i'm replacing my tranny oil and rear-end oil and i need to know how much to buy and what weight to buy, please help with info!...

thanx

 

What kind and what year car?

 

if you want to go with redline there isn't too much selection AFAIK

http://myoilshop.com

your choices are:

redline MT-90
redline MTL

both $7 a bottle.

 

Use MT-90 for the tranny, 75w90 for the differential

 

my car's a 1989 S5 RX7 GTX....

if that changes anything....

and how many litres of each do i need....

 

manual tranny= 2.6 Qts
diff= 1.3 Qts

 

so late and now i feel so stupid....

so:

-3litres for the tranny
-2litres for the diff

and i should be ok?...

 

so....


Shopping list:

Tranny:
3litres of Redline MT-90

Differental:
2litres Redline 75W90


Correct...?

 

Yes.

I use MTL for my tranny. Seems about the same to me.

 

so there's no difference between MTL and MT?...

what are the differences though....

 

Same here..I used 3 full quarts. in the trans. And for the Diff. I'm using Royal Purple 75-90 with the LSD Additive (I used 2 full quarts).

 

For the differential (mine is LSD) I used Redline Super Light Shockproof with Redline LSD additive.

MT90 for tranny.

 

whats the LSD additive good for?...

my car has LSD aswell.... so whats best additive for diff?...

 

Without the LSD additive an LSD differential will chatter when starting off from a stop when using the Super Light Shockproof. Don't know about other "normal" oils for the diff like just straight 75w90, but I'd assume you'd still want to use it.

This is what Mazdatrix says about the LSD additive they sell, which is a GM product.

"If this type of additive is not used with the rear end oil, normally you get a "chatter" from the rear axle when starting from a stop, and turning at the same time. This is due to the clutches in the diff. locking and un-locking. One container/part number needed per rear end oil change."

 

so....

should i just use redline 75W90 or would it be best to use the super light shockproof with additive....

i will be racing the car at the strip fairly often and i want something that will protect me a little more for 5000rpm clutch bombs....

 

Super Light Shockproof will have less loss through the drivetrain than the normal 75w90, so my personal opinion is to use it with the additive, but that's me.

 

but which is better for bombing....

oh god that sounded bad, lemme rephrase....

which would give my rear diff more protection from me beating on it....

 

The shockproof with the proper additive should be just fine, I beat on mine regularly. However let me tell you this. When you start doing 7k clutch DROPS at the drag strip and then flooring it and having the most violent wheel hop and spin you've ever seen like me, the N/A LSD will eventually start to go out like mine is

But I think that's true no matter what oil you're using in it heh. My backlash is totally messed up and it seems like the bearings are going out, but oh well easy enough fix once I have time to pull it and take it apart. And my LSD has 160k miles on it too.

 

yeah true, i just dont wana break something when i lower my tire pressure too 16psi and bomb it at 5000rpm....

so whats the additive called?, is it made by redline?...

and the oil is called redline shock proof?...

whats the difference in thickness between the 2?...

 

Redline calls it a "Friction Modifier" http://www.247-parts.com/item.wws?sku=RLGFM

"DIFFERENTIAL FRICTION MODIFIER & BREAK-IN ADDITIVE: is a friction modifier designed to reduce limited-slip noise and to aid the proper break-in of any differential. This can be added to any gear oil to reduce temperature during break-in and prevent gear softening. Replaces manufacturers' limited-slip additives. Can be used to perfectly tune a limited-slip unit. Red Line 75W90 and 80W140 Gear Oils already contain this additive. "

So if you use the 75W90 you don't need that, just if you're using the shockproof oils. Also you can get an LSD additive at a GM dealership, that's the one Mazdatrix sells. I used that at one point and it made the chatter go away completely and worked great. Right now I'm using the redline one with no chatter as well.

Thickness? Not sure, but here's the link for the super light shockproof oil http://www.247-parts.com/item.wws?sku=RLGSS

I learned about the super light shockproof oil from Icemark, he said he's used it in all of his differentials (or maybe just LSD's, can't remember) with great success.

 

very very interesting....

i'm sure i cant go wrong either way....

i just want something that will give me the extra little bit of protection, because the last thing i want is a blown diff....

how would you mix that additive in with the shock proof oil?...

 

The way I mixed the additive in was i squeezed the entire contents of the additive into the first bottle of the diff oil, shook it up to get it mixed, then put that into the already emptied differential. Then I took my 2nd bottle of the oil to top off what was needed (with no additive in that bottle). From what I remember reading on the directions 1 bottle of the additive is sufficient.

 

hmm, very interesting....

yeah mabe thats what was making me worried yesterday, when starting off the diff. would chatter a bit, i assume this is normal...?

 

Well, mine did the same thing before I put in the additive. After the additive it went away completely.

 

right on, i'm gunna go too the local performance shop and get some, i made the shopping list and all, hopefully i dont have to give a limb for these items....

anything else i should get/change in my car while i'm at it that you would suggest?...

i was thinking some watter-wetter....

do you think at 16psi in the rear tires i'd be damaging anything when i drag?...