Redline MT-LV 70W/75W gear oil for 5 speed manual Mirage (OE is 75W80)

[Daox]

Just a quick update. I received the oil as a present for Christmas. We'll see when I get some time to put it in the trans.

[MetroMPG]

How do you find the shifting in your Mirage on the original oil?

I know some owners have reported it is 'notchy', but I'm not sure what that means.

Have you had it during any REALLY cold weather yet.?

[csnyder]

My Ranger 4.0 5 speed recommends Dexron 2 ATF.

I had the oil "upgraded" to synthetic Mercon V - the supposed replacement for Dexron 2 which is no longer manufactured.
Shifting became PAINFULL. I lived with it for several years then switched back to conventional "universal" ATF. Over a period of several weeks the shifting improved markedly. It's now a pleasure to drive again. Absolutely no difference in fuel economy.
This is the Mazda built M50D

[Daox]

Originally Posted by MetroMPG

How do you find the shifting in your Mirage on the original oil?

I know some owners have reported it is 'notchy', but I'm not sure what that means.

Have you had it during any REALLY cold weather yet.?

I would agree that the shifting on the Mirage is a bit notchy. It doesn't smoothly glide from one gear to the next. But, its not hard to shift from one gear to the next, it just kind of isn't smooth while doing so.

This winter it really hasn't gotten THAT cold. I don't think I've driven in any -0F weather yet. That being said, I've honestly not noticed when it has been cold shifting wise. Its never gotten that thick 'push it to get in gear' feel. The OE 75W-80 does seem to do a decent job. It'll be interesting to see what the new fluid feels like.

[Joeman77]

I used to have a Subaru Justy that called for 75W-90, it was thick as mud when it got cold! When it was below zero you almost had to slip the clutch until the tranny got warmed up, not the motor mind you but the transmission! I went with Amsoil 75W-90and never looked back. It's about the consistancy of 10W-30 Dino-oil, gained about 3MPG! Now I use it in everything with a manual trans Cars, trucks & motorcycles, for almost 30 years now & nothing has failed yet and shifts are smooth as butter hot or cold!

[Ecky]

Subscribed. I hadn't yet thought much about what fluid to put in my new 6MT.

[ctgottapee]

Some trans oil additives could potentially get you similar results, but it would be even more guesswork and potentially risky.

Many are pretty thin

[diesel_john]

I have used John Deere HyGard in my Volkswagen manual transmission it worked fine in the winter but I got a little nervous in the summer because it only has splash lubrication and put some 75w in it.

[Daox]

It was a blissful -8F (-22C) this morning when I left for work. Granted, I did have the block heater running for a good while to warm up the engine (it was 90F when I started it up), but I could finally feel the gear oil making it a bit more difficult to shift. Not a horrible amount like I've had in previous cars with 75W90 gear oil, but you could feel it. I am still running the OE 75W80 gear oil. I wanted to experience at least one really cold day with it before swapping out. It doesn't get too much colder than that here, so today was the day.

Now, all I need is a nice warmish day to drain and refill the trans with the new Redline 70W/75W.

[aerohead]

Originally Posted by Daox

I was poking around today looking at different gear oils. The 2014+ Mirage calls for a 75W80 gear oil. The 75W is the engine viscosity when cold, and the 80 is the viscosity when its hot. All oil is substantially thicker when cold, so getting a low first number is a good thing as it will always be thinner when hot. You just don't want it to get too thin, or you can accelerate wear in your transmission. Here is a chart to help illustrate things.





Therefore, I was looking to see if I could get a 70W80 or even 65W80. Alas, I can not find anything like that. However, what I did find was Redline MT-LV 70W/75W. You'll notice this doesn't follow the normal naming convention. So, I'm not exactly sure what to think about it. It is quite a bit thinner than Redline MTL 75W80 that many here have used.



Here are the viscosity specs of the two:

75W/80 (OE spec)
Vis @ 100°C, CSt 10.2
Vis @ 40°C, CSt 50

70W/75W
Vis @ 100°C, CSt 6.5
Vis @ 40°C, CSt 9.8


For reference, 40C is 104F. That already seems warm for a manual transmission, but I haven't measured my transmission's temperature. Anyway, at 104F, you can see the 70W/75W is 5 times thinner than the 75W80 oil. Thats a heck of a lot less churning going on. Less churning means more power and efficiency.

Anyways, I post this info because I am thinking about using it in the Mirage. I have contacted Blackstone Labs, a third party oil analysis company. I've asked them how they recommend I proceed with testing this oil with minimal risk to my transmission. I've used them many times in the past for engine oil analysis and they're very helpful.

I tried this in the CRX and could not discern any improvement to mpg.
Also,I put a number of baby jars filled with various viscosity standard and synthetics into the freezer,and next day,did a simultaneous side-by-side tip-test,flow comparison,and the standard Valvoline 10-40W flowed just as well as the most expensive full-synthetic.
You may have a better experience.