rear end gear fluid

**Zboner** · 02-09-2006, 12:37 PM

got a 2000 WS6 T/A

what is a deacent gear oil to run? how many quarts for the rear?

what mix also? like 80/90 or something?

what is a good additive for the posi?? how many bottle thingys will i need for that?

is Lucas ok?

**nytmare** · 02-09-2006, 04:04 PM

I'm doing a girdle and stud kit tomorrow and will be using Mobil 1, 75W90 with one 4oz bottle of GM LSD additive. I've read (using the search button on various LS1/FBody sites) that you'll use about a bottle and a half of gear oil.

Marc

**third_shift|studios** · 02-10-2006, 09:59 AM

joel, can you get that, hoss?

**BIG D's SS** · 02-10-2006, 10:10 AM

The easiest way is buy GM additive and buy 2 quarts of the gear lube that your running. Add the additive first and then add the gear lube till it starts to come out. Then you know it is full.

**third_shift|studios** · 02-10-2006, 10:16 AM

use the whole additive or just half?

**1fastcamarosss11** · 02-10-2006, 10:20 AM

i see that all makes sense.

**SteveC** · 02-10-2006, 10:33 AM

Use the entire bottle of additive, it is 4 or 6 oz.

Just to put some mess into the game, I run 85W/140 dino oil in my differential on my 01 Z28.

SteveC

**Transam388** · 02-10-2006, 10:45 AM

Royal Purple makes great stuff and I would highly recommend their gear oil. It aint cheap but it does a great job of reducing wear and friction!!

**third_shift|studios** · 02-10-2006, 11:55 AM

Originally Posted by SteveC

Use the entire bottle of additive, it is 4 or 6 oz.

Just to put some mess into the game, I run 85W/140 dino oil in my differential on my 01 Z28.

SteveC

define "mess"

**jimbo98z** · 02-10-2006, 03:55 PM

Originally Posted by Transam388

Royal Purple makes great stuff and I would highly recommend their gear oil. It aint cheap but it does a great job of reducing wear and friction!!

Agreed. Royal Purple is the balls

. I run their motor oil as well as their gear oil. I run 75w90 with the whole bottle of GM posi additive. Also, make sure you don't overfill the rearend. Fill till it starts coming out, then let it drain until it stops coming out. And make sure you're on a flat surface. Too much is actually a MUCH worse problem than too little in this case.

**Mr. Luos** · 02-10-2006, 04:33 PM

GM additive # 1052358
I have a bottle here waiting to get dropped in.

Royal Purple gear oil is a great choice.

**PaganEgyptian** · 02-10-2006, 04:35 PM

....Pennzoil Full Synthetic 75W90

and I dont use GM Limited slip with Brass clutches. -Tim

**SteveC** · 02-11-2006, 04:33 AM

Originally Posted by dipherentdesign

define "mess"

Controversy.

SteveC

**02z28ls1** · 02-12-2006, 06:57 AM

If I remember correctly in 99 they went to a torsen thextal (spl?)differential-a torque sensing job that doesn't use clutches in there to provide the limited slip part of it.I know my 98 required the additive and my 02 does not. Realizing this my be too late-if you put it in there don't worry about it-it won't hurt anything either to my knowledge.

**Sarge** · 02-12-2006, 07:24 AM

Royal Purple.....you lil shit....

**uwilluz** · 02-20-2006, 09:28 AM

if your using royal purple you must not be road racing the or have close to stock horsepower, because i cant keep the stuff from puking out all over the driveshaft and then being flung on to the exhaust.(nice smell) i never had this problem with the stock gm fluid. and will be going back to stock or trying out mobil one.

**keliente** · 02-21-2006, 06:13 PM

You guys are nuts with the synthetic/overpriced rear-end fluids.

It is not necessary to pay upwards of $10/qt for gear lube unless you are doing road racing where you would sustain 150mph+ for hours at a time, thus causing the fluid to boil.

I don't use anything but generic 80w90 on mine...it's not only daily driven, but takes a weekly thrashing at the track, usually 20 or more passes on 4,500k launches (M6).