z-ya

iTrader: (1)

Richmond 85/140 gl6 synthetic.

INMY01TA

iTrader: (1)

I use any dino 80/90 gear oil. Neither Moser nor Strange recommend syn. gear oil for their Eaton posi's, nor Auburn for theirs. It's simply not needed.

stinkfinger

7,500 or 75,000?

black00TA

iTrader: (3)

7,500

Yep.

Matt D

iTrader: (49)

Royal Purple 85w140

BORN2LOSE

What if you don't add it? I heard both sides on this issue so which is correct? I didn't add any to mine when I changed it this summer.

black00TA

iTrader: (3)

ive also heard mixed reviews, i wont take the chance.

i know the torsen dif calls for posi additive. im pretty sure the SS has the auburn if im correct, i dont own an auburn so i couldnt tell ya FOR SURE on that one.

Matt D

iTrader: (49)

Most synthetics have the posi additive already in it. I know the RP 85w140 does.

golfer2410

I just switched over to Amsoil when i got my 3.73s in october, its a great oil.

OctaneZ28

iTrader: (6)

I'm doin a swap next weekend, and planning on using Royal Purple 85w140

Silver SS in Germany

AMSOIL 75w90

dailydriver

Technically the Torsen type diffs (T2, T2R, Tru Track) do not need any friction modifier additive (even though GM says to add it, possibly to help quiet the coast down, muted "marbles in a coffee can" noise Torsens are infamous for, but a heavier gear oil might do a better job at this). Auburns, Eatons and all other friction type "clutch pack" diffs must use one of the friction mod additives, as well as only non-synthetic, petroleum based gear oils.

Viper

iTrader: (6)

If you have the T2R, use the 75w90 with no friction adder. Sam Strano advice. I don't know about the others. Don't use 85w140 with the T2R.

bigdsz

iTrader: (1)

Don' laugh, but Walmart 85W140 Synthetic in my 9". It's a good product and cheap. I refuse to pay $13-$15 a quart for Mobil 1 or Redline, it's bad enough that I pay $5 a quart for Mobil 1 motor oil.

chicane

You didnt specify on use.

Engine = Mobile1 or RedLine
Transmission (M6) = Redline ATF with 1qt of MTL
Differential = Torco, Almasol or Amsoil. (~Straight 140wt only~)
Powersteering = Redline (~only~)

dailydriver

If you had a diff that forbade the use of synthetics, would you use the Torco RGO, Lucas petroleum, or the Lakewood BFL?? Have you actually used the D4/MTL combo in your T56, and if so what year and for how long??

Sgt. Spuds

iTrader: (1)

What should I be using on a 137k mile stock 10 bolt? lol

I drive pretty hard. six speed

chicane

Ahhhhh.... that is a totally different subject. I myself do not use synthetics in differentials at all. But from the choices you have listed, most likely the Torco. The Lucas in a very close second. In my opinion however, I myself would use a suspended moly #209 straight 140wt from Schaffer oil products and add 1 (one) 4oz bottle of Ford friction modifier, as it to is parifin based, which will homogenize perfectly.

Second question. Yes. I dont actually understand the relevance to what year the vehicle and/or tranmission is. A T-56 is a T-56...... is a T-56. My chassis is actually a 1967. I did however, start using that formulation somewhere back in 92-93 (uhm, yeah.... 1992) when we were running the very same transmission in the Challenge Series classes. The T-56 was later released in the production 93 platform.

The MTL is merely added to aid in shifting, as it takes away some of the 'notchiness' in performance built T-56 transmissions.

Spuds~ I would use a straight 140wt, non-synthetic.

Sgt. Spuds

iTrader: (1)

So what brand of 140wt non-snythetic do you think I should use? Something that I can get localy. Also, what additives do I need? Why not synthetic?

Thanks for all the help.

MetallicaMatt

iTrader: (19)

i bought the synthetic RP, but Currie just told me use the Dino

any problems with this?

has a locker also...