Which tranny and LSD oil?

[oscar35783]

I'm looking to change my tranny oil and LSD oil and I want to use Royal Purple. but i'm confused which Royal Purple is for tranny and whic one is for the LSD. By the way i drive a 1991 Supra Turbo. Do i need to add any additives to the Royal Purple for the slip? Thanks

 

[TurboSupra7]

I just did the LSD oil about a week ago on my car, and I highly recommend it. I used Royal Purple Maxgear 70w90. It already contains LSD additives so you don't have to add any thing special. I believe that same oil works great in the tranny as well.

 

[jetjock]

The use of friction modifiers in manual transmissions is not recommended.

 

[oscar35783]

So it's the Royal Purple max gear for the tranny and LSD? I believed my car has the Toyota fluid from the previous owner. It has the typical 1-3 gear hard to shift when it cold but better when the car is warm. I hope the RP will fix that problem. Thanks for the replies.

 

[jetjock]

As I said, using a lubricant designed for LSDs with friction modifiers in manual transmissions is not recommended. Hampers synchro engagement. It's your car though

 

[oscar35783]

What type and grade of oil are u using for your 5 speed turbo trann and LSD?

 

[Piratetip]

Look up OEM specs. Go with that.

 

[jetjock]

I agree with Piratetip. That said, I run Red Line MTL in the tranny and when I had the LSD ran either Toyo fluid in the pumpkin or RL gear oil and added the FoMoCo modifier to taste. Other options are possible, such as MT-90 in the tranny. I'm not all that familar with RP products so you might want to check with them. It's just that the synchros in your tranny will work best when the right oil is used and LSD oils with modifiers usually hamper their operation. Whatever you use in the rear end be sure to change it once in a while. There isn't much in there and it takes a beating.

 

[oscar35783]

Thanks for the replies, where can i can get my hand on some Redline MTL and MT-90. Does the Local Auto part store has it or do i need to order it from Summit Racing?

 

[jetjock]

Check out Red Lines website for distributors and tech info. I'll bet there is someone near you who retails the stuff but you can get it many places online. Summit is as good a choice as any I suppose. I'd go with MTL but it's your call. You can use their gear oil in the rear end too, just be sure you either get the stuff with friction modifiers in it or you can use the non modified stuff and blend it with the Ford modifier. I'd still check RP's website though, they may have something. As a half assed tribologist I personally tend to choose lubricants based less on hype and more on science.

 

[isnms]

Redline MT-90, transmission, wo/friction modifier, meets OEM 75W90 GL-4 specification
http://www.redlineoil.com/products_gearlubricants.asp?pvID=74&prodID=57&subcatID=18

Redline 75W90, differential, includes friction modifier, meets OEM API GL-5 specification
http://www.redlineoil.com/products_gearlubricants.asp?pvID=81&prodID=60&subcatID=20

 

[isnms]

FYI

http://www.brandwood.net/supra/handbook/8/service.html

MANUAL TRANSMISSION
Oil Capacity L (qt, Imp qt)
7M-GE 2.4( 2.5,2.1 )
7M-GTE 3.0( 3.2,2.6 )

Oil Type:
Multipurpose gear oil API GL-4 or GL-5

Recommended Viscosity
7M-GE
SAE 80W, 80W-90 or 75W-90
7M-GTE
SAE 75W-90


DIFFERENTIAL
Oil Capacity L (qt, Imp qt):
1.3 ( 1.4, 1.1 )

Oil Type :
Hypoid Gear Oil for Limited Slip Differential API GL-5

Recommended Viscosity
below -18°C SAE 80W or 80W-90
above -18°C SAE 90