What Manual Trans Fluid Do You Use?

[KevBRZ]

i have about 1000 miles on my manual transmission new fluid. The tranny was getting really notchy, i bought the car with 40k miles on it and i am thinking it was never changed, i tried Redline MTF and so far it is tons better and almost completely eliminated all notchiness except a cold start ups for the first few minutes, i really haven't encountered any really cold temps < 30 degrees F yet so i am wondering how its gonna be this coming winter. but so far i am happy with it

[Yellow BReeZe]

Just bought my used 2017 BRZ with 8,000miles in November. I absolutely love this car, even though it has less power than my '02 WRX. Been having the same issue with second gear crunch as the weather got colder. The BRZ does great after it has been driven for about 10 minutes and the oil in the transmission has warmed up.


So after reading many posts, from all the sites, about the BRZ/FRS/86 6 speed manual transmission, I came to these conclusions:


1 - It was recommended to stick with OEM Subaru transmission fluid.
2 - It needs to be a GL-4 rated oil (due to the bronze & copper rings in the transmission)
3 - Change all the fluids as soon as you get the car. Transmission oil drain magnets seem to always be gunked up with a ton of metal shavings from the original oil.



I made my appointment with Subaru for this past Monday, to change engine, transmission and rear axle fluids. They neglected the transmission and rear axle because it wasn't necessary yet (22,000 recommended) so I had to bring the car back the next day to get them done.


Got in the car, sat at the dealership for about 5 minutes and then started to drive. Pulling out of their parking lot into traffic, I could not even shift into 2nd gear. Felt like someone put a block in to prevent it shifting. As the transmission warmed up from driving, shifting did get better.


I was expecting that the oil change was going to drastically improve the shifting, but it is now far worse than it was. On these cold Mid-Atlantic days, it takes 5 to 10 minutes of driving to get the transmission oil warmed up to where the car has fewer issues with 2nd gear. But I have also noticed that while the transmission oil is cold, I have a slight catch when shifting out of 1st gear, besides not being able to shift into 2nd gear. Been doing more 1st to 3rd shifts till the car warms.



I looked at the Subaru invoice and it turns out they used OEM GL5 80W90 for both the transmission and the rear axle. Great, they did not listen to my request for using a GL-4 in the transmission.


So, sometime this week, depending on the temps here, I am going to get my BRZ jacked up, drain the GL-5 oil currently in the transmission and put in:
Red Line MT-90 GL-4 Full Synthetic High-Performance Lubricant for
Manual Transmissions and Transaxles


This was recommended in several of the posts as working on the 2nd gear issue.


I'll see how that goes and report back with my observations. Maybe a plug-in heater for the transmission is needed for winter driving.

[Yellow BReeZe]

The weather cooperated this afternoon, I got the BRZ up on stands and proceeded with the operation.


As I noted in the previous post, I had the Subaru dealer replace all the oils in the car last Monday/Tuesday. Stole a couple of the oversized pee pads the wife used to use in the cat's litter box, spread them under the car, got my oil catch can out and took out the top fill plug on the transmission.


**Possible problem: When I removed the fill plug, oil immediately began to flow out! I thought I had spaced out and removed the bottom drain plug by accident, but I hadn't. Don't know how the dealership did it, but there was an excess of transmission oil in the transmission. Below is a picture of the car on stands to show that I was level when doing this.


Not sure if this added to the dilemma of 2nd gear shift or not but there should not have been this much extra fluid in the transmission. Judging by how much was in the catch can, I would guesstimate approximately 12 to 16 ounces of additional fluid.


From there, I removed the drain plug, drained the oil, replaced the drain plug and added the Red Line MT-90. Hope Fumoto comes out with a valve drain plug for the Transmission by the time I do the next change. Filled the transmission till fluid started to drip out of the fill hole. Once the drips mostly subsided, I put the fill plug back in, torqued it to 27.3 ft lbs, cleared the area and dropped the BRZ off the stands.


Hopped in the car and took it for a drive. Outside temp was 51°F but the car was not very warm as the blue engine cold light in the dash was on. I took it slow for a while and shifting was really smooth in all gears. So much better than over the last week!


The real test will be the next few days with colder temps expected. Will post my results after the next few days.

[86MLR]

Originally Posted by Yellow BReeZe

The weather cooperated this afternoon, I got the BRZ up on stands and proceeded with the operation.


As I noted in the previous post, I had the Subaru dealer replace all the oils in the car last Monday/Tuesday. Stole a couple of the oversized pee pads the wife used to use in the cat's litter box, spread them under the car, got my oil catch can out and took out the top fill plug on the transmission.


**Possible problem: When I removed the fill plug, oil immediately began to flow out! I thought I had spaced out and removed the bottom drain plug by accident, but I hadn't. Don't know how the dealership did it, but there was an excess of transmission oil in the transmission. Below is a picture of the car on stands to show that I was level when doing this.


Not sure if this added to the dilemma of 2nd gear shift or not but there should not have been this much extra fluid in the transmission. Judging by how much was in the catch can, I would guesstimate approximately 12 to 16 ounces of additional fluid.


From there, I removed the drain plug, drained the oil, replaced the drain plug and added the Red Line MT-90. Hope Fumoto comes out with a valve drain plug for the Transmission by the time I do the next change. Filled the transmission till fluid started to drip out of the fill hole. Once the drips mostly subsided, I put the fill plug back in, torqued it to 27.3 ft lbs, cleared the area and dropped the BRZ off the stands.


Hopped in the car and took it for a drive. Outside temp was 51°F but the car was not very warm as the blue engine cold light in the dash was on. I took it slow for a while and shifting was really smooth in all gears. So much better than over the last week!


The real test will be the next few days with colder temps expected. Will post my results after the next few days.

Colour look nice.

Post an outside pic in the sun if you can.

I'm sick of all the white, grey, silver, red and blue cars.

It's nice to see something different for a change.

[86MLR]

Opps, forgot topic

Recommend by "my guy" who is way smarter than me.

"Apparently" this brand with it's additives and stuff is GTG in relation to all the metal bits and is as smooth as silk, when warm.

Makes servicing the drive line simple with only 1 product to buy.

Opinions may vary.

[Yellow BReeZe]

When it comes down to it, we all will have different opinions as to which oils to use in our cars.


I've been going over posts and articles about transmission fluids for the past few weeks and am trying to get to a fact based solution to our 2nd-gear-crunch in cold weather issue. As of yet, and I am surprised that there hasn't been something done gear wise, there hasn't been a mechanical "FIX" to the 2nd gear crunch, like in the 2002-03 WRX "glass transmission." And not having the mechanical expertise to follow a gear swap myself, fluids are the priority, especially since the problem diminishes once the fluids heat up in the transmission.


Starting with some factual information:


The findings in the Rymax Lubricants website, which are reflected in many of the articles pertaining to GL-4 and GL-5:


There are four different classifications for transmission/gear oil. These different classifications define a certain level of performance in driven axles and manual gearboxes. They are mainly important for the transport sector in North America, Africa and Asia. The active classifications are:


• GL-1
• GL-4
• GL-5
• MT-1

The higher the Extreme Pressure (EP), the higher the GL category is. It is important to know that the SAE Motor Oil Viscosity Chart (J300) is different from the SAE Gear Oil Chart (J306). The viscosity has no relation with the API Gear Oil Classification and should be chosen based on the recommendations from the manufacturer based on the temperatures where you will drive.

The main difference between GL-4 and GL-5 gear oils is the amount of EP additives. Sulphur/Phosphorus containing products are used as EP-additive. This additive has the purpose to prevent the occurrence of micro-welds on the gear flanks at the local high temperatures which prevail in EP circumstances (temperatures well in excess of 800℃!) GL-5 has roughly twice the amount of EP additives compared to GL-4, which is why it is often used in high-pressure circumstances such as in a front axle and rear axle differential.
Sulphur/Phosphorus additives however have an unfavourable property: they can react aggressively towards bronze and copper. This can be disastrous for the synchromesh rings of a gearbox. Therefore it is not recommended to use GL-5 in a gearbox unless the manufacturer allows this.

To conclude:
• GL-4 is suitable for hypoid gear service when they are under severe service but are without shock loading.
• GL-5 is suitable for hypoid gear service under severe service and shock loads and not for use in a gearbox.

The Subaru BRZ transmission contains both copper and bronze synchronizer rings. So it is completely up to you to use a gear oil (GL-5 rated) that can damage these rings over time (leading to costly repairs). Which could also be part of the reason we have this issue to begin with (My local Subaru dealership put GL-5 in my transmission last week and made my issues worse).


If you are using a GL-5 product in your transmission and are having great results in eliminating the 2nd gear "crunch" in colder weather (seems anything sub 50°F), Awesome! Please let us know and do not spare the details.


But the fact that all your lubricant manufacturers warn that GL-5 oils should not be used in transmissions like ours, should weigh on your decision on what should be put in your transmission.


Sadly, doing a search of the 2nd gear "crunch" shows that this problem has been around since the 1st gen BRZ/FRS. So this tells me that there isn't a real solution to the 2nd gear "crunch" and we are just looking for a fluid solution that most alleviates this issue.


Again, I am no mechanic, so I don't know if there is a mechanical solution worth pursuing, like the gear swap on the 2002-03 WRX 5 speed manual "glass" transmission. The only reason I know about this, I had 2 '02 WRXs and was close to taking the 2nd one up to a place in Northern Virginia that would swap out the "bad gears with some German gears.


I guess when I get up tomorrow and find out if the recent transmission oil change has helped or not, will lead to me searching out the gear swap route. Or perhaps wait and see what's coming in a 2021 BRZ.


Thank you to everyone who has added pertinent info to this topic!

[Yellow BReeZe]

Originally Posted by 86MLR

Colour look nice.

Post an outside pic in the sun if you can.

I'm sick of all the white, grey, silver, red and blue cars.

It's nice to see something different for a change.

Thank you! Happy to add more pics to my album shortly, instead of in this post. Thoroughly love my BRZ and definitely love the non-standard colors!
Series.Yellow was a limited run of 500 here in The States. There are a lot for sale at some really good prices.

[Muskoka800]

I bought my 2016 FRS with 27,000 kl on the clock from a dealer off lease.
I assume it had the original fluids still in use.
I had no nasty shift issues although it isn't winter driven.
I planned to do lapping so changed the fluid to Motul 300.
Immediately I experienced the crunch when cold (spring start-up cold, not winter cold) going from 1st to 2nd. Once driven a few blocks the crunch was gone. No issues downshifting at any time or temp.
I will likely change out the fluids with Motul 300 again this summer unless something better comes to light.

[Yellow BReeZe]

Ok. I've had 2 days with Sub 40° F mornings to see how the Red Line MT-90 GL-4 Transmission oil would work in colder temps and the 2nd gear "crunch."

Each time, I started the car and let it sit for 5 minutes, letting the engine warm up (which, in case you do not realize, does not warm up the transmission oil) before starting to drive. Pulled down our road in 1st for about 100 yards before turning onto the major street. Pulled out and took 1st gear to 3K rpms and shifted to 2nd. I was immediately thrilled that I was not locked out of 2nd gear, like I had been with the Subaru GL-5 80W90.

There was a slight catch going in to 2nd, but not like it had previously been. On the first ride, I continued on and and as the transmission oil warmed, all shifts between gears leveled out and were nice and smooth. On the second ride, when I would shift from 1st to 2nd, I tried something different.

Clutch in, pull out of 1st and let the shifter go to neutral (if you let go of the shifter and let it sit in Neutral on it's own, it sits in the spot between 3rd and 4th gears), then pulled it back over and down into 2nd. This is all a fairly quick motion and it seems to eliminate the little "catch' I felt on the first day of cold driving. I had tried double clutching when I had the Subaru GL-5 in, and it helped, but still had the "crunch" and the lock out a couple times.

Seeing as numerous people have had similar results as mine by changing the transmission oil with pretty much every brand out there, but not totally eliminating the 2nd gear "crunch," my recommendations would be as follows.

If you have the 2nd gear "crunch":
• Change out your transmission oil (Highly recommend a GL-4 oil).
• Take it easy when you start driving and let the transmission oil warm up.
• When cold, Double Clutch going from 1st to 2nd (or try my suggestion for drifting into Neutral).


For those living in colder climates, it might be worth trying an oil pan heating element:
https://www.amazon.com/Kats-24150-Wa...2394558&sr=8-8

Be nice to get some input from anyone who is using one or willing to try one out. For $35, I may just get one to see if it makes any difference on the car. I'll report back if I go that route, but as we have relatively mild winters in the Mid-Atlantic of the USA, that money may go towards something more necessary - like a ceramic coating.

Once my BRZ was warmed up, I haven't had any issues with the transmission gears.

Hope this helps shed a little light on this and I do hope that you all enjoy your BRZs as much as I am!!

[Yellow BReeZe]

A much colder 19° F to start this morning out. Did my 5 min engine warm up before driving off. Once I got over to the main road, did my little trick of shifting from 1st to Neutral and went smoothly into 2nd. Did that a couple more times before the transmission oil fully warmed up, but from then on it was smooth shifting.


Hope this helps so no one else has to really struggle thru this.

[Goingnowherefast]

Just another data point:

I use Ford's newish Motorcraft XT-M5-QS GL-5 MTF. I basically use this on all my manual cars that call for GL-5 and it's excellent. I prefer it to the Redline products, because it works very well at low temperatures too. It definitely had a great impact on overall shift quality, but it is fairly expensive.

[MotoX16]

Another here running MT-90. No issues I'm liking it much more than the stock fluid

[Yellow BReeZe]

Very happy with the results of the MT-90 especially with the colder temps here in Virginia, though probably not as cold as Minnesota or Michigan.


Thank you @Goingnowherefast for the heads up about Ford's Motorcraft XT-M5-QS GL-5 MTF!!


2017 Subaru BRZ Owner's Manual pages 475-76 refer to the oils usable in the rear axle and the Manual Transmission. (See pics below).


Since Subaru has okay'd the use of GL-5 in the transmission, there shouldn't be an issue, though countless manufacturers of GL-5 oils do not recommend it for our transmission (due to the copper and bronze rings).


For now, I am happy with the results of the Red Line MT-90 (sounds like @MotoX16 is as well) and will see how long it stays reliable, but will probably switch over to the Motorcraft XT-M5-QS GL-5 MTF. After doing a quick Google search, it seems that this stuff is being recommended on a variety of car site forums.


Thank you guys for the input!

[86MLR]

I'm going to get an analysis done on my gearbox oil at Mainlube in Botany, Australia when I change it out.

I'll drop off the sample to them, it will take 30 minutes for the test and evaluation, from there we will make a call of what is required.

Mainlube can decant a mix on site for me.

Mainlube have a really good name with their oils, choosing oil weight and required additives here, their oil is quite expensive but they build oils for alot of raceteams, heavy plant and industry.

I only need to grab 2.5ltrs of the stuff so additional cost isn't a worry.

They build their oil packs based of the analysis, type of metals used and the use of the equipment.

I'll post up when it's done, give me a few weeks.

I think this is a different process to Blackstone, but if it's good enough for heavy industry and race teams, it's good enough for me.

https://www.google.com/url?sa=t&sour...WIKIXS_zCTWs6-