"mechanical whirl" or "mechanical growl on 97 NSX? tranny

[NSXknight]

Hello all.

I just bought a 1997 NSX yesterday from a member on prime. I luv the car. Car runs good but I did notice a noise from the transmission which the owner said was normal and was due to the double synchros working normally and he guranteed nothing is wrong with the noises thus I bought it.

I guess the noise is best described as a whirring or conk or growl sound?

Basically right after I shift to first the whir noise comes on for a second, than when I accelerate it comes on also for a second when I'm still in 1st. This same scenario also happens sometimes in 2nd.

Is this a normal noise for a 1997 NSX transmission? Or is this a mechanical issue that needs to be fixed?

The car also had a PPI done at an Acura dealer in Utah which it passed no problems. I will ask the mechanic if he heard the noise when he gets in this week.

I trust the owner as he is an outstanding member on NSX prime and S2ki board and a cool car guy but due to the car being expensive I want that extra confirmation before I drive it too much.


edit:

This noise occurs in all gears.

It only happens when your in gear and at about 1.5k-1.8k rpms, for example when I'm about to start cruising in 1st or reverse my rpms are pretty low and I get that wahh wahhh honk honk sort of sound. Would a tranny fluid change help that?

 

[Rtype1206]

Have you tried changing out the tranny fluid? Flush out the tranny first and then fill her up!

 

[NSXknight]

Have you tried changing out the tranny fluid? Flush out the tranny first and then fill her up!

Might try that but here is some more detail after testing........

This noise occurs in all gears.

It only happens when your in gear and at about 1.5k -1.8k rpms, for example when I'm about to start crusing in 1st or reverse my rpms are pretty low and I get that wahh wahhh honk honk sort of sound from the tranny I belive. Would a tranny fluid change help that?

 

[spider2k]

its a normal noise. mine makes it, my s2k made it. i just swapped my fluid with the gm syncromesh FM and its shifting smooth as butter also

 

[NSXknight]

its a normal noise. mine makes it, my s2k made it. i just swapped my fluid with the gm syncromesh FM and its shifting smooth as butter also

Nice Spider Do you know if there is a term or name for this issue? Anyone else have this same issue and it got solved by this?

I will try to schedule a fluid change this week than to see if that solves it or not. How and why does this correct the problem? Is this noise doing any mechanical harm or affecting performance?

 

[spider2k]

wont solve the noise. both my car always had it. the first time i rode in an s2k i could hear the tranny whirring and i thought it wsa gonna die cause it just sounded like it was winding out too far. once i got mine that had it too i realized it was normal. same with the nsx. you hear the tranny doing its job because its right there for you to hear.

 

[NSXknight]

wont solve the noise. both my car always had it. the first time i rode in an s2k i could hear the tranny whirring and i thought it wsa gonna die cause it just sounded like it was winding out too far. once i got mine that had it too i realized it was normal. same with the nsx. you hear the tranny doing its job because its right there for you to hear.

Thanks Spider! So it occurs in that very low rpm for every gear for you also when you hit the gas? It immeditely goes away after its 1.9-2+ or higher in the rev range.

I hope this is the same thing and maybe that is why the PPI mechanic didnt think it was an issue?

the noise is interesting as I thought it was a whirr but after more driving it sounds like a goose honk or even a short burst mechanical grind. I even told the owner aftr test drive that the gears sounded grinded in low rpm and he was like noooo it isn't that!!

 

[NSXknight]

Well I'm going to take it down to Zahtench who's an expert with an S2k/NSX shop here in the NW to test drive and hear the noise first hand. Hopefully the noises aren't an issue as Spider said but just in case the expert NSX mechanic hearing it in person will know for sure if it is or isn't an issue as tranny repairs are big $$$$.

 

[RON98]

hopefully its nothing. Hondas have been known to have the main shaft bearings go out quickly if the manual tranny fluid is not maintained at the proper level.

symptoms are

with the clutch in, no sound.

with the clutch out you'll hear like a warring sound. change fluid soon when you can hear this. it will not fix the problem but will prolong the issue.

in really bad cases... it will sound like a bucket of lose bearings rolling around in there and its bad at lower rpm.

usually its very quite. you actually have to actively listen for it to hear it. if your starting to hear it would out listening to it, I would check your tranny fluid.

not too many nsx make this noise. I haven't heard one yet.

Zahtench is way cool, he would be able to get you a better assessment of the issue when he takes it for a test drive.

happy motoring.

Rob:smile:

 

[NSXknight]

thanks Rob! In regard to the noise this doesn't sound too normal per my phone call with John today. I will probably take him to see it tommorow.

the whirrrrrrrrrr deep sound is noticable for sure.

hopefully its nothing. Hondas have been known to have the main shaft bearings go out quickly if the manual tranny fluid is not maintained at the proper level.

symptoms are

with the clutch in, no sound.

with the clutch out you'll hear like a warring sound. change fluid soon when you can hear this. it will not fix the problem but will prolong the issue.

in really bad cases... it will sound like a bucket of lose bearings rolling around in there and its bad at lower rpm.

usually its very quite. you actually have to actively listen for it to hear it. if your starting to hear it would out listening to it, I would check your tranny fluid.

not too many nsx make this noise. I haven't heard one yet.

Zahtench is way cool, he would be able to get you a better assessment of the issue when he takes it for a test drive.

happy motoring.

Rob:smile:

 

[nsxtcy85]

Pesky double syncro's

 

[NSXknight]

Thank you for everyone's help on this thus far, I really appreciate that as being a new owner and everyone so nice to help!!

 

[NSXknight]

NSX is now at Zahntech overnight for a hardcore deep dive tommorow. He agreed the noise isn't normal and perhaps could be a vibration from something loose but it could also be something mechanical hence the total search. Should have some type of answer by tomm evening.

I'm giving Mike Hale Acura a call tommorow on why they didn't advise me of the noise.

 

[NSXknight]

Finally got the answer

Thanks to Zahntech! Also others who posted!

Sound is coming from the exhaust system thus vibration from exhaust or header or cat converter. No biggie as I'm going aftermarket exhaust and header. The noise more concerned me with something was mechanically wrong!! Whew!!!

Zahntech also drove my NSX and the car checked out as running perfectly normal