S2KI Honda S2000 Forums - Gearbox oil recommendation?

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Quote:

Originally Posted by 231sea (Post 24599464)

Dumb question: Is it better to change the transmission and gear oil while the fluid is warm? Like shortly after a drive?

yes you get more fluid out when it is warm compared to it being cold, particularly the diff fluid which can be quite thick. The difference might be minimal but that is the theory,.

Quote:

Originally Posted by Slowcrash_101 (Post 24598253)

Whatever fluid you use, change it frequently. Once a year minimum.

That is kind of a broad statement considering some only drive a couple thousand miles a year. I replace mine every second year with around 10000Kms or 6000Miles.

According to the idiot Honda engineers (what would they know?), but replace yours every few months -- at least once a year. :)

Maintenance Schedule for Normal Conditions:

Quote:

Replace manual transmission fluid
Every 120,000miles (192,000 km) or every 6 years, whichever comes first.

-- Chuck

Quote:

Originally Posted by Chuck S (Post 24594094)

For grins I looked up the maintenance schedule for the gearbox. Had to use the 2005 owners manual 'cuz there's no schedule in my 2006 manual, it's all in the Maintenance Minder.

Replace manual transmission fluid. Every 120,000miles (192,000 km) or every 6 years, whichever comes first. Honda expects their MTF to last quite a while! Anyone run theirs that long? (Severe service would be half that.) I have no scientific data indicating my gearbox shifts better or even differently from whatever oil the prior owner had in it in 2014 to the Honda MTF I put in the next spring to the Royal Purple SyncroMax in there now. A lot of this stuff is perception -- we expect the gearbox to be smoother with an oil change. And since I just rolled the odometer over 60,000 I'm sure the oil change has met specs.

Just a line below it on the same page: Replace rear differential fluid. Every 30,000miles (48,000 km) or every 2 years, whichever comes first. The differential is the one to be concerned with as to wear. I'll be changing this next month along with the engine oil. Gearbox is a game time decision but since I'm under the car and oil is cheap... :)

-- Chuck

The last time I pulled out transmission fluid that old was my last 2005, which had ~123k miles when I got it. The transmission fluid looked like heavily used engine oil coming out; it didn't feel/smell like it, but the visual consistency was the same.

I've run both Honda and Amsoil MTF and I would say that Amsoil has a slight edge in feel over Honda, though I doubt most would feel a difference. As has been said, the newness of the oil makes a bigger difference in the feel of the shifting. Since I mostly drive autox and street, I normally change my transmission and differerntial oils once a year unless I am running multiple track events that year, in which case I change it after a couple of events.

If I recall correctly, Spoon recommends replacing the MTF with every engine oil change.. what do they know that Honda doesn't?

Quote:

Originally Posted by fatjoe10 (Post 24600991)

If I recall correctly, Spoon recommends replacing the MTF with every engine oil change.. what do they know that Honda doesn't?

Spoon is a racing company , changing fluid with every oil change sounds reasonable in a racing environment, not needed in daily driving. Tranny fluid shears (becomes less viscous) with each mile of driving due to the meshing action of gears, so in a racing environment changing it more frequently makes sense - high heat and shearing fluid makes fluid even thinner than you want to risk.

Quote:

Originally Posted by fatjoe10 (Post 24600991)

If I recall correctly, Spoon recommends replacing the MTF with every engine oil change.. what do they know that Honda doesn't?

Ichishima-san did say in a Best MOTORing video that trans fluid should be changed more often than most people do because the engine oil gets changed out frequently so that's covered but the trans sometimes gets neglected. He definitely knows what he's talking about. He also said in the same show that you should never use engine flush.

Then again everyone's mileage differs quite literally. I made sure to change all my car's fluids before the last track day I entered for peace of mind, added protection and performance. As zero said, in a strictly racing environment such as that of Spoon's S2000 builds it would be reasonable and desirable to change the trans fluid at every oil change which for them could be after every race (depending on conditions, length/laps, etc). I intend to change my trans and diff fluids at shorter intervals than recommended by Honda.

Okay so another update. I put Amsoil MTF in the trans. Wow huge difference! The second gear grind is all but gone and no need to drive around for 10 minutes to let it warm up. I can still feel some clunky shifts, mostly in 3rd.

It has a new clutch master cylinder because it was drippy, and the clutch grabs strong. I'm not sure what can still be causing the shifting to feel this way still. It just started last year with no warning: the 'almost grind.' Or an occasional actual grind on 2nd, which is gone now since Amsoil.

I think I read Billman talking about rusty spline can cause this? Maybe I need an expert opinion, I could visit Darcy maybe. Other ideas anyone?

^ I told you Amsoil was an improvement , it is especially good when cold too.

It can take a couple weeks to get the full benefit from a fluid change, as it mixes with the remnants of the old fluid and becomes more homogenous and the additives plate up.. I think you will find it shifts even better over the next 2 weeks of use.

I honestly feel with the S2000 the hand moves faster than the foot, with your hand being so close to the shifter, unlike other cars where you have to reach further to grab the shifter. Having the clutch at the fully disengaged point for a fraction of a second more, the smoother the shift will be. That's why tightening up the clutch rod freeplay works so well, the tighter the clearance the better.

Yes you were totally right! My concern is that it happened and I didn't change my driving style but ever since I've been extra careful... Which really takes the wind out of your sails when just booting around. I've changed the MC and adjusted for minimal Freeplay, and changed the trans fluid, which have helped but not eliminated the problem. When I bought the car a few years ago, every gear was perfectly smooth even during shifts less coordinated.

I wonder if what I've heard of rusty spline or broken pressure plate spring cage is the culprit? Or worse... The actual gears?!