Amsoil 75w90 manual transmission fluid in Mazda 3

[Orangepeel]

Factory recommendation is 75w80 gl4 for a 14 Mazda 3. Can I use amsoil 75w90 manual transmission fluid which says it's a gl4 as well. I know it's a little thicker but will this lubricant work well in this application?

 

[Lubener]

No problem using the 75w-90.

 

[tvaughn]

Some cars spec GL4 75w80 for a reason (e.g. yellow metals), may be worth looking into. Even from Amsoil's site:

GL-4 gear oils are typically recommended for spur and helical gears found in manual transmissions and transaxles operating under moderate speeds and loads.

GL-5 gear oils are typically recommended for hypoid gears in automotive axles operating under high-speed, high-load conditions.

I noticed Motul and Redline both recommended their 75w80 for your car.

 

[ceecbtg]

You can use it, but it's not the recommened viscosity.

 

[SC Maintenance]

You should stick with GL4 whatever you do as mentioned due to the possibility of brass synchro's. Some lubes claim there good for both GL4 / GL5 but I would be suspect personally.

In a gear oil 90 weight is a lot thicker than an 80 weight. I don't think that would hurt anything but it might not shift as easily.

 

[SubieRubyRoo]

Factory recommendation is 75w80 gl4 for a 14 Mazda 3. Can I use amsoil 75w90 manual transmission fluid which says it's a gl4 as well. I know it's a little thicker but will this lubricant work well in this application?

You can, but depending on your winter climate it may be a little hard shifting the first few miles in really cold weather.

I had used a variety of 75w90s on my Subaru manual, some were worse than others in winter (-5*F or so). I never tried Amsoil at that time but can tell you the Motul Gear 300 is really stiff into first gear for about 3-4 miles. I’d ask @Pablo if there’s a better choice if you’re interested in Amsoil; otherwise you may find the 75w90 Cold Climate from HPL may fit your needs.

Check out my 75w90 thread for a comparison of 11 different gear oils.

 

[Pablo]

Factory recommendation is 75w80 gl4 for a 14 Mazda 3. Can I use amsoil 75w90 manual transmission fluid which says it's a gl4 as well. I know it's a little thicker but will this lubricant work well in this application?

50/50 mix of Amsoil MTG 750-90 and Amsoil MTF.

 

[pbm]

Ravenol makes a GL4 75W80 gear oil that I bought on Amazon a few years ago.

 

[Orangepeel]

50/50 mix of Amsoil MTG 750-90 and Amsoil MTF.

Would that be manual trans 75w90 gear oil and synchromesh manual transmission fluid?

 

[Pablo]

Would that be manual trans 75w90 gear oil and synchromesh manual transmission fluid?

Exactly

 

[Orangepeel]

Exactly

Ok good to know. Is running straight amsoil synchromesh to thin I suppose?

 

[Pablo]

Ok good to know. Is running straight amsoil synchromesh to thin I suppose?

It might work. Maybe a bit thin. 9.7 cSt or so at 100°C. I think you need closer to 11

 

[facility1]

i used Amsoil gear synchromesh (MTL) in all of my past manual transmissions with great results, highly recommend..

 

[Pablo]

i used Amsoil gear synchromesh (MTL) in all of my past manual transmissions with great results, highly recommend..

Product code MTF. Thanks

 

[badtlc]

Ok good to know. Is running straight amsoil synchromesh to thin I suppose?

I had a 2012 Mazda3 MTX. I used Redline MTL. You want to use a thinner fluid. Despite what the manual says, it did not come with 75W90 from the factory. It is a very thin factory fluid.