S2Driver

My S2 is sick again.

First four gears, and sixth gear are all working smoothly without any grinding.

Fifth gear was stiff from new and couldn't be used at 4K miles(Severe grinding). Sixth gear worked fine. Dealer changed fifth/sixth syncro rings, hubs and fork. Fifth gear was still stiff after the work, and now it has the same problem at 9K miles.

It appears that because the gear selection is stiff, the forks bend, and fifth gear can't be engaged. I didn't miss shifts, or abuse the transmission, although it is driven aggressively like a sports car should be.

Do other S2s have this problem?

Is there a logical technical explanation?

Is there a Honda recall on fifth gear?

Any help would be appreciated.

S2Driver '00S2

VTEC Racer

I'm completly locked out of 5th gear. It has never grinded though. 6th gear grinds heavily though. Don't know why 5th got messed up. The parts come in for my car on Friday, and thats when they will start the work. They are replacing 1st, 2nd, 5th, and 6th gear. 2nd gear grinds on my car, and 1st got messed up too even though it has never grinded. I guess they are connected some how or something.

S2Driver

VTEC Racer

That's the fix I had last year. The 1st/2nd work was the recall for grinding during high rpm shifts. The 5th/6th was for not being able to put it into 5th. Is the dealer replacing the 5th/6th shift fork?

They also put in the upgraded tranny fluid, which substantially improved the shifting smoothness.

By the way what type of racing do you do; street, solo, road?

S2Driver

smyroad

My tranny is smooth in any gear with an occasional 1-2 grind. If you're having difficulty something's definitely wrong. It could be the transmission, but it could also be a clutch not completely disengaging or maybe a bad throw out bearing.

Roceye

If I ever have a trans problem that is covered under warranty, I will not let the dealership "fix" the trans. I will make them replace the whole unit. The reason being this, Honda pays their techs too little to take their time with this type of job. A internal repair to a S2000 trans requires alot of measuring and test fitting parts together to make sure it's assembled correctly..

The Dealer repair environment does not foster this type of atmosphere, so if I ever have a trans problem that is out of warranty, I will repair it myself (it helps that I'm Auto tech).

S2Driver

Reviewing the Honda S2000 Service Manual, the transmission has double cone synchros in each of 1st to 4th gears, to help match gear rpm at 9K rpm.

Fifth and sixth gear have single synchros. It appears the fifth and sixth gear don't have the capability to match gear rpms as well as 1st to 4th.

So if the shift to 5th is quick at high rpm, the shift fork will bend (over a number of shifts), resulting in the transmission not being able to go into fifth (it grinds, and won't go into gear). Sixth works fine although it uses the same shift fork (wouldn't 6th have problems too?).

Fourth gear at 9K rpm is at 116mph, so I expect Honda didn't expect S2K owners to drive that hard, so they designed with a single synchro for fifth gear.

The conclusion is to baby your shifts into 5th and 6th.

Does anyone have any more info, or can confirm this?

Vtec Racer, what did Honda change to fix your fifth gear problem?

Woodward, any ideas?

Roceye

I think the reason for #5 and #6 syncros only having one cone is the fact that the mass of the #5 and #6 gearsets are less than the other gearsets. Therefore they require less friction to syncronize speeds with their respective shafts and don't need the extra cone.

nine grand

I have had a 5th grind twice now. It's not a bone jarring, earth stopping grind, but you can here the gears are just about to rip each other apart. The first time I think it was driver error, but the second time I'm not so sure. Kinda worried now. I though it was just my car acting up but if you guys are having the same problem then there may be something wrong.

S2.001K

I had my 5th gear fail a couple months ago. Everything was peachy until one night I was shifting into fifth and heard this horrible grinding sound. After the grind i could no longer get into 5th gear. I set up an appointment for the following week for service and drove it only a few times before my service appointment. In those few drives i additionally lost 6th gear and almost reverse(hard to engage)
The dealership did an excellent job, overnighted the parts, and i haven't had any problem since (knock on silicon) I posted a thread at the time but it seemed like nobody else had the problem.

bill

jalbrah

Honda will never replace the entire tranny if it is you only have a bad 5th gear synchro.... the tranny on the S2k must cost a little fortune...

The changes in transmission for the MY 02 reflect the fact that Honda has acknowledged a problem with the transmission on earlier S2Ks. I just don't understand why they did not make the change for the MY 01 since there was quite a few problems reported with the MY 00...

All I can say, is that I am glad that I waited for the MY 02


Good luck with your car and keep us posted.