6 Speed Smoothness

[Sportsrod]

I’m the 3rd owner of a 02 NSX I bought back in April and I’m not real satisfied with the smoothness of my 1st to 2nd gear upshifts. I have to be very slow & deliberate when upshifting into 2nd gear otherwise it has a tendency to grind. I have no other 6 speed owners in my area to compare with, and my local ACURA NSX tech tells me this is an inherent 6 speed design characteristic. I’d like an absolutely honest opinion about the ease and smoothness of your car’s 2nd gear upshifts. Interestingly, I don’t have an issue with 3rd to 2nd downshifts. They seem to always be smooth and easy.

My car is still under warranty and I’m wondering if I need to pursue some warranty work to my transmission. It’s just that I hate to have anyone work on my cars unless absolutely necessary. Thanks for your reply.

 

[NsXMas]

Get a second opinion. My 6 speed is very smooth when shifting to all the gears - there is no grind whatsoever.

Your local Acura NSX tech is out of his mind.

If the NSX 6 speed transmission grinds as an "inherent" characteristic it would be a serious flaw.

And get another tech to work on it. Ask nsxtasy for recommendations since he is close to you.

 

[Synthesis]

just get it done.... it's under warranty. wish i had that luxury

 

[OLDMNSX]

Sportsrod, Something that I have learned from other members here on Prime, is that General Motors makes a manual transmission fluid called "SyncroMesh" and also "Friction Modifer" the general consensus seems to be 2 qt SyncroMesh and 1 qt Friction Modifer. Some of the guys claim that it made a world of difference in how their transmission shifted.

This is something that you could do yourself and see if it helps. I purchased three quarts when I was home for leave in October and if I remember right it was like $25 for all of it.

Drive the car for 20-30 miles, to warm it up, and then remove the fill plug and the trans drain plug, let it drain over night. I use a normal funnel and a piece of clear plastic tube to refill. Take the fill plug with you to the hardware store to get the right size tube. Reinstall the drain plug. If you warm up the fluid it flows faster. If it is warm where you are sit it in the sun for a couple hours or in front of the wood stove.

It is easier if you remove the left rear wheel. Do your best to keep the car level. You can't over fill the transmission. It will just run out of the fill port. Be sure to have a catch pan under the fill port.

It may be worth a try. It sure beats having the transmission taken out. I don't care if it is still under warranty.

I see from your avitar that you will probably be using the wood stove to warm it up!

Brad

 

[Maximus_NSX]

I have read about this exact problem with other NSX's. In fact, my 03 does the same. It feels a bit "notchy" when shifting from 1st to 2nd. It doesnt have the tendency to grind, but it is not as smooth as my other gear changes. I have also read that as the car warms up, it gets smoother. You can look up NSX member Turbo2go. He will say the same thing about his 05 NSX.

 

[nsxtasy]

There's a difference between the shifter being "notchy", which is normal for the six-speed, and a grind or crunch getting it into gear. If it's really grinding/crunching, it may be that the teeth on the hub selectors or synchros are worn. Some people have found that the symptom can be reduced with the Synchromesh transmission fluid; that may be worth a try. The problem with fixing it (if it is indeed crunching) is that you need to open up the transmission, which means 8-12 hours of labor - so other than changing the fluid, you may be better off living with it unless it gets really bad or until you need other transmission work (e.g. clutch replacement). OTOH, since your car is under warranty, I would get it checked out before the warranty runs out. The first thing I would do, though, is to try driving someone else's six-speed NSX, to see if it feels the same as yours.

And get another tech to work on it. Ask nsxtasy for recommendations since he is close to you.

Actually, I'm at the other end of the state. But there are quite a few NSXers near you in the St. Louis area that can recommend a good tech.

There's a new owner in the St. Louis area with a six-speed - maybe you can contact him to see if you guys can get together and swap cars, see if they feel the same.

Also, as another option, if you are interested, feel free to join the NSX Club of America and come to our annual dinner on March 24 (click here for details). There will likely be some six-speeds there and maybe someone will let you drive his. Last year, a couple of the guys from St. Louis drove up to join us.

 

[poncekim]

I have the same "issue". I have an 04 with 7K miles, and I noticed this notchyness going into second gear as well. When the engine is cold, there is even a slight grinding. This pretty much goes away after the engine is warmed up.

Do a search - you will find many owners with the same experience. I've seen enough people mentioning this issue to think the tech is right, and it's something most of us have.

 

[BD]

First off, before the car is warmed up, the First to Second transision is very "tight." Lots of people notice it, but once the engine is warmed up, it is probably one of the smoothest transmission out there.

 

[The Kid]

First off, before the car is warmed up, the First to Second transision is very "tight." Lots of people notice it, but once the engine is warmed up, it is probably one of the smoothest transmission out there.

Vance,

Is your S2000 like that as well? Mine grinds second when cold:frown:

 

[KSXNSX]

I am going to confirm the notchy and "tight" 1->2 upshift. It is bad when cold, and gets better as it warms up.

However, I have never had a problem with grinding.
(2004 6 speed)

My personal opinion is to decide if it is just notchy or if it is grinding. If it is just notchy, I don't recommend pursuing a fix for the transmission. Even IF you can get them to do a warranty repair job (which they probably will oppose), it has been my personal experience that you can't really trust what they are doing to your car when it is out of your sight. Of course this all depends on the dealership, so just be cautious.

 

[Sportsrod]

I've read some previous threads on this subject but I don't understand how NsXMas can have a 6 speed transmission that upshifts into 2nd gear so smooth, while Maximus, poncekim, Vancehu, and I, have the notchy, tight, binding 2nd gear. Guys, why isn't our transmission upshifts smooth, if smooth upshifts are possible? What do we have out of adjustment, or worn that the other guys don't?
This is why I posted this thread. First to know if my upshift problem was a known inherent design issue, but if other 6 speed owners don't have the same notchiness then there must be an adjustment, rigging, or clearance out of tolerance in our notchy 6 speeds.
Has anyone out there ever fixed this issue beyond the GM Synchromesh & Friction Modifier route?

 

[kye]

I have a 98 and 2nd gear can be quite notchy when cold, my ealier model S2000 had the same problem but more pronounced than in the NSX
//Kye

 

[comtec]

I've read some previous threads on this subject but I don't understand how NsXMas can have a 6 speed transmission that upshifts into 2nd gear so smooth, while Maximus, poncekim, Vancehu, and I, have the notchy, tight, binding 2nd gear. Guys, why isn't our transmission upshifts smooth, if smooth upshifts are possible? What do we have out of adjustment, or worn that the other guys don't?
This is why I posted this thread. First to know if my upshift problem was a known inherent design issue, but if other 6 speed owners don't have the same notchiness then there must be an adjustment, rigging, or clearance out of tolerance in our notchy 6 speeds.
Has anyone out there ever fixed this issue beyond the GM Synchromesh & Friction Modifier route?

I have an 02 and have the same notchy feeling when shifting from 1st to 2nd when cold. Apparently NsXMas just doesn't realize it. Since everyone else notices the same thing i believe that is just the way it is. It is not a problem.

 

[BD]

Vance,

Is your S2000 like that as well? Mine grinds second when cold:frown:

I don't remember the whole detail, so you have to look into it.

When I had my 01 S2k, there was a recall/Update on the transmission. It had sycro problems. Honda rebuilt my whole transmission under Honda Care and the bill was over 3 grand. They replaced all of the syncros.

You may still have Honda honor the recall if it is related. I didn't have problem with second grear, but I couldn't get into fift gear. If I can get it in there, it will pop out of the fifth while driving.

Good luck

As far as I know, the AP2 S2ks are all free of tranny problems.

 

[RPM217]

I made the same post years ago, when I first got my 02. I even brought it back to the dealer and questioned it. They checked it out and told me that it was normal. After the car is fully warmed up, it's smooth as butter, but until then 1-2 is "notchy" and until confirmed that it's normal, I was cautious. Now, before I start "pushing" the car and doing rapid, high rev shifts, I make sure the car is properly warmed up, including the transmission!!!

 

[The Kid]

You may still have Honda honor the recall if it is related.
Good luck

As far as I know, the AP2 S2ks are all free of tranny problems.

Yea, like that's ever gonna happen. I can just imagine pulling into the service dept. with that huge front mount. I dont think Honda's gonna warranty the tranny on a 400 horsepower beast, but I'll certaintly try.:biggrin:

 

[BD]

Yea, like that's ever gonna happen. I can just imagine pulling into the service dept. with that huge front mount. I dont think Honda's gonna warranty the tranny on a 400 horsepower beast, but I'll certaintly try.:biggrin:

lol, that's a different story. Good luck:smile:

 

[Todd McKelvie]

I have an 02 with 38k miles...I live in Southern California....it is my daily driver. When the weather got cold (40 degrees in the am) a couple months back, I started getting the same problem. So...it seems to be a temp issue. To fix the "grind into 2nd" when it is cold, I do the following.

1. Let it warm up a couple minutes longer.
2. Drive the first mile slow and shift like the following.
3. When I shift from 1st to 2nd, I shift out of 1st...let it go into neutral...move it to the right and then back to the left...and then into second.

After a mile or so, the grind is gone. Try it...it may work for you?

 

[OLDMNSX]

Guys, I can feel for your situation. Just knowing how the transmission is linked to the shifter, I would:

1. Verify that the shift cables are correctly rigged. They don't move very much, so rig can be very important.

2. When the engine / trans are cold shift from 1st to 2nd at a lower RPM and try to match engine RPMs to the trans speed.
i.e. If in first gear at 20 mph the RPMs are 2000 and second gear at 20 mph the PRMs are 1500 then when shifting from 1st to 2nd allow the RPMs to drop only 500 RPMs as you shift. Avoid allowing the RPMs to drop all the way off to idle. This will make the 1st to 2nd gear syncro have to adjust speed very little. Kind of like driving the old Ken Worth truck on the farm. It didn't have syncros on any of the gears!

3. Has anyone with this 6-Speed situation tried the Syncro-Mesh fluid?

Brad

 

[favetita]

I have a 2000 with 52,xxx miles. The upshift from 1st to second is notchy. Grinding happens especially when the weather is cold. I have to be really careful and deliberate making this initial shift, pausing in neutral and leaning heavily on the left to guide shift into second from first. Grinding happens only once, during this "initial" shift and never happens twice on the same drive with the quality of shift feeling better as the engine and transmission warms up. Second to third shift goes "click-click", with 3-4-5-6 shifts going in smooth. I'm thinking of trying the GM concoction next year when I'm up for a trans fluid change but really reluctant to use anything that says GM for the NSX.

 

[NSXGMS]

I've read some previous threads on this subject but I don't understand how NsXMas can have a 6 speed transmission that upshifts into 2nd gear so smooth, while Maximus, poncekim, Vancehu, and I, have the notchy, tight, binding 2nd gear. Guys, why isn't our transmission upshifts smooth, if smooth upshifts are possible? What do we have out of adjustment, or worn that the other guys don't?
This is why I posted this thread. First to know if my upshift problem was a known inherent design issue, but if other 6 speed owners don't have the same notchiness then there must be an adjustment, rigging, or clearance out of tolerance in our notchy 6 speeds.
Has anyone out there ever fixed this issue beyond the GM Synchromesh & Friction Modifier route?

Just to clarify have we determined whether this is a "notchiness" or a "grind"? If there's grinding of any kind then I would agree there are probably worn teeth on the hub selectors or synchros. Great opportunity for a full rebuild with a Type-R 4.235 final drive particularly if it's under warranty.

If it's strictly a "notchiness", particularly when cold, that appears to be an unusual but not entirely uncommon phenomenon based on other 6-speed owner's responses. Since it's unlikely to get a warranty OK for a full rebuild based on those "notchy" symptoms alone I would recommend the GM Synchromesh fluid.

The formula is 1 quart GM Synchromesh [GM part # 12345349] and 2 quarts Friction Modified [GM part # 12377916].

I've been using it for 2 years and it made a noticeable difference in the smoothness of my tranny. I have a 91 and have never had a rebuild. See this thread regarding it's results.

 

[Ben]

My '05 grinds on the 1-2 shift for the 1st 5-10 mins after a cold start. After that, it's fine. Haven't had time to take it in to have it looked at though. Other '05 owners have reported the same issue.

 

[evel333]

I have a 2000 with 52,xxx miles. The upshift from 1st to second is notchy. Grinding happens especially when the weather is cold. I have to be really careful and deliberate making this initial shift, pausing in neutral and leaning heavily on the left to guide shift into second from first. Grinding happens only once, during this "initial" shift and never happens twice on the same drive with the quality of shift feeling better as the engine and transmission warms up. Second to third shift goes "click-click", with 3-4-5-6 shifts going in smooth...

My situation is almost identical - I don't experience any grinding, but the notchy feeling and sounds have bothered me since day one. Also seems to feel smoother at higher RPM and hard acceleration. (an "inconvenience," I'm sure)

My previous car was a 2004 S2000, so my comparisons regarding transmission smoothness were immediate. I'm sure other AP2 S2K owners can vouch for this.

 

[Todd McKelvie]

Has anyone resolved this notchy/grinding issues with their NSX? How can so many people have issues with the transmission of a $80,000 car? It seems like most of the issues are coming from 02 and newer.

I have had everything looked at...3 different times, except completely dismantle the transmission and replacing all the gears! I LOVE my NSX...HATE the shifting!!!

My first car was a 1981 Honda Accord and that transmission was 100x better than the piece of crap on my 02...not to mention I paid a whopping $8,500 for my Accord and have over $75,000 into my NSX.

There is absolutely NO way this is normal. I don't care how many "technicians" say it is, Honda would NEVER knowingly put out a product this SHITTY!

If anyone knows anybody at Honda America, please forward their contact info to me. We need to UNITE and get this inherent problem fixed by Honda....free of charge. Any ideas????

 

[MCM]

Sounds like maybe a syncro issue?
(So, it does not change when warmed up?)
I would not want to tear into it just yet.
Try some Lucas Heavy Duty Oil Stabilizer (drain a bit out & add)
& call me in the morning.
I would try this prior to going into your trans.