Have you got a notchy gearbox!

[sinsin]

If u have a gen1 castrol have a fully synthetic called syntrans 75/85 , not cheap about $32 a liter , add some nulon G70 , will be like brand new.

I heard nulon is actually no good for our engines?

[chef]

I heard nulon is actually no good for our engines?

Not the 1 for engine, the 1 for box.

[GoonBong]

Is the Nulon additive safe where GL4 oil is specified like the Gen II?

[chef]

Is the Nulon additive safe where GL4 oil is specified like the Gen II?

Nulon adaditive I think can be mixed with any oils,. While its safe results are questionable.
alot of additive companies like slic 50 etc have been successfully sued by the United States government about claims etc.

[GoonBong]

I'm looking at the Penrite Pro Gear oil that Slixx mentioned in the Definitive Gearbox Oil thread as the Castrol Syntrans I have in now is great when warmed up, but still a bit gnashy when cold. I'll go easy with the additive when I swap out the oil with the Penrite and see how I go.

[slixx]

I'm looking at the Penrite Pro Gear oil that Slixx mentioned in the Definitive Gearbox Oil thread as the Castrol Syntrans I have in now is great when warmed up, but still a bit gnashy when cold. I'll go easy with the additive when I swap out the oil with the Penrite and see how I go.

Like I mentioned in previous posts, the Penrite is awesome when warmed, but still a bit notchy downshifting into 2 or 1, but after 4-5 shifts its upwards from there

Guessing it'll be better in the summer time


Peter "SLIXX"

[GoonBong]

No worries Slixx. It's been nearly 40,000kms since the gearbox oil was last dropped so it's probably a good time to do it anyway. I think it could be neck and neck between the Castrol Syntrans and the Penrite Pro Gear for the best oil possible for Gen IIs.

[slixx]

No worries Slixx. It's been nearly 40,000kms since the gearbox oil was last dropped so it's probably a good time to do it anyway. I think it could be neck and neck between the Castrol Syntrans and the Penrite Pro Gear for the best oil possible for Gen IIs.

Well lemme know how you go @GoonBong
My Mazda dealership always likes updates on real-world trailing


Peter "SLIXX"

[GoonBong]

For sure. Once it's in and been running for a while ill drop you a line.

[sinsin]

No worries Slixx. It's been nearly 40,000kms since the gearbox oil was last dropped so it's probably a good time to do it anyway. I think it could be neck and neck between the Castrol Syntrans and the Penrite Pro Gear for the best oil possible for Gen IIs.

You say GenII, isn't it the same for GenI's?

[GoonBong]

Pretty sure Gen I's spec GL5. Gen II's can't use GL5 because the yellow metals in the syncros get corroded by the sulfur, or something.

[chef]

Pretty sure Gen I's spec GL5. Gen II's can't use GL5 because the yellow metals in the syncros get corroded by the sulfur, or something.

Think u find its the other way round. Gen1 isGL4

[chef]

When I first read this thread I thought it said have you got an itchy gearbox

[GoonBong]

Think u find its the other way round. Gen1 isGL4

Just checked the manual for my Gen II. It's GL4.

Edit - think you're probably right about GL4 oils being good for Gen I's. Not sure where I read that GL5 was the right type...

[sinsin]

Think I've got some searching to do about it
mine's a GenI

[chef]

Think I've got some searching to do about it
mine's a GenI

Mines a Gen 1 and like castrol syntrans fully synthetic it's reconvened for Gen1 on castrol website.

[KFuNk]

Think I've got some searching to do about it
mine's a GenI

In gearbox oil thread I'm running Castrol VMX 75w80. Runs perfectly in the cold and even better when hot.

[chef]

In gearbox oil thread I'm running Castrol VMX 75w80. Runs perfectly in the cold and even better when hot.

On castrol website VMX is only recommended for GEN2 , Gen1 is VMX-M

[KFuNk]

Well possibly I got it done when I got my 120k service. From experience and 30k Kms later i have smooth gear changes on my Gen I.

[slixx]

In gearbox oil thread I'm running Castrol VMX 75w80. Runs perfectly in the cold and even better when hot.

The last time I went to my Mazda Dealer, they have a whitepaper on VMX-80 and not to be used in GenIIs anymore

They will use a 75w85 now


Peter "SLIXX"