Honda MTF, 8707 miles, 2004 S2000

[JSRT4]

Originally Posted By: INDYMAC
I think you'll be pleased with that OCI using GMSMFM. I found Honda MTF II to be better than GMSMFM, but GMSMFM to be better than MTF I. But I can't over-emphasize enough that picking a tranny fluid is very subjective in this car.


Well if you've tried both and found Honda MTF2 to be the best, I might as well stick with it. I have zero issues with my tranny, an 02 with 55k miles, I might as well stick with the Honda fluid. My interest was peaked by guys claiming that GMSMFM felt improved over the Honda fluid. If I stick to 5k oci's on Honda MTF2 it should be sufficient I think. I wish I could see some UOAs of both fluids though, I may have my Honda fluid UOA sample in the next month or so.

 

[turbosix]

i'm about to pull the trigger on some new trans / diff fluid myself.

last time i changed it was.. well... like previously posted:when the trans started to get notchy.

i decided to give RP a try, synchromax MTF and max-gear 75w90 in the rear and i really have no complaints... my rear is slightly noisy (as they all seem to be) and the trans shifted just nice and fine until the last month or so. its getting notchy again so its about time to put'er up on jack stands and get with it.

anyone have experience with amsoil stuff in the trans and rear? i was thinking about giving their 75w110 (maybe 75w140?) and their Synthetic Synchromesh Transmission Fluid (5W-30) a try.

 

[INDYMAC]

I think the 75W-110 SVT and 5W-30 MTF would be a good change for you. I have not tried either myself though. Since you live in Texas, I think LE 1605 SAE 110 would work well too. I do use that gear oil.

 

[dparm]

Wow. My 2005 S2000 (F22 with different gearing and lower redline) ran the OEM MTF for several autocrosses and track days, and it still shifted perfectly after 10k of "hard driving". I guess the earlier ones really were strung out.

 

[MolaKule]

Quote:
The Honda MTF is much thinner after only 8700 miles. May be Amsoil or Redline MTF are better than Honda MTF for 20-30k miles.


Well, it starts out at an ATF viscosity and sheared a bit.

It appears the AW additive is hanging in there, however.

How many wear metals you see depends on how you shift and how far down the line this fluid is from the OEM fluid.

Run at least two more analyses with the same fluid at the same intervals and see if the trends are better or worse.

You can't tell anything with a one UOA snapshot.

Mola

 

[INDYMAC]

Just to update what's going on now, I switched out the Schaeffers 10W-30 engine oil for AMSOIL MTF (5W-30) a couple of months ago. I decided to do this because the shifting was getting pretty stiff when the fluid was cold and took awhile to warm up. The cold oil temp shifting is stiff with the AMSOIL too, but not quite as much. The warm oil temp shifting is excellent though, but so was the 10W-30 engine oil. I'm going to do a couple of fills of AMSOIL and then test (UOA/VOA).

I think the Honda MTF II is an excellent choice for most, but I don't think it's up to the task in the Texas summer heat especially after it shears. Maybe a Honda MTF II winter fill, and an AMSOIL MTF summer fill is the ticket!

 

[INDYMAC]

One other thing I noticed that was happening on occasion with MTF II that I didn't like was it started popping out of 1st gear while trying to start going after a dead stop or while just pulling out of my garage in the morning. It wasn't that often, but it was happening. And it was only happening during the first 3-5 miles of driving (oil still cold).

It never happened again after switching to 10W-30 engine oil or 5W-30 AMSOIL MTF (8 months now). I can't even to begin to speculate intelligently why this was starting to happen, but I'm glad it hasn't happened in awhile!

 

[cheetahdriver]

I think we have spoken of it before, but the miata folks still seem to think that the Motorcraft Full Synthetic Manual Transmission Fluid is the best stuff for the Aisin transmission (the S2000 and NB Miata 6spd use the same transmission made by Aisin). I have a 02 using Molakule's SF-MTL-R(?) and a 04 MazdaSpeed Miata (turbo) using the Motorcraft. With about 80k on the SF fluid, the Motorcraft is just about the same (with 20k on it).

Two of the guys have tried the Honda MTFII (at my advice). They both thought it was great at first, and then dropped it after about 20k, and are both now running Motorcraft.

The Aisin transmission seems to be one of the most variable built transmissions I have ever seen. No two are exactly alike, and some will shrug off any lubricant fix.

 

[ltslimjim]

Originally Posted By: INDYMAC
Just to update what's going on now, I switched out the Schaeffers 10W-30 engine oil for AMSOIL MTF (5W-30) a couple of months ago. I decided to do this because the shifting was getting pretty stiff when the fluid was cold and took awhile to warm up. The cold oil temp shifting is stiff with the AMSOIL too, but not quite as much. The warm oil temp shifting is excellent though, but so was the 10W-30 engine oil. I'm going to do a couple of fills of AMSOIL and then test (UOA/VOA).

I think the Honda MTF II is an excellent choice for most, but I don't think it's up to the task in the Texas summer heat especially after it shears. Maybe a Honda MTF II winter fill, and an AMSOIL MTF summer fill is the ticket!


Look forward to that!

 

[Bror Jace]

Cheetahdriver, that's quite a leap up in viscosity. Honda MTF 1 was about 10.0 - 11.0 cSt (Amsoil Syncromesh is similar in weight) and Honda MTF II is ATF thin (7.5 cSt).

The Motorcraft fluid you spec'd is a real ninety weight gear oil coming in at 15.4 cSt. Even though I only drive my car in relatively warm weather (never below 50F), I'd be very reluctant to use such a thick fluid in a finicky trans.

 

[cheetahdriver]

The manual spec on the Miata Aisin is for a 75w90, what was the original spec on the S2000? My personal opinion is that with the GMSFM you trade some wear for performance that you are mostly getting from the Friction Modifiers, which the Motorcraft has as well.

In either event, I have been driving both Miata (Miatie?) this winter, and the Motorcraft stuff does as good as Molakule's Special Sauce in the cold. Which is a durn good trick, considering that the SF fluid is 80k old...

 

[INDYMAC]

The owner's manual doesn't list a grade of MTF/L for the S2000. It just says to use Honda MTF, or 10W-30 engine oil if MTF is unavailable. Maybe the maintenance manual is more specific as to SAE grade, but I don't have one.

I have actually seen reports of people trying M1 75W-90 or AMSOIL MTG 75W-90 with excellent (subjective) results. But my personal experience mixing AMSOIL MTF and MTG has steered me away from the 75W-90 idea.

So far, I'm enjoying the AMSOIL MTF. I'm looking forward to a summertime evaluation soon.

 

[cheetahdriver]

so Honda's MTL is about a 75w85, while the Motorcraft is a 75w90. i find it quite interesting (and somewhat confusing) that Honda and Mazda came up with 2 different specs for exactly the same transmission. OTOH, i know Honda took quite a bit of a pounding over the shifting in the S2000. Mazda did on their 6spd too, but the miata is a cheaper car, and many were sold with the 5spd, so it wasn't as bad.

that durn Aisin was enough to make me seriously consider selling my 02 until i put the SF MTL in it (thanks Molakule). the 5spd in the miata is so good that you need a cigarette after a good run in the twistys, with pretty much any lube that you care to put in it. the 6spd without the right stuff feels more like you are trying to open a door while holding a stack of boxes....

 

[ltslimjim]

I definitely will be giving Amsoil MTF(Synchromesh 5w-30) a shot during my next fluid change.

Question, though this is my first time replacing MTF myself...do I need to use the replacement crush washers from Honda or would any equivalent at an autoparts store do? I don't have a torque wrench(though may invest in one for cheap just for jobs like this), and would like to be able to just get it real tight so I know with the washer in place it won't leak/back out.

 

[INDYMAC]

This DIY link will help you through your first time:

http://www.s2ki.com/s2000/topic/565855-transmission-fluid-change-diy/

 

[cheetahdriver]

Originally Posted By: INDYMAC
This DIY link will help you through your first time:

http://www.s2ki.com/s2000/topic/565855-transmission-fluid-change-diy/


you have GOT to love cars that have highly active online support groups....

 

[ltslimjim]

So, any updates on your S2000 IM?

I've got Amsoil's Synchromesh MTF in my old Civic right now, good feel and I'm pleased. Thinking of getting a UOA afterward, hoping it lasts at least 24,000(about 2 years at the mileage per year rate currently), feel wise.

My primary concerns otherwise are wear numbers and viscosity staying within a 30 multi-grade range.

 

[INDYMAC]

I think the Ams MTF is a good compromise for the S2000. I have about 3K miles on this fill, and my transmission is telling me it's about time for a change. 2nd gear shifts tend to balk on occasion, and some of the other gears are beginning to get a bit notchy. It's been awfully warm here in Texas this summer! After this next fill of Ams MTF I'll send in a sample for testing. I think I'll bleed the clutch and brakes, and change the diff fluid while I have it on jack stands.

 

[ltslimjim]

^Awesome, thanks for the update.

I read back on another thread here regarding the thickness of the older Honda Genuine MTF that was around back in the 90s, like used in my car. Would you say the Amsoil is of similar viscosity? In other words, I was under the impression that the older HG product was perhaps around a 10w-30 while the newer HG is closer to a 20 multi-grade.

...and do dealers even carry the older spec'd MTF? I know they don't carry the older coolant for my app, but I'm thinking of just using the new HG Type-II coolant anyway unless someone else has reason to object to that as well.

 

[INDYMAC]

I think the original Honda MTF might have been a 30 grade, but I only say that because my owner's manual says to use it or 10W-30 engine oil. The MTF II appears to be in the 20 grade range based on VOA and UOA. You might find a dealer that has the older stuff laying around somewhere.

I did drain and fill the tranny yesterday with Ams MTF. The shifting feels much better again. I noticed that there was no reference to viscosity grade on the bottles I have. I thought it used to say 5W-30 on the front label. I also noticed that it doesn't refer to being a direct replacement for Honda MTF anymore. So maybe we can assume it's still a 30 grade? Also, I wonder why Amsoil uses engine oil viscosity grades to identify a gear oil.