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Discussion Starter · #1 ·
I cant believe this has not come up B4 but I cant find any thing on a search..
what should I be putting in a 5 speed .. I would like to use a synthetic (such as redline).. but what viscosity should it be?..
I use redline MT90 in my second gen and it is spot on .. but is the same true for the first gen?
does any one know?
 

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I believe the manual calls for 75w90
 

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Discussion Starter · #3 ·
Even if I go fully synthetic..? the box is a bit notchy and im hoping to smooth it out a bit..
 

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Discussion Starter · #4 ·
Oh ! and how much does it require (if you know)
 

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3.65 litres.

Fully synthetic will help to keep the heat away from the diff gears.

Has the clutch been upgraded. More pressure ?
 

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Discussion Starter · #7 ·
As far a s I know it is just the stock clutch . It doesn’t feel too bad but not particularly grippy/hard..
I’ll get some tomorrow thanks for all that..
 

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On the US and Canada spec cars, there is a sticker on the underside of the hood that lists all of the fluid specifications. I would think yours probably has this as well.
 

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Discussion Starter · #9 · (Edited)
Aw yea I knew the recommended oil by Mazda, but not what the people that really know the cars, and drive tham after 10+ years think (Us). A-la .. the redline MT 90 in the second gens.. not what is recomended but works best..

I think the problem im experiencing with the selector may be something in the linkage as it is stiff to push to the side (first/second) and it doesn’t return to the center when replaced,
But ill drop the oil as well and have alook at the selector linkage when im under there tomorrow.. thanks again..
 

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I've had regular vegetable oil in mine for a year, no problems. I mean, c'mon, it's all oil, right? And it's a fraction of the cost.

:rolleyes: Just kidding. I have Amsoil gear lube in it. I forget the weight (I'll try to remember to check when I get home). Dunno if it's available in Australia though, so probably whatever good synthetic you do have available.

No, I didn't notice a difference, but I had no problems with it either before or after switching.
 

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The current box that is in mine now, has the pin that goes thru the selector plate ( "H" plate) broken off.

Now the prob that it causes, i am able to grab 1st while still in 3rd.

The gearbox locks up and the car will rock on its mounts. NOT GOOD.

It only happens when i downchange from 3rd to 1st, skipping 2nd.




As for the clutch side of things. I have reduced my clutch slave cylinder bore dia (smaller resleave fitted). The reason for this is to make the pushrod for the clutch travel further.
When i put in a heavier pressure plate (2500 lb), the clutch wouldn't engage right. As it wasn't travelling out as far as it needed to.
 

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Ok, just got home, grabbed the bottle to check the weight.

80W-90 Gear Lube. Don't remember the price. Yes, probably more than regular. Probably less than Red Line. Only place I know to get it is online.
 

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The first gen is just like the 2nd gen manual. Use the redline MTL or MT90 (the ones that are ok for brass). Use of standard gear lube will pit and break down the brass syncros and lead to accelerated wear of the tranny. If you don't use the MTL or other synthetic (NOT MOBIL GEAR LUBE) that is safe use the auto tranny fluid like is recommended by Mazda/Ford.
 

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Discussion Starter · #14 ·
The dam 3inch exhaust was clashing with the selector.. all sorted now and with new oil to boot .. so thanks again..

 

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Hey, mr.mx6, is that downpipe 3"? It looks more like 2-1/2" I was just wondering if it was a size in between.
 

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Discussion Starter · #17 ·
Mate I don’t know it could be ill have to measure it.. (I didn’t install it) I just assumed it was 3 inch. Looks big.. lol
 
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