Time for an oil change. I have been running Redline Lightweight Shockproof in the tranny and Redline 75w90 in my 2 way diff (maruha).

Thinking of going to Motul Gear 300 for the tranny and Motul 90PA for the diff. Thoughts? I can get these dirt cheap through my work and they seem to be solid oils from what I've read online.

What do you run, what do you like, what have you had issues with? etc...

 

AMSoil MTG GL4 75w90 in the tranny. Crisp, lightning fast shifts hot and cold. I use Shockproof in the diff to help with the shock loading it sees from IR wheelspin.

Before the AMSoil I ran Redline MT-90 in the tranny - that was fine as well.

 

Can we also talk price / location too.

I have cheapo gear oil in my diff right now and mobil 1 synth in my 6spd (advanced auto). the 6spd isnt happy when its cold. I will be changing ALL my fluids in the spring when it goes back on the road/track

 

I don't have much to add, but got a lot out of this thread.
https://www.miataturbo.net/showthrea...ansmission+oil

 

Got a tip here about the Motorcraft MTX-75 IB5 oil for my tranny, and I started using it after my turbo conversion late summer last year.
My issues with shifting on high revs are gone, even after installing a short throw shifter.

The cold doesn't make it useless either, and it's been down to -20c here the last month. That's -4 Fahrenheit btw..
If the car starts, the tranny works like a charm.

Edit: What tranny do you have? Seems to be a big difference in opinion when it comes to 5-speed and 6-speed users. For the record, I'm using it on a 5-speed.

 

In a tight, I had Mobile 1 in the tranny (5 speed). Worthless shifting.

You will not believe the difference when you use the right oil.

 

I'm another disappointed soul who used Mobile 1 - cold shifting is absolute rubbish. I'll be replacing it when the tranny is out this spring.

-Zach

 

redundant thread is redundant

 

We have an amsoil dealer on the forum who sells at cost to members. PM me and I will give out his email.

 

Amsoil MTG 75W90 for the Tranny. Works noticeably better than anything else I have tried.

Bob

 

I just ordered up some Gear 300 for $12/L. Going to try PA90 in my diff for $8/L. If I don't like it, what's the worst that can happen?

 

running MT90 in my trans and kaaz lsd oil in the diff. car is smoov.

 

My DSM (front wheel drive, KAAZ LSD) seems to really love the cheap motomaster synthetic GL-4 + the motomaster LSD additive. Anything else in the gearbox and the LSD is noisy as all hell when I turn. I change the trans fluid with every oil change (approx. every 5000KM) since KAAZ says to change it every 3k.

In the GTR I've been running redline shockproof heavy in the trans to keep it alive and RP 75-90 in the diff to keep it cool. I've had no problems with either, but when I was running RP in the trans I broke one. I don't think the oil was a problem but the shockproof heavy sure is heavy, and seems to protect stuff better.

 

oops. 30k is probably fine, right?

 

LOL

it probably is, I do it every 5k with no problems. seems paranoid to me when most people just never change it ever. If it's noisy, it's probably time to change the fluid.

 

We ran heavy shockproof in my buddies 530AWHP GTR without issues. No broken trannies.

I have the light stuff in the Miata right now and it's o.k...

 

In the transmission I have tried Mobil 1 gear oil, Royal Purple Max Gear, and the Motorcraft Full Synth gear lube XT-M5-QS. So far the Motorcraft is by far the best. It definitely improved shifting. Mobil 1 was ehhhh and Royal Purple Max-Queer was terrible.

I have read good things about the AMSoil as well.

 

5 or 6 spd?

 

A Mazda GTR or Nissan GTR? I've been thinking of using the heavy shockproof in my GTX but I feel like it might be overkill.

 

there's mazda GTR's?

I know some JDM FC's came in a GTR trim level but they're pretty rare birds.

anyways I was talking about my '92 R32 GTR, falcon's on the GTR board too.