2004 Mazda 6 - MTX Transmission

[jbedford]

Hi everyone,

New to the forum here.

I drive a 2004 Mazda 6 V6-GT with a manual transmission. The clutch was replaced at 60,000 KM under warranty due to a clutch shudder Mazda recall. I'm not at 93,000 KM, and want to change the transmission fluid.

I live just east of Toronto, and the winters in Canada get quite cold. The transmission is difficult to shift until the transmission warms up.

In the summer, under hard acceleration, the shifter is notchy.

What does everyone recommend?

The guys at Mazda6club.com seem to really like Redline MT-90 for their cars.

How does everyone rate the Redline product.

Reading this forum, I also see that others like Royal Purple, and Amsoil.

What is my best bet to smooth out the shifts?

Thanks!



Jason

 

[Big Jim]

You are on the right track. A synthetic fluid may help the cold shifting.

Personally, I'm partial to Torco.

 

[Pablo]

You can use a GL-4 or GL-5 in there.

IMHPO - Mazda has some tricky MT's. Fluid choice can help - but must be dictated by personal feel, climate and some knowledge of wear prevention.

Professionally I say you should stay away from GL-5 differential type oils. Even though the manual could be interpreted as allowing those rear gear oils. I don't think they will give a good shift feel in cold, and may be notchy when warmed up due to improper FM's and excessive EP's at the snychro interface.

I would explore the lower end of the 75W-90 viscosity spectrum in a GL-4 fluid. I recommend: Amsoil MTG GL-4 75W-90

 

[nyr197]

Redline MT-90 is a pretty good fluid.

 

[jbedford]

So how does the Redline MT-90 stack up to the Amsoil MTG GL-4 75W-90?

According to the stats online, it appears that the Redline outperforms the Amsoil product with higher flash point, lower pour point and a higher viscosity rating.

Redline - http://www.redlineoil.com/pdf/6.pdf

Amsoil - http://www.amsoil.com/storefront/mtg.aspx?zo=515729

Thoughts?


Jason

 

[Pablo]

Flash point really has no importance in gear box performance - of course assuming it's not ultra low like the spec. low limit of 150°

Pour points are within 1-2° C & F Not really much of a difference.

Kinematic viscosity of MT-90 is thicker at 40°C and 100°C. Not a huge difference. Maybe knowing what the viscosity of the current fluid is will help you decide which way you want to go here. What's in there now?

 

[jbedford]

Not sure - whatever the standard Mazda fluids are. They replaced the clutch under warranty about 30,000 km ago. I should have asked - but figured if it was being done with Mazda - that it would be alright.

Now that the car is off warranty - I want to safely experiment with fluids to improve the feel and performance of the transmission.

Jason

 

[jbedford]

Do I need to do anything special changing from the factory transmission oil to synthetic oil? Is there a flush product that is necessary, or do I just drive the car to warm it up, and let it drain for a long time?

Help?


Jason

 

[Pablo]

Just warm it up really good and let it drain a good while.

There are more anal ways to get all the fluid out such as blocking the car up and starting it and placing in gear, or you could more safely run a low cost fluid for a few hundred miles as a rinse.

Not really mandatory, but really anal.

 

[Big Jim]

Quote:

---

Just warm it up really good and let it drain a good while.

There are more anal ways to get all the fluid out such as blocking the car up and starting it and placing in gear, or you could more safely run a low cost fluid for a few hundred miles as a rinse.

Not really mandatory, but really anal.

---

And some might say really dumb.

 

[Pablo]

Quote:

---

Quote:

---

Just warm it up really good and let it drain a good while.

There are more anal ways to get all the fluid out such as blocking the car up and starting it and placing in gear, or you could more safely run a low cost fluid for a few hundred miles as a rinse.

Not really mandatory, but really anal.

---

And some might say really dumb.

---

No doubt - especially the guy with broken cinder blocks and car through back wall of garage headed for the neighbor's yard.....

 

[m2200b]

My first change to syn from dino trannie or diff fluids I usually change again at 30K rather than spend alot of time on the old dino ( draining or flushing). However I'm usually switching to syn with cars at 140k miles or more. I
d probably do a longer OCI on syn you put in or change when the shift quality goes down again.

 

[unDummy]

Its a coin toss between Redline MT90 and Amsoil MTG. Since identical transmissions can be fluid picky, you'll have to pick one and try it. If you don't like it, in ~50k km or earlier is you like wasting money on lubes, try the other one.

You should also change that gearoil every 50k-60k km or every couple of years. I'm a preventive maintenance junkie and its better to be safe then sorry if you plan on keeping the vehicle long past the warranty.

Don't assume gear oil is changed with a clutch job. You'd be surprised how many transmissions I've pulled for clutches that I didn't get new gear oil. Unless the TSB/recall specifically states a fluid change and its mentioned in your receipt, assume that it wasn't done. Topoff and go is common at dealerships. And even if it was changed by the dealer, unless they verify the PN of the fluid used, assumed they used generic bulk gear oil so common at dealerships.

No flush product is needed. Actually, unless there was some major water ingestion, IMO, I won't recommend anything in the manual transmission. For peace of mind, if you are happy with the new fluid picked, consider an earlier 'rinse' change
Since Mazda tends to allow both GL4 or GL5 90wt gear oils(check your owners manual or service manual), besides the GL4 gear oils, there are some good GL5 and dual rated ones that work well in manuals.

Redline MT90
RoyalPurple Maxgear
Redline 75w90NS
Amsoil MTG
Motul Gear 300
Neo 75w90HD
Lubro-Moly Vollsynthese
Castrol Syntrax

 

[jbedford]

Great information - thanks everyone - I think I'm going to give the Redline MT-90 fluid a go - since that is what most of the guys on the Mazda forums recommend.

RE: Gear oil - what would you recommend for the Mazda 5 speed MTX?



JB