NB8B gearbox oil

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Regie
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NB8B gearbox oil

Postby Regie » Wed Apr 29, 2009 5:06 pm

i have some full synthetic gearbox oil sitting here ready to be poured in.

Now do i have to take the brace off that sits under the gearbox?

also im assumiming that there is a fill and drain plug on the side of the box?

thanks
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NB8B gearbox oil

Postby Fuzzlet » Wed Apr 29, 2009 5:46 pm

check out http://www.miata.net/garage for info...what oil are you gonna use?
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Regie
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NB8B gearbox oil

Postby Regie » Wed Apr 29, 2009 7:20 pm

i got Penrite full synthetic stuff. (cant remember the number)

but it was $55 for 2.5l
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16bit
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NB8B gearbox oil

Postby 16bit » Wed Apr 29, 2009 8:44 pm

thats a good deal. i payed 60 bucks for 2L of castrol syntrans 75w 85 something something stuff.
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Regie
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NB8B gearbox oil

Postby Regie » Wed Apr 29, 2009 9:00 pm

yeah i think its called Penrite Syn75.... that rings a bell. Just got it from the local parts shop...

its going to be like a new car when the oil is changed! woo!

great guide there thanks Pete
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wun911
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NB8B gearbox oil

Postby wun911 » Wed Apr 29, 2009 11:37 pm

There is one bolt on the 6spd box you can't undo. It holds your 6th and Reverse.

Its kinda easy to figure out and do though.
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NB8B gearbox oil

Postby Garry » Thu Apr 30, 2009 9:48 am

Dont undo any bolts on the drivers side of the NB8B gearbox on a right hand drive car. The fill plug is on the passengers side near the exhaust.
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madboy
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NB8B gearbox oil

Postby madboy » Thu Apr 30, 2009 10:02 am

Regie wrote:i got Penrite full synthetic stuff. (cant remember the number)

but it was $55 for 2.5l


My local Cheapa Auto Parts sells that for less than $50, I have a 2.5lt bottle in the boot waiting to poured in too. I prefer to get my auto gear from cheapa, you get more personal service from them(no pimple face teenagers with no clues) and they are generally they are cheaper than Ricebarn and on par with Supacheap

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Hellmun
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NB8B gearbox oil

Postby Hellmun » Thu Apr 30, 2009 12:09 pm

My gearbox was really notchy with the Penrite Sin 75 gear oil, after less than 1000km's I dumped it out and put Redline in. That made it significantly smoother between shifts. Redline was really expensive though..think $115 for 3.75 litres.

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Regie
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NB8B gearbox oil

Postby Regie » Thu Apr 30, 2009 12:11 pm

Hellmun wrote:My gearbox was really notchy with the Penrite Sin 75 gear oil, after less than 1000km's I dumped it out and put Redline in. That made it significantly smoother between shifts. Redline was really expensive though..think $115 for 3.75 litres.


it may need 1000kms or so to work its way through the gears though
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NB8B gearbox oil

Postby Okibi » Thu Apr 30, 2009 1:18 pm

Garry wrote:Dont undo any bolts on the drivers side of the NB8B gearbox on a right hand drive car. The fill plug is on the passengers side near the exhaust.


VERY good advice ... a few people have undone the wrong bolt and killed reverse gear.

Also ..

Always loosen the filler bolt before the drain bolt. (this way if the filler bolt is jammed tight your car isn't stuck with no oil in the box and no way to refill it).

Always use a new crush water, I get a stack of them from Mazda they cost bugger all.
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NB8B gearbox oil

Postby wun911 » Thu Apr 30, 2009 1:40 pm

I think the service manual says to change it every 70,000 km.
In that time the oil goes a very dark brown colour (MT 90 starts off golden).
In 70,000 km I usually go though one of the shift boots.
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