2002 F150 Differential Oil

[LatLong]

I have a 2002 F150 and I'm going to be replacing the rear axle bearings. On the axle the tag it says 75-90 gear oil and my Chilton manual says to use 75-140 oil with a friction modifier. I'll go with what's on the axle tag but what I'm wondering is why the difference? As far as I can tell from the tag it doesn't have limited slip.

[Scott K]

You should be using 75w140 in the rear, and 75w90 in the front. If it has LS rear, and about 90% of them did, then you want to add the additive for it. To find out if it has limited slip, jack up the back end spin one side, does the other side turn? Or does it sit still? If it spins, it has limited slip. Very few didnt have it, so I would count on it having it.

Throw the tag away that has 75w90 on the rear case, that should have been taken off on the PDI when it was new.

[Macgyver55]

To find out if it has limited slip, jack up the back end spin one side, does the other side turn? Or does it sit still? If it spins, it has limited slip.

I would add to clarify, if it spins the same direction as you are turning its limited slip, if it turns the opposite directionas you are turning it would be an open differential.

[Scott K]

Oops, I forgot to type that

Also put it in neutral

[Walleyehooker]

Easier way is to google ford LS axel codes and look in your glove box at the code sheet.

[Walleyehooker]

Axle codes

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Just check the axle code on the sticker

19 — 3.55 non-limited slip (Econoline, F-150)

18 — 3.08 non-limited slip (F-150)

17 — 3.31 non-limited slip (Econoline)

H9 — 3.55 limited slip (F-150, F-250)

B6 — 3.73 limited slip (F-150, F-250)

24 — 3.73 (Econoline)

32 — 4.10 (Econoline)

35 — 4.09 (Econoline)

34 — 3.73 (Econoline)

39 — 3.55 (Econoline)

52 — 4.10 (Econoline)

56 — 4.10 (Econoline)

81 — 4.63 (Econoline)

27 — 3.31 non-limited slip (F-250)

26 — 3.73 non-limited slip (F-250)

41 — 3.27 non-limited slip (Explorer/Mountaineer)

45 — 3.55 non-limited slip (Explorer/Mountaineer)

46 — 3.73 non-limited slip (Explorer/Mountaineer)

42 — 4.10 non-limited slip (Explorer/Mountaineer)

D1 — 3.27 limited slip (Explorer/Mountaineer)

D4 — 3.73 limited slip (Explorer/Mountaineer)

D2 — 4.10 limited slip (Explorer/Mountaineer)

84 — 3.45 non-limited slip (Ranger)

86 — 3.73 non-limited slip (Ranger)

87 — 4.10 non-limited slip (Ranger)

89 — 4.56 non-limited slip (Ranger)

F6 — 3.73 limited slip (Ranger)

F7 — 4.10 limited slip (Ranger)

92 — 3.08 non-limited slip (Ranger)

R5 — 3.55 limited slip (Ranger)

91 — 3.27 non-limited slip (Ranger)

96 — 3.73 non-limited slip (Ranger)

R6 — 3.73 limited slip (Ranger)"

[LatLong]

I'll have to jack it up and test it. The door sticker is gone because the door was replaced before I got it and no sticker on the new door. There isn't anything in the glove box. The axle tag on the diff cover says 3.31 gears but I can't make out if it has a limited slip.

I've done axle bearings on an open 8.8" rear end, if this one has a limited slip are there any steps I need to watch out for or tricks that I need to know?

[Walleyehooker]

Yea now that you mention it I think ford does put them on the door. Sorry about that I havnt had a ford for a while.

[fishing tech]

If you have the tag off of the diff and it has 3.31 on it it is not a limited slip unless someone changed the carrier assy. Limited slip would have 3.31L on it.

[LatLong]

I jacked up the truck last night and spun the wheels. No limited slip. So I wouldn't add the friction modifier right?

[Scott K]

I jacked up the truck last night and spun the wheels. No limited slip. So I wouldn't add the friction modifier right?

Correct