brother's '99 Boxster base 5 speed

[dailydriver]

Is the Motul gear 300 75W-90 NON limited slip safe/good to use in the Boxster's transaxle??

I want to use this over the Red Line 75W-90 NS because of the Motul's MUCH higher V.I. (222!!), and that it might be even less shear-prone than the (yes great nonetheless) RL product.
(He drives this car every day, right through the coldest winters.)

Once I change this, he will probably NEVER do it again as long as he owns the car, so the fluid's longevity DOES matter, the way he abuses/does NOT maintain his cars.

Amsoil and others do NOT offer a non-friction modified synthetic 75W-90 gear oil, so the choice is limited anyway.

(Amsoil does not even list an app for this car, due to the fact that even the models WITH a limited slip transaxle REQUIRE a non-friction modified fluid, despite it being a clutch plate type diff from the factory.)

 

[Greasymechtech]

Ford 75w90 GL5 link

Redline 75w90NS

Motul Gear 300

Eneos GL5 75w90 Non-lsd

Torco SGO non-LSD 75w90

Subaru


Regardless of the fluid you choose, you'll be changing it again if brother doesn't like the shift quality. Coin toss among the GL5 non-LS fluids. Good luck!

 

[donnyj08]

Your Local Ford dealer should have the MC 75w90 in stock. It is pretty good stuff.

 

[CT8]

-What makes the VI higher? The base oils or VI improvers?

 

[DeepFriar]

Gear 300 is full synthetic so the VI is probably built in via the base stock. Should work fine in the Boxter.

 

[splinter]

Originally Posted By: dailydriver
Once I change this, he will probably NEVER do it again as long as he owns the car...

Yikes. Not the typical new OCD Porsche pilot.

SwepCo is popular with my Porsche friends.

www.swepcolube.com

 

[dailydriver]

Originally Posted By: splinter
Originally Posted By: dailydriver
Once I change this, he will probably NEVER do it again as long as he owns the car...

Yikes. Not the typical new OCD Porsche pilot.


NO, he is most definitely NOT the 'typical' P-car owner!!

I just changed the plugs for him, and told him to get one of the NGK/Denso 100K mile Iridium variants (Laser/Long Life) since he neglects this car habitually. He showed up with the Denso Iridium Powers, at best a 40K mile plug, correct?

So I installed them along with new plug well tubes and seals/o rings, to the correct torque spec.

The Beru double ground electrode copper plugs I removed had OVER 145K miles on them, were setting misfire codes (and of course the dash light) on ALL cylinders.
The center electrodes were worn thinner than the O.4 mm center electrode diameter ones on the new Densos, having started life at ~2.5 mm!!!!
The car was barely starting/running before the plug change, but he probably would not have even done this IF he did not HAVE TO in order to pass the state emissions inspection.
Just like he would not fix his brakes if the state did not demand it.
He drives around in ghetto fashion with his rear plastic window all taped up from the MANY large rips, tears and cracks in it.
Any true Porschephile would CRINGE and recoil in disgust if they saw just how badly this poor thing is (NOT) maintained.

I don't think it has EVER been polished/waxed since he's owned it (2002).

 

[dailydriver]

Originally Posted By: DeepFriar
Gear 300 is full synthetic so the VI is probably built in via the base stock. Should work fine in the Boxter.


Yes, and it might be an even higher group 5/POE content than the Red Line.

 

[dailydriver]

Originally Posted By: Greasymechtech
Ford 75w90 GL5 link

Redline 75w90NS

Motul Gear 300

Eneos GL5 75w90 Non-lsd

Torco SGO non-LSD 75w90

Subaru


Regardless of the fluid you choose, you'll be changing it again if brother doesn't like the shift quality. Coin toss among the GL5 non-LS fluids. Good luck!



There is also a Millers non limited slip, CRX 75W-90 NT GL5, but that makes the Motul seem inexpensive.