Differential oil for Eunos Auto 1991

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: _Eunos Roadster
  2. I’m based near: __London
  3. I’m looking for technical help or recommendations on: __

Hi All,

I would be grateful if anyone could advise me on the best differential oil i should use for my Mk 1 Eunos Automatic. Not sure if i need LSD oil or not. One supplier said i need to provide my chassis no, is that correct?

Many thanks

Modassar

2

Widely available…

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Been through the same choice myself this week, I believe the GL5 spec is the important one to look for along with the 75/90 weight

4

Thank you for your reply, after i posted my question a mate (mechanic ) said i should put EP80/90 is this much different from what you put in your car?

Thanks

Modassar

5

Thank you for your reply, after i posted my question a mate (mechanic ) said i should use EP80/90, is this much different from what you have recommended?

Thanks

Modassar

6

It’s not hugely different, but seeing as you can get it from Halfords for about £13 semi-synthetic then I’d go with the 75/90. I use this stuff which is a little bit posher (fully synthetic) as my diff gets a bit more grief than most with the extra torque in my car: Differential LSD Oil, Fully Synthetic, 1 Ltr, All MX5 Models as I said I think the GL5 classification is important

7

Thanks Carl

8

Import Autos never had an LSD, viscous or mechanical.
If yours has one it’s been retro fitted.
Don’t waste money on fancy stuff.
Bog standard Castrol or REDLINE 75w 90 will be fine.
Cheap if you Google it.
Make sure the first nut you undo is refill one :wink: not the drainer.

1 Like
9

Yes mine is an import.

Many thanks.

Modassar

10

No that fine too, to spec GL5.
I was doubtful you had the LSD, the Castrol 75/90 oil linked to will suit either.
It’s what I’ve used on my 4 MX-5’s over the years each time I’ve changed the diff oil.:+1:

11

Hi Mick,

Just found out from Mazda Restorer Whom i purchased the differential from that it is LS they said they use 75w90 - GL4 is that ok? May i ask what the difference between GL4 and GL5 is?

Many thanks

Modassar

12

Hi,
Just found out from Mazda Restorer Whom i purchased the differential from that it is LS

Thanks

Modassar

13

Explanation below…

That’s why I use a different oil for my gear box, to GL4 spec.
GL4/GL5 oil spec suitable for the diff whether it be an LSD or not.

As explained in that link above it’s to do with the bronze (maybe brass?) parts in the gearbox where GL5 shouldn’t be used.

14

Thanks Mick

Much appreciated