How to change manual transmission fluid

Where DIYs with photos live. Please start new topics in DIY section. Completed DIYs are moved here for clutter control and quicker reference.
Post Reply
User avatar
redmed
Posts: 492
Joined: Fri Oct 01, 2010 12:56 pm
Location: Michigan

Decisions, Decisions :roll:
64 Galaxie 68 Olds 442 65 Impala 70 VW Bug
74 Nissan B210 66 Chevelle 73 Olds 98 71 C20
75 Monza 82 Escort 75 E150 75 Civic 76 Accord
86 Escort 87 Taurus 83 Chevy G20 85 Ranger 4x4
93 F250 4x4 95 Silhouette 95 LHS 03 Corolla 10 Kizashi S MT
17 Sienna
User avatar
KuroNekko
Posts: 5170
Joined: Wed Aug 15, 2012 5:08 pm
Location: California, USA

I don't know about you guys, but I thought the Kizashi's shifter with the factory fill was rather disappointing. Other than the medium throw and somewhat imprecise shift path, I thought the gear shifts felt "watery". Changing the fluid to MT-90 made shifting significantly better and feel more buffered. Maybe it's a personal preference, but I liked the difference MT-90 made. Also, MT-90 didn't make shifting in cold weather all that much worse than the factory fill. Last winter, I was driving around in 7 F (-14 C) temperatures and my shifter did not disappoint. Maybe a different story in -30 C weather like in the Mid West and Canada, but most owners don't experience those kinds of temperatures.

Another thing is that I hear quite a bit of gear rattle when in 2nd gear and under speeds of 20 MPH. I hear it occasionally in stop and go traffic and commonly when coasting in 2nd down residential streets. I've heard it with the factory fill and even so with MT-90. Anyone else's Kizashi make this noise? I assume it's rather normal because my Mazda3 did something similar.

Lastly, I want to note that MT-90 made absolutely no measurable impact on fuel economy. I changed the fluid almost exactly 1 year after buying the car. Until that time, it had the factory fill. It's now 1 year since I changed to MT-90. My fuel economy averages have not changed by any noticeable amount.

What weight is best for you mostly depends on where you live and what you want your shifter to feel like. I'm not a fan of watery and light-feeling shifters. As I've said before, the Kizashi's shifter is a downgrade compared to the one in my Mazda3 which was notchier, heavier, and far more precise. Switching to MT-90 in the Kizashi helped the shifter feel better for me.

If you live in a place that gets very cold, maybe 75W-80 is better, but theoretically, it should not make much of a difference due to the fact that they are all rated 75W meaning they all have flow characteristics of 75 weight in W (Winter) meaning cold temps.

All this being said, I may try MTL next to see how I like it and how the car likes it. I just simply think using MT-90 in a car "recommended" to use 75W-80 isn't a big deal especially since Suzuki says the weight is acceptable.
It may be that the only benefit MT-90 brought was the more buffered, smoother shifting feel, but that's exactly what I was going for.
2011 Suzuki Kizashi Sport GTS 6MT (Black)
bootymac
Posts: 1602
Joined: Fri Jul 19, 2013 1:04 am

KuroNekko wrote:If you live in a place that gets very cold, maybe 75W-80 is better, but theoretically, it should not make much of a difference due to the fact that they are all rated 75W meaning they all have flow characteristics of 75 weight in W (Winter) meaning cold temps.
Not completely accurate (on paper at least). According to Redline, MT90 is similar to 15w-40 engine oil, while MT85 and MTL are 5w-30. Gear and engine oil have different viscosity gradings for whatever reason.

Here's the rest of the tech info if anyone is interested:

MT90:
Gear oil: 75w90
Pour point: -45C
Viscosity @ 100C: 15.6
Viscosity @ 40C: 90
Engine oil: 15w40

MT85:
Gear oil: 75w85
Pour point: -48C
Viscosity @ 100C: 12.0
Viscosity @ 40C: 64.3
Engine oil: 5w30

MTL:
Gear oil: 75w80
Pour point: -50C
Viscosity @ 100C: 10.4
Viscosity @ 40C: 54.1
Engine oil: 5w30

Theorycrafting aside, MT85 or MTL might help with shifting into first and second in cold starts. Let us know what your experiences are with it!
User avatar
KuroNekko
Posts: 5170
Joined: Wed Aug 15, 2012 5:08 pm
Location: California, USA

bootymac wrote: Not completely accurate (on paper at least). According to Redline, MT90 is similar to 15w-40 engine oil, while MT85 and MTL are 5w-30. Gear and engine oil have different viscosity gradings for whatever reason.

Here's the rest of the tech info if anyone is interested:

MT90:
Gear oil: 75w90
Pour point: -45C
Viscosity @ 100C: 15.6
Viscosity @ 40C: 90
Engine oil: 15w40

MT85:
Gear oil: 75w85
Pour point: -48C
Viscosity @ 100C: 12.0
Viscosity @ 40C: 64.3
Engine oil: 5w30

MTL:
Gear oil: 75w80
Pour point: -50C
Viscosity @ 100C: 10.4
Viscosity @ 40C: 54.1
Engine oil: 5w30

Theorycrafting aside, MT85 or MTL might help with shifting into first and second in cold starts. Let us know what your experiences are with it!
They have this written on the page for MT-90:
"75W90 GL-4 gear oil (similar to SAE 5W40/10W40 engine oil viscosity)". Maybe it's a typo as it states 15W-40 elsewhere.

http://www.redlineoil.com/product.aspx?pid=46&pcid=7

Regardless, it's from my experience in actually using it that it doesn't make shifting much worse in the cold while it made normal (warm) shifting considerably better. If you live anywhere where it doesn't even snow much (Australia, the South, the South West, etc.) the cold viscosity is really not much of a concern. You'd have to see negative C or single digit F temperatures for the viscosity difference to really start affecting shifting performance.
2011 Suzuki Kizashi Sport GTS 6MT (Black)
User avatar
redmed
Posts: 492
Joined: Fri Oct 01, 2010 12:56 pm
Location: Michigan

bootymac wrote:
redmed wrote:
bootymac wrote:Redline makes MTL in 75w80 and it's also GL4. Sounds like a winner (if you can find it)

http://www.redlineoil.com/product.aspx?pid=45&pcid=7
MTL is also under consideration. The main consideration is what can I get locally.
You live in the United States of Amazon:

MTL:
MT85:
MT90:
I get stuff from Amazon all the time. In Fact, the FedEx guy just handed me a box from Amazon today as I was cutting the grass. But for gear oil I want to know I can get it locally and not have overnight it.
64 Galaxie 68 Olds 442 65 Impala 70 VW Bug
74 Nissan B210 66 Chevelle 73 Olds 98 71 C20
75 Monza 82 Escort 75 E150 75 Civic 76 Accord
86 Escort 87 Taurus 83 Chevy G20 85 Ranger 4x4
93 F250 4x4 95 Silhouette 95 LHS 03 Corolla 10 Kizashi S MT
17 Sienna
User avatar
redmed
Posts: 492
Joined: Fri Oct 01, 2010 12:56 pm
Location: Michigan

KuroNekko wrote:I don't know about you guys, but I thought the Kizashi's shifter with the factory fill was rather disappointing. Other than the medium throw and somewhat imprecise shift path, I thought the gear shifts felt "watery". Changing the fluid to MT-90 made shifting significantly better and feel more buffered. Maybe it's a personal preference, but I liked the difference MT-90 made. Also, MT-90 didn't make shifting in cold weather all that much worse than the factory fill. Last winter, I was driving around in 7 F (-14 C) temperatures and my shifter did not disappoint. Maybe a different story in -30 C weather like in the Mid West and Canada, but most owners don't experience those kinds of temperatures.

Another thing is that I hear quite a bit of gear rattle when in 2nd gear and under speeds of 20 MPH. I hear it occasionally in stop and go traffic and commonly when coasting in 2nd down residential streets. I've heard it with the factory fill and even so with MT-90. Anyone else's Kizashi make this noise? I assume it's rather normal because my Mazda3 did something similar.

Lastly, I want to note that MT-90 made absolutely no measurable impact on fuel economy. I changed the fluid almost exactly 1 year after buying the car. Until that time, it had the factory fill. It's now 1 year since I changed to MT-90. My fuel economy averages have not changed by any noticeable amount.

What weight is best for you mostly depends on where you live and what you want your shifter to feel like. I'm not a fan of watery and light-feeling shifters. As I've said before, the Kizashi's shifter is a downgrade compared to the one in my Mazda3 which was notchier, heavier, and far more precise. Switching to MT-90 in the Kizashi helped the shifter feel better for me.

If you live in a place that gets very cold, maybe 75W-80 is better, but theoretically, it should not make much of a difference due to the fact that they are all rated 75W meaning they all have flow characteristics of 75 weight in W (Winter) meaning cold temps.

All this being said, I may try MTL next to see how I like it and how the car likes it. I just simply think using MT-90 in a car "recommended" to use 75W-80 isn't a big deal especially since Suzuki says the weight is acceptable.
It may be that the only benefit MT-90 brought was the more buffered, smoother shifting feel, but that's exactly what I was going for.
The Kizashi shift is not much different than other cable linkage shifters I've used. A little vague going into third gear at times, but not bothersome. I have not any gear rattle in second gear. Only the reverse gear engagement problem.

The main reason I'm changing the transmission oil is that in my Ford Ranger I fried my gears due to no gear oil at about 73-75k miles. Before that I did not worry much about transmission oil. I never noticed any leakage from the trans so I was surprised when the trans locked up on me. Because the Ranger was a 4x4 with a 4 cyl engine (a rare combination) I had to order the gears from the dealer, an expensive lesson, rather than grab a trans from the junk yard. I have one of the gears in my workshop as a reminder. I want to do a complete refill with a good synthetic oil so I don't have that experience again with the Kizashi. I doubt finding a manual transmission for a Kizashi in a junk yard would be easy.

As a side note that manual transmission in that Ford Ranger was made by Mazda. While I have a high opinion of Japanese designed products my opinion of Mazda has been tarnished because of that transmission.
64 Galaxie 68 Olds 442 65 Impala 70 VW Bug
74 Nissan B210 66 Chevelle 73 Olds 98 71 C20
75 Monza 82 Escort 75 E150 75 Civic 76 Accord
86 Escort 87 Taurus 83 Chevy G20 85 Ranger 4x4
93 F250 4x4 95 Silhouette 95 LHS 03 Corolla 10 Kizashi S MT
17 Sienna
bootymac
Posts: 1602
Joined: Fri Jul 19, 2013 1:04 am

KuroNekko wrote:Regardless, it's from my experience in actually using it that it doesn't make shifting much worse in the cold while it made normal (warm) shifting considerably better.
So that confirms that MT90 is an improvement over the stock fluid. I wonder what the thinner MTL will do... When are you due for a change?
User avatar
KuroNekko
Posts: 5170
Joined: Wed Aug 15, 2012 5:08 pm
Location: California, USA

redmed wrote: As a side note that manual transmission in that Ford Ranger was made by Mazda. While I have a high opinion of Japanese designed products my opinion of Mazda has been tarnished because of that transmission.
Personally, I'd change the MT fluid at least every 40,000 miles regardless of what the owner's manual says. My Mazda3's MT was excellent and significantly better than the Kizashi's in my opinion. I changed the fluid around 60K, shortly after I bought the used car and replaced whatever it had (probably original fill) to Royal Purple Max Gear. It remedied a strange vibration feeling from the clutch pedal immediately. After about 35K on that, I swapped it out for Redline MT-90. The transmission never gave me issues with either of the quality synthetic fluids.

Mazdas aren't as durable as the other Japanese brands in my opinion but their cars are always better to drive, regardless of what is it. Everything from their subcompact (Mazda2) to their 3-row SUV (Mazda CX-9) are said to be better handling vehicles than most, if not all, of their rivals. They value driving dynamics which is rather nice for the segments they build cars for. Most rivals see it as an afterthought.
bootymac wrote: So that confirms that MT90 is an improvement over the stock fluid. I wonder what the thinner MTL will do... When are you due for a change?
Not for about 25K miles, even on my truncated service schedule. :lol:
2011 Suzuki Kizashi Sport GTS 6MT (Black)
User avatar
redmed
Posts: 492
Joined: Fri Oct 01, 2010 12:56 pm
Location: Michigan

I took a Altima for a test drive just before I bought my Kizashi. I had heard many raves about Mazda's & Altima's, so I wanted to keep an open mind and give an Altima a chance. The salesman came on the drive and talked & talked, so I could not concentrate. Plus most of the drive ended up being straight flat Expressway, in a automatic Altima. They would have to special order a Altima with a manual transmission and pushed me real hard to get a automatic, which they had "Great Deals On". I just wanted to get away from that salesman. So my Altima test drive was not really fair. From what I can remember the driving dynamic, which is the main thing I was trying to experience, did not impress. But, again what can what someone experience on a straight road with constant chatter in your ear.
64 Galaxie 68 Olds 442 65 Impala 70 VW Bug
74 Nissan B210 66 Chevelle 73 Olds 98 71 C20
75 Monza 82 Escort 75 E150 75 Civic 76 Accord
86 Escort 87 Taurus 83 Chevy G20 85 Ranger 4x4
93 F250 4x4 95 Silhouette 95 LHS 03 Corolla 10 Kizashi S MT
17 Sienna
bootymac
Posts: 1602
Joined: Fri Jul 19, 2013 1:04 am

Found some interesting info here: http://www.smokinvette.com/corvette/art ... es-part-2/

Edit: Test was performed by Amsoil. The final scoring is just a ranking and they also include price as a metric. Read the test itself for details of each oil's performance

Image

Image

Image
Post Reply