Rear end help

[ndmick]

I bought a 1997 Camaro Z-28 SS about 2 months ago 383 engine ,moser rear end 373 gears (I think),6 speed 116000 miles on car around 10000 on drivetrain.The guy I bought it from bought it new,but about 4 yrs ago he put a Jasper 383(runs real good for what it is)rebuilt T-56 by jasper also.My problem is he hired all the work done and I can`t find the people who did the work.He says its a Moser 9" in the car the reciept only says replace rear end assembly, assemble and reinstall axles -press bearings,he says it has 3:73 gears but doesn`t know any more.So what lube to put in it ? thats my question.I`m trying to change all the lubes before putting many miles on it. The reciept also states install torque arm relocation kit aluminun carolina drive shaft.He spent a pile of money on mods I mean A PILE OF MONEY.This car runs great in like new condition everything works.Its a nice car.
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[daytonablues]

If i were you, to be on the safe side, i would use any synthetic 75w-90 or 80w-90 gear oil and GM limited slip additive. (something like castrol, valvoline, etc and the additive you get at the dealer).
im saying this cause with the 9 inch you cant just pull the diff cover to see what kinda limited slip is in there, a gear type or one that uses clutches like an auburn. probably you have a locker type posi in there like a Tru Trac. Since u can use synthetic diff oil in pretty much any diff if your unsure of whats in there you should be fine. but DEFINITLY use the friction modifier just in case you have a limited slip that uses clutches not gears.