2nd gear synchro FIX- MT owners read this thread

[cantholdanymore]

Any user reports now that the weather is warmer in the northern hemisphere?

[Esoteric]

Ok... After six different oil changes, many track days and mods... For us, the winner is...

Redline MTL and a Cusco/or Perrin trans brace... YES REALLY!

Fluid:
If you read the past posts, you will see that we tried A LOT of different fluids. The gear box was really not to our liking

We found the good old standards, the "do it all" fluids you see on so many forums, work a charm in the FT86 gearbox :
Snycromesh works well as it does in the Honda boxes, but we wanted more resistance to heat and longer life. The flexibility of the Redline MTL won our heart once again. (We use this EXTENSIVELY in BMW street cars and race cars and its performance is irrevocably well documented).

We found that the Redline MT-85 worked well but the higher viscosity requires very slightly increased shift effort... Hmm. When the snycros go to engage one another, this slightly thicker layer of oil is more to push out of the way, increasing the effort required to make the syncros come up to matching speed (what allows a smooth, fast, quiet shift)....

Pentosin was working really great, and by far the best in the very cold days... but from time to time, it felt a little funny... and we would still get a little 'crunch'... I had witness this phenomenon before! Was it too slippery?
A few emails and the tech at Redline already had a response for this:

"Clashing of gears may occur at the end of a reasonably smooth shift if an instability exists in the coefficient of friction, causing what we know as "stick-slip" to occur. In this form of clashing, the ring slides on the mating synchro gear, but a sudden slippage causes a grinding of the gears. In order to prevent stick-slip from occurring and the gear clashing which results, the coefficient of friction should inflect downward as the relative speed drops to zero. We don't need any abundance of friction modifyers for MTL to work great, just as it has been in your other apps."


As for the trans brace:
Stabilizing the fore-and-aft motion of the trans made a surprisingly strong difference vs. a polyurethane shifter-carrier bushing alone. The Whiteline trans bushing only braces laterally.
Like in other RWD cars, stabilizing the trans mounts has had a great impact on shift quality.

• Cliff Notes: MTL allows good protection of all wear items, but has slightly more friction between the synchronizers (where you want it!) while lasting a long time, and resisting high heat and load. A trans mount that braces fore and aft can improve shift quality with little to no NVH problems.

[rice_classic]

Originally Posted by Esoteric

Ok... After six different oil changes, many track days and mods... For us, the winner is...

Redline MTL and a Cusco/or Perrin trans brace... YES REALLY!

I am absolutely stunned by this.

The Honda road racing community won't dare put a redline product in their transmissions because under the torment of racing conditions Redline makes a new transmission feel like a broken one for the exact reasons you pointed out in reference to Pentosin (it's too slippery for synchros). Same goes for the S2000 guys (Former S2k guy) which shares a similar transmission design. I'm absolutely stunned at this result but glad to hear it nonetheless.

[tech4pdx]

Fwiw.. I've been running the Pentosin / Perrin trans mount combo for 7000 miles now with no ill effects. The factory fill was horrid.. Especially when the ambient temp fell below 40 F. I tried Redline MT-90 which was slightly better than stock but not by much. I haven't researched how different MTL is to MT-90. MTL might be thinner.

[cantholdanymore]

Originally Posted by Esoteric

Ok... After six different oil changes, many track days and mods... For us, the winner is...

Redline MTL and a Cusco/or Perrin trans brace... YES REALLY![/LIST]

Esoteric
Are you referring to this:
http://www.perrinperformance.com/brz...mission-stiffy

or this?
http://www.perrinperformance.com/par...trol-arm-brace

[michaelahess]

So 1 year to the day from buying the car I put in the Pentosin.

I went for a bit of a drive before hand to warm up the tranny so it would drain well. During this drive I took notes about the feel of the shifts. It was about 90 degrees outside.

There has always been a double "clink" when shifting first, second, and third, then a bit of resistance for the others. Never any crunching except when cold or downshifting without rev matching on 1-3. The first clink has always been nearly as, uh, clinky, as the actual engagement.

With the new fluid, I warmed it up a bit then drove various conditions and noticed the following:

1-3 shifts had almost no first clink (felt more like a little bump stop with the syncros), just the second actual engagement.

Without rev matching downshifts there was still a bit of syncro clinking, but maybe half of what it was like before. The "bite" wasn't there, more of a soft tap was all I got.

4-6 were perfectly smooth, instant click with no resistance.

Not sure if OEM fluid would have the same effect being a new fill, but I can say I don't recall the shifts being this clean when I first bought the car, though a year has a way of altering perceptions I suppose.

The drain plug had a lot of fine metal shavings, I got all I could off but some remained, needed a bigger magnet! Guess it's doing it's job however.

Something I wonder though, the original fluid had a metallic sheen to it, almost a pearlescent glittery glow. If I swished it around in the pan, fluid shapes would appear, like a picture on a latte kind of thing for want of a better description. Would that be considered normal after only 4k miles and 1 year or does that sound like it might have been too dirty?

Gotta say, first time doing a tranny fluid change, easier than oil! Getting that protection plate off was a pain though.

[roddy]

Originally Posted by tech4pdx

Fwiw.. I've been running the Pentosin / Perrin trans mount combo for 7000 miles now with no ill effects. The factory fill was horrid.. Especially when the ambient temp fell below 40 F. I tried Redline MT-90 which was slightly better than stock but not by much. I haven't researched how different MTL is to MT-90. MTL might be thinner.

It is. MT-90 is 75W90 MTL is 70W80.

[abutterman]

I'm about to try some Redline MTL 70w80. I currently have Amsoil 75w90 and it's been somewhat ok lately now that it's been warmer outside but i still have a bit of a crunchy feeling when shifting and a little bit of a thump sometimes when going into first at a full stop. I've yet to see any bad reviews on the MTL fluid and it's GL-4 so it should work fine in the transmission. I'll be combining that with a new perrin rear shifter bushing. hoping for the best.

[Numb]

Coming up on 1000 miles on my car. I did a track day at 800 miles (I couldn't wait any longer) on stock tranmission fluid. Changed it the next day to Motul Gear 300. Not bad but shifting was a bit stiff and some resistance going into 2nd and 3rd.

After reading through all of this I put Redline MTL in yesterday. Noticably better shifting. Much smoother and much better 2nd and 3rd gear shifting. The synchros seem to work better with this fluid and the car feels like it has a bit more power.

[sid325]

Originally Posted by roddy

It is. MT-90 is 75W90 MTL is 70W80.

Pentosin is 75w-80. Would there really be much of a difference with MTL at 70w-80?

[roddy]

Originally Posted by sid325

Pentosin is 75w-80. Would there really be much of a difference with MTL at 70w-80?

I don't remember the exact numbers at 40 and 100 degrees, but I don't think there would be a huge difference.
I went from stock to MT-90, and found it considerably better until the outside temps started to get below about 50 degrees F. Below that shifting suffered a bit and it took a long time to warm up. The whole time, Gem was adamant that Pentosin would be the cure, but I couldn't justify $30/liter on the word of someone I don't know from a hole in the ground. I had a couple of quarts of thinner stuff on the shelf, so I tried a mix of MTL and Honda MTF (similar in weight to the MTL) to see how the transmission liked a thinner fluid first. It was a big improvement, but I was still getting a slight catch occasionally on the 2-3 shift. I bit the bullet and ordered the Pentosin, and I've never looked back.
I never did get around to trying a full fill with MTL, so I can't say for sure how it works. As far as I can remember Esoteric is the only one who has posted using it. Others have reported good luck with MT-85 (75W85 GL4).
My car is a year 'round daily driver that sees temperatures from -20 to +90, and some fast backroad blasts, but no track time yet...I can't see myself switching fluids any time soon.

[Esoteric]

MT-85 was in fact the very first thing we tried, and of the 6, for a dedicated track car that's still likely what I would use. It works great as well, but below 55* degrees ambient it was still notchy and I knew the trans must be able to shift better.

Thus far everything tried has been better than the poor factory-fill gear fluid.

Originally Posted by sid325

Pentosin is 75w-80. Would there really be much of a difference with MTL at 70w-80?

Its not that there is just a difference in viscosity, its that the friction profileof MTL has been engineered to enhance the friction between syncros despite being a slippery synthetic. The graph here is to illustrate that as the RPM speed of the snycro slows, the Redline allows more "grip" between them so it gets rid of that last little grind/crunch between gears.

Redline accomplishes the thinner viscosity, with proper friction as they mention, this is also good for the life of the snycros as well:

Originally Posted by rice_classic

I'm absolutely stunned at this result but glad to hear it nonetheless.

Be stunned and then relived my friend.
MTL is about as common, and abundant as any performance gear lube, so this makes sourcing it a snap, and the price is right! The S2k trans similarities are one of the reasons we tried this variety of fluid last.

It's true, the Honda boxes do not work well with Redline (not just the S2K, but also the D & B series transmissions! They grind into second and third typically).


----
As for the trans brace, we use this one: Cusco Trans Mount Brace
Its modular, installed easily, and has very little effect on NVH. It actually gives a good tactile sense of things though the knob without buzzing or being annoying in any way.

This is the Perrin Transmission Support Mount

[abutterman]

Originally Posted by Numb

Coming up on 1000 miles on my car. I did a track day at 800 miles (I couldn't wait any longer) on stock tranmission fluid. Changed it the next day to Motul Gear 300. Not bad but shifting was a bit stiff and some resistance going into 2nd and 3rd.

After reading through all of this I put Redline MTL in yesterday. Noticably better shifting. Much smoother and much better 2nd and 3rd gear shifting. The synchros seem to work better with this fluid and the car feels like it has a bit more power.

this is awesome to hear. i'm just waiting on my friend to have some free time so we can use his jack stands to flush mine and put my MTL in. It's been sitting in the box waiting patiently

[abutterman]

Just did a fluid change to Redline MTL 70w80 as well as the Perrin rear shifter bushing and a Kartboy pulley. Shifting is much smoother all around. Had a good 45 minute drive home after installing everything and most of the resistance is gone and it tends to go into gear much easier