviced in Sept. The dealer recommended the rear end oil
be changed. The service ticket states "installed 02362: limited slip add /
extreme pressure"
Shortly after the service, I noticed an unusual noise which turned out to be
from the differential gears. The dealer replaced the gears and bearings.
The replacement service ticket does not list "02362: limited slip add /
extreme pressure" as being reinstalled during the repair.
7 Answers
Friction modifier is essential to the limited slip working properly. I wonder if the dealer forgot to install the gear oil the first time. I use the official Ford additive in my F150 and don't have any problems. I don't know the part number but it is called the Ford Fluid XL-3 Friction Modifier Additive .
guruquestionguy answered 7 years ago
Original service performed in Sept lists the following: -01482 Diff Fluid Syn 75W-140 -02632 Limited Slip Add / Extreme Press There is no mention of "XL-3" or anything called "Friction Modifier Additive" After replacing the failed gears the service ticket does include the "XL 3" Additive (no part number provided) along with the following: - 01482 Diff Fluid 75W-140 There is no mention of the 02632 Limited Slip Additive / Extreme Press. being installed after the replacement of the differential gears. I believe you are on to something. Thanks for the reply.
Not installing the friction modifier should not harm the gears. It would make the differential chatter on tight turns.
I tried looking up that part number and came up with nothing. What is it exactly?
The first go around there was no 01482 Diff Fluid 75W-140 added to the diff?
guruquestionguy answered 7 years ago
The first service ticket does include the 75W-140 but not the XL-3 additive. I drove for about 15K miles until the noise became more of an issue and returned to the dealer for investigation. After inspection, the dealer replaced the diff gears and rear bearings & seals - no questions asked. They provided me a rental while performing the repair and did not charge me a dime.
guruquestionguy answered 7 years ago
The original service ticket stated: "installed 02362: limited slip add / extreme pressure" but made no mention of "XL-3" additive. The corrective repair (just completed) included the "XL-3" additive and does not identify the "installed 02362: limited slip add / extreme pressure"
