Differential Question

[Cr33p3r]

I am filling the 9"w/ Royal Purple 75-90 gear oil I know that when it is a posi you have to add the posi additive, but if it has a locker do you have to add any additives?

[Brody]

I have never run any additives in any locker or spool I have run since I got my first 4x in the late 60s.....and I have had lockers in all of the 4xs I have had, which happens to be a shitload. No problems, no issues..and most of the time is was basic gear oil and not the more expensive ones like Royal Purple...

[mattzj98]

It is recommended to run the LSD additive but like Pete said, people don't add them and nothing happens. I do just for the peace of mind

[Hypoid]

Nope, no additives with a locking differential. There might be a recommended weight, just read the destructions. :)

[Patrolman]

Nope, no additives with a locking differential. There might be a recommended weight, just read the destructions. :)

Ditto. The additive is only for an LSD.

[Java]

there's no clutch plates in a locker so you don't need the additive to increase friction. I run Detroit Truetracs which are technically limited slips but because they're gear based they don't need an additive. I remember when I put a Detroit Locker in the rear of my last Jeep the instructions said specifically not to use any additive or a synthetic lube, just plain old gear oil.

[Cr33p3r]

Thanks guys I just wanted to make sure after spending the money for the RP that it wasn't going to be wasted later next year when I get my lockers.

[jesse05lj]

It is a great thing to have all of these minds to pick!:)

[Cr33p3r]

Yes it is Jesse.

[mattzj98]

The oil itself just says "add to all LSD and locking differentials"

just throwing it out there. I know it's not needed lol