Dentist drill sound coming from my new Novak AX-15

[MikekiM]

NV3550 to AX15 conversion went surprisingly well.

I am noticing a not so faint dentist drill sound once it gets warm. Only happens if I float the throttle around 2400 - 2600 RPM, regardless of the gear choice.
I used Redline SynchroMesh for break-in. Did a flush and replaced to the same gear lube after about 1000 miles.

Shifting is fine. Zero issues other than a mildly annoying whine. Would appreciate any thoughts you might have..

 

[Chris]

@NovakConversions

 

[MikekiM]

@NovakConversions

Thank you Sir!!

 

[Rickyd]

NV3550 to AX15 conversion went surprisingly well.

I am noticing a not so faint dentist drill sound once it gets warm. Only happens if I float the throttle around 2400 - 2600 RPM, regardless of the gear choice.
I used Redline SynchroMesh for break-in. Did a flush and replaced to the same gear lube after about 1000 miles.

Shifting is fine. Zero issues other than a mildly annoying whine. Would appreciate any thoughts you might have..

Which gear is it making a gear whine in?

 

[MikekiM]

Which gear is it making a gear whine in?

All gears.
Only when I am floating on the throttle and only around 2400 to 2500 rpm.
Lift off or depress the throttle and it goes away.
I can't feel anything amiss or anything change when the sound starts.
Not too loud, but audible.

 

[NovakConversions]

I'll get with my AX15 builder when he has a second and see what we can come up with. Stand by.

-Dustin

 

[NovakConversions]

Just got finished talking to my builder. For some reason, every time we have a customer with similar issues, it is always linked to them running redline. We haven't pinned down the difference yet but it is very common. We recommend switching to a different brand synchromesh and that has taken care of the problem. Hopefully that helps. If you switch and still have issues, please let me know.

-Dustin

 

[freedom_in_4low]

NV3550 to AX15 conversion went surprisingly well.

I am noticing a not so faint dentist drill sound once it gets warm. Only happens if I float the throttle around 2400 - 2600 RPM, regardless of the gear choice.
I used Redline SynchroMesh for break-in. Did a flush and replaced to the same gear lube after about 1000 miles.

Shifting is fine. Zero issues other than a mildly annoying whine. Would appreciate any thoughts you might have..

I don't see anything on Redline's website that calls itself Synchromesh. Are you referring to MTL or MT-90?

Just got finished talking to my builder. For some reason, every time we have a customer with similar issues, it is always linked to them running redline. We haven't pinned down the difference yet but it is very common. We recommend switching to a different brand synchromesh and that has taken care of the problem. Hopefully that helps. If you switch and still have issues, please let me know.

-Dustin

interesting. Mine isn't as "sharp" as a dentist drill but I do have a high mechanical whine sound that changes pitch with engine speed. It happens in both ranges but I notice it most in 4-low because I'm moving slow and there's not much other noise to contend with. I never considered it to be loud enough to worry about (and didn't actually notice it at all until the first time I wheeled) but it's there. I used MT90 because the Jeep FSM called for a 75W90 gear lube and everybody seems to love Redline.

 

[MikekiM]

Just got finished talking to my builder. For some reason, every time we have a customer with similar issues, it is always linked to them running redline. We haven't pinned down the difference yet but it is very common. We recommend switching to a different brand synchromesh and that has taken care of the problem. Hopefully that helps. If you switch and still have issues, please let me know.

-Dustin

I don't see anything on Redline's website that calls itself Synchromesh. Are you referring to MTL or MT-90?



interesting. Mine isn't as "sharp" as a dentist drill but I do have a high mechanical whine sound that changes pitch with engine speed. It happens in both ranges but I notice it most in 4-low because I'm moving slow and there's not much other noise to contend with. I never considered it to be loud enough to worry about (and didn't actually notice it at all until the first time I wheeled) but it's there. I used MT90 because the Jeep FSM called for a 75W90 gear lube and everybody seems to love Redline.

Sorry.. I just sent you guys on a goose chase.. I used Royal Purple SynchroMesh for break in and then again when I did the flush of the break in fluid. Sorry about that. I had Redline in the NV3550 and switched to Royal Purple based on feedback here.. IE.. lack of love for Redline.

The sound is loud enough that I am sure I could record it. It isn’t obnoxious but like most TJ owners, I know the sounds the Jeep makes and even the faintest will easily capture my attention. Loud enough that even the uneducated would ask… what’s that sound?

Definitely rpm specific. 2300 - 2700. Right in the sweet spot. Only when floating the throttle. As soon you lift or give it more gas it goes away.

@NovakConversion.. does this change your opinion ?

 

[NovakConversions]

Sorry.. I just sent you guys on a goose chase.. I used Royal Purple SynchroMesh for break in and then again when I did the flush of the break in fluid. Sorry about that. I had Redline in the NV3550 and switched to Royal Purple based on feedback here.. IE.. lack of love for Redline.

The sound is loud enough that I am sure I could record it. It isn’t obnoxious but like most TJ owners, I know the sounds the Jeep makes and even the faintest will easily capture my attention. Loud enough that even the uneducated would ask… what’s that sound?

Definitely rpm specific. 2300 - 2700. Right in the sweet spot. Only when floating the throttle. As soon you lift or give it more gas it goes away.

@NovakConversion.. does this change your opinion ?

No worries! If you could get a recording and send it over that might help narrow things down. My AX15 expert is out until Monday but I'll get with him then. You can send a video to me directly, dustin@novak-adapt.com. Or you are welcome to call in Monday and talk to him directly if you'd like, 435-753-2513

-Dustin

 

[MikekiM]

No worries! If you could get a recording and send it over that might help narrow things down. My AX15 expert is out until Monday but I'll get with him then. You can send a video to me directly, dustin@novak-adapt.com. Or you are welcome to call in Monday and talk to him directly if you'd like, 435-753-2513

-Dustin

Definitely can get a recording of it. I'll get it to you and I'll call in the afternoon on Monday.
thanks.

 

[Weasellee]

Curious what the outcome was…

 

[MikekiM]

Curious what the outcome was…

None yet. I have a good sound recording but haven't had time to call Novak.

Trying to get a read on when exactly it does it.

Drove home yesterday, like any other day, and it didn't make a sound. Can't lie.. the lack of whine was wonderful and the Jeep drove fantastic..

I keep rpms low when it's cold so. Won't hear it then.
And once it warms enough that I am cruising above 2500, I can hear it but inconsistently

If I drive it to work and park it for the day, it seems less likely that I will hear it on the drive home.

At this point, I am going to switch transmission fluid at the next oil change. I'll see what Novak suggests.

I have to stop procrastinating because it is going to be unbearable once the weather warms.

 

[NovakConversions]

None yet. I have a good sound recording but haven't had time to call Novak.

Trying to get a read on when exactly it does it.

Drove home yesterday, like any other day, and it didn't make a sound. Can't lie.. the lack of whine was wonderful and the Jeep drove fantastic..

I keep rpms low when it's cold so. Won't hear it then.
And once it warms enough that I am cruising above 2500, I can hear it but inconsistently

If I drive it to work and park it for the day, it seems less likely that I will hear it on the drive home.

At this point, I am going to switch transmission fluid at the next oil change. I'll see what Novak suggests.

I have to stop procrastinating because it is going to be unbearable once the weather warms.

We use Valvoline synchromesh in the shop when we run them.

Interesting, and I'm sure frustrating, issue you have. Did you ever get a chance to call in and talk to my AX15 builder? If not, he may be able to give you some ideas.

 

[machoheadgames]

I wouldn't call my AX15 quiet. What you're hearing is probably normal.

Doubt fluid makes much difference but I like to run 80W90 conventional GL4 in mine. Joe Gibbs Driven brand has been good for me. Might need to double clutch in the cold though as it's a bit stiff on a cold start...but it warms up quick.

 

[MikekiM]

We use Valvoline synchromesh in the shop when we run them.

Interesting, and I'm sure frustrating, issue you have. Did you ever get a chance to call in and talk to my AX15 builder? If not, he may be able to give you some ideas.

I haven't. I did make a few good recordings of it but I haven't been able to call.

I am coming up on an oil change and will probably try another fluid change but I am not terribly optimistic that will resolve it. I'll call before the week is out.

 

[MikekiM]

I wouldn't call my AX15 quiet. What you're hearing is probably normal.

Doubt fluid makes much difference but I like to run 80W90 conventional GL4 in mine. Joe Gibbs Driven brand has been good for me. Might need to double clutch in the cold though as it's a bit stiff on a cold start...but it warms up quick.

I don't think it is a normal sound. It's quite unique. Not a gear sound. Not a chatter. It's like a high pitched droning sound.. A whirling, bzzzzzz whine. Reminds me of a jet spooling up.

It's rpm specific but agnostic to which gear I am in. Hear it most in forth and fifth between 2200 & 2800. The slightest change in throttle position and it goes away. Can't feel it. No change in shifting or gear engagement.

If I were stone deaf I would have no idea when or if it were happening. Fortunately my hearing is good. When I open the window.. good lord. It's pretty loud when it's happening.

 

[machoheadgames]

I don't think it is a normal sound. It's quite unique. Not a gear sound. Not a chatter. It's like a high pitched droning sound.. A whirling, bzzzzzz whine. Reminds me of a jet spooling up.

It's rpm specific but agnostic to which gear I am in. Hear it most in forth and fifth between 2200 & 2800. The slightest change in throttle position and it goes away. Can't feel it. No change in shifting or gear engagement.

If I were stone deaf I would have no idea when or if it were happening. Fortunately my hearing is good. When I open the window.. good lord. It's pretty loud when it's happening.

Maybe input shaft/bearing noise since the input shaft always spins at engine speed. That could explain why it happens in the specific engine rpm range. Everything else is tied to wheel speed which obviously rises and falls separate from the engine.

 

[MikekiM]

Maybe input shaft/bearing noise since the input shaft always spins at engine speed. That could explain why it happens in the specific engine rpm range. Everything else is tied to wheel speed which obviously rises and falls separate from the engine.

That doesn't sound like something that can easily be resolved.. if at all.
Or that yet another fluid change will help.

 

[MikekiM]

Conversation today with Jared, the tech at Novak.
Fluid change won’t likely make a difference.
He thinks either pilot bearing or throw out bearing.

Really unfortunate because I’m not about to entertain pulling the transmission again