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Gen 2 - Alternative Manual Transmission Fluid

17465 Views 42 Replies 9 Participants Last post by  mazda626awd
This is a bit of a sound-off thread. Got my car back after a harrowing experience in a gen1 mazda3 (this hooptie made my old SL1 look like it was loaded with features) . . . After $112 a lighter wallet I got:

What I want to know is this:
What alternative fluid have you tried in your gen 2?

Also, please note if you were trying to remedy any particular problem.

I'll start:
very hard to get into gear below 40 degrees F -- changed to RedLine MT-90 (Synthetic 75W-90; GL-4) at 25k miles

Nicer than stock for the first 3k, after that, about as good as stock, occasionally have 2nd gear 'bouncing' when I try to shift.

Brought it into the dealer at 41k miles . . . can't reproduce.

I'm curious if anyone's gone down to something like 70W-90 or even 80/85. I don't live anywhere even REMOTELY cold, but it seems (to me) from the complaints of others about the same thing that this wasn't tested anywhere outside of Virginia, Cali or Arizona.

I'm considering Amsoil (within owner's manual specs) first, then possibly considering Royal Purple, which someone said wasn't good for Mazda's about another vehicle.

Anyone tried RedLine MTL? Seems sort of extreme, or even possibly Smurf's Blood . . . their high-shock gear fluid.


I'm considering (at this point) writing Corporate for a refund on my extended warranty; it seems like . . . if it isn't something my wife and two of my non-gearhead co-workers would notice AND something that could be fixed by Midas, the dealerships aren't prepared to deal with it . . .

Sound off Gen2 M/T owners :)

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I read this thread a couple weeks ago but couldn't respond til now. I bought a 2010 Mazda 6i with the 2.5 and MT on the 5th of July. Love the car but noticed a grind occasionally when shifting 1-2 and the whole shift mechanism feels rather clunky. I own 5 Mazda 626s all with MT (2) 89s and (3) 91s, One of each year is on the road. The others are for back up and parts. Anyway they all use Dexron as a manual trans fluid. When did that idea change. I used slick 50 plus the Dexron when I worked on them at some point. I don't know if it would make a difference on the M6 since the Trans is a whole different mfg. Besides the shift problem I am getting a vibration between 1800 to 2100 RPM. Above and below it runs smooth. Since I bought the car from CarMax and its on the 30 day warranty, I took it back yesterday and they sent it to a Mazda Dealer in Richmond. The technician at CarMax agrees with me there is a problem and while I was there pulled up a page that included both M6s and Fusions. The grinding problem showed up and supposedly is linked to coasting. In order to increase gas economy, using the clutch or even shifting into neutral to save fuel causes a problem with the synchros. The other issue I have with this car in stock form is my 626 with the 2.2 and advertised 110 hp @ 4700/130 torque @3000 has more seat of the pants Zoom than this 170 hp @ 6000 rpm and 170 torque @ 4000 rpm. The power band is wrong and the close gear ratios are useless. Don't get me wrong, I do like the car but what was Mazda thinking in the design room. I rented a 2012 M6 with auto trans and @ 2000 rpm, I was doing 60 MPH. in this M6 w/ MT I got 45 MPH at 2000 rpm. Go figure. The problem with the AT is it downshifts too easy wasting gas.
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Gearing is definitely designed for people that don't know how to shift. For the 2009+ (Not sure about 2013 and 2012), 5th and 3rd seem to exist as engine breaking gears for me.
2000-2200rpm is suitable for driving where it doesn't lug; 3000+ the car is plenty frisky.

If I come up with another problem, I'm going to get suspicious, because using the clutch is what you're SUPPOSED to do.

At any rate, I find that used manuals tend to have had pretty poor previous owners with regard to maintenance and just not shifting right . . .
Ernie I agree about the gearing. I generally use Ist, 2nd, 4th and 6th during normal acceleration than 5th and 3rd during deceleration. I'm going to update my experience with the warranty in the 2011 transmission failure thread. It really dissapoints me the excuses they give to keep from spending time on the warranty work.

Dave in VA.
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