Question about redline 75w90

[aquaman86]

anybody have any update on this? from all the searching i've done i still can't seem to come to a conclusion...

i have a '86 325es with a 2.93lsd and 5spd transmission. At first I was set on buying the cstrol syntrax LSD 75w-90 for the rear diff and then a regular synthetic 75w-90 (valvoline synpower 75w-90?). but based on more things i read the less clear it becomes...

for the 5 spd g260 transmission, would you recommend using the valvoline synthetic 75w-90 gear oil? but the bottle itself states it has lsd additives...

Here's the product description for the valvoline synpower 75w-90:

"Valvoline SynPower® Full Synthetic Gear Oil is formulated for ultimate protection and performance. A thermally stable, extreme-pressure gear lubricant, it is designed to operate and protect in both high and low extreme-temperature conditions. SynPower Gear Oil is specially recommended for limited-slip hypoid differentials and is compatible with conventional gear lubricants.
Maintains excellent low temperature fluid protection down to -50°F (-46°C)
Provides outstanding thermal stability for cleanliness and longer service life
Contains special additives to assist in protecting gear teeth from rust and corrosion and reduce chattering in limited-slip differentials
Recommended for (conventional and limited slip) manual transmissions where an API GL-5 or MT-1 fluid is specified"

[Herr Faust Schinken]

Not all do.

Buy lubro moly 75-90; no lsd additive unless you put it in

Gearboxes run 75-90 and do not want a lsd additive inside

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But don't 75-90 gl5 non LSD fluid normally tell you that they there not supposed to be used in LSDs

[Wanganstyle]

As far as I know all gl5 diff fluids have that additive already, unless it says on the bottle that its not for limited slips

Not all do.

Buy lubro moly 75-90; no lsd additive unless you put it in

Gearboxes run 75-90 and do not want a lsd additive inside

Sent from my GT-N7100 using Tapatalk 2

[jlevie]

Royal Purple. They Sponsor the NASA Spec E30 series. The majority of drivers won't put in their cars. They almost exclusively run Torco lubricants. Royal Purple does not have a very good rep to the more experienced.

To the best of my knowledge neither of those statements is true. Royal Purple isn't a national sponsor and most folks don't use Turco lubricants. I've not heard of anyone in the SE using that.

[RobertC]

Royal purple and Mobil one should both work fine

Mobil1 75/90LS (Limited Slip) wiped out my LSD in 4 months, not to mention the pinion bearings.

I ran for 4 years with plain old Castrol 75/90 and diff worked fine until I used the LS Mobil 1.

Royal Purple. They Sponsor the NASA Spec E30 series. The majority of drivers won't put in their cars. They almost exclusively run Torco lubricants. Royal Purple does not have a very good rep to the more experienced.

I agree with Wanganstyle, he explains it quite clearly. I would steer clear of the friction modifiers.

We run Torco SGO 75/90 in all the diffs, and RTF in the transmissions.

http://www.torcousa.com/products-auto-pro.html

If this is just a street car/daily driver. Just grab some good ol Valvoline 75/90 and fill the diff, about 2 qrts. You can also run it in the trans. 1.5qrts for the trans. (90-91 318is uses ATF in the transmission)

You can run a synthetic in both if you like, easier to pump in.

[Herr Faust Schinken]

Does it need additive?

As far as I know all gl5 diff fluids have that additive already, unless it says on the bottle that its not for limited slips

[Wanganstyle]

No additives needed at all

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[ky0u]

Does this: http://www.autozone.com/autozone/acc...fier=1437_0_0_

need additive or a stabilizer to work?

[ky0u]

Does it need additive?

[Herr Faust Schinken]

Royal purple and Mobil one should both work fine

[ky0u]

Are there any alternatives? I need to do the fluid change before this weekend and no store local to me carries redline.

Does this stuff work? http://www.autozone.com/autozone/acc...fier=1437_0_0_

[Herr Faust Schinken]

I've always read 75-90, for your transmission you need to check the sticker on the side

[ky0u]

Do our cars take 75w90 or 75w140? I read on another thread that it was supposed to be 140

[Herr Faust Schinken]

yeah just make sure its 75w-90 gl5 and not 75w-90 aka Mt-90 thats for manual transmissions

[Wanganstyle]

Redline 75w90 has the friction modifiers that a limited slip differential uses, 75w90NS does not have the friction modifiers.

LSD differentials do not NEED friction modifiers. Many people run WITHOUT them on purpose to have more aggressive lockup.

LSD friction modifier can be purchased alone in a small bottle from GM and added to standard 75-90 oil to save costs and fine tune the "slippage" in the LSD.

almost all e30's (80%+) with a used diff have marginal locking from worn internals; adding a specific LSD fluid to it will lower the Mu coefficient and decrease the performance of the already close to expired LSD unit.


for a E30 differential standard Conventional non-synthetic is just fine; replace it more often to keep particulate matter down.