2014 GT 6MT NVH at 60-70mph
8/20/13, 07:40 AM
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2014 GT 6MT NVH at 60-70mph
Hey everyone,
I picked up my 2014 just over a week ago, and from the start it has a noise/vibration issue when passing through the 60-70mph range. There is a low mechanical b-rrrrrrrrrrr noise regardless of gear or clutch position. It happens when accelerating onto the freeway, cruising at that speed, or coasting down through the speed range in gear or neutral. This makes me think it might be a bearing (wheel or axle). There is a slight vibration you feel in the steering wheel and the seat. It goes away over 70, but comes back north of 85mph. The noise over 85 is not that bad (or covered by engine/wind noise), but the vibration is more noticeable as the side mirrors become blurry.
The car has ~800 miles on it now. Already had it at the dealer once. They down force balanced the rear wheels, but that didn't fix the problem. Taking it in again today. Has anyone had something similar?
My buddy got a 2014 GT manual as well, and his is as smooth at 40 as it is at 80, and that's how I expect my car to be as well.
Thanks!
I picked up my 2014 just over a week ago, and from the start it has a noise/vibration issue when passing through the 60-70mph range. There is a low mechanical b-rrrrrrrrrrr noise regardless of gear or clutch position. It happens when accelerating onto the freeway, cruising at that speed, or coasting down through the speed range in gear or neutral. This makes me think it might be a bearing (wheel or axle). There is a slight vibration you feel in the steering wheel and the seat. It goes away over 70, but comes back north of 85mph. The noise over 85 is not that bad (or covered by engine/wind noise), but the vibration is more noticeable as the side mirrors become blurry.
The car has ~800 miles on it now. Already had it at the dealer once. They down force balanced the rear wheels, but that didn't fix the problem. Taking it in again today. Has anyone had something similar?
My buddy got a 2014 GT manual as well, and his is as smooth at 40 as it is at 80, and that's how I expect my car to be as well.
Thanks!
Last edited by Marcin K.; 8/21/13 at 10:50 AM.
8/20/13, 12:35 PM
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So I brought the car back for a second visit today. This time the service adviser came with me for a ride. He heard the noise right between 60-70, and decided that the shop foreman needs to take a lead on identifying the problem. Unfortunately the guy is on vacation for the next week and a half, so I'm stuck with till after the holiday weekend.
8/20/13, 03:45 PM
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Why would Ford put in a 2 piece driveshaft? Usually the 2 piece is reserved for very long cars when they want to raise the driveshaft resonant frequency. It costs more and adds more slop in the driveline. I see no advantage on our rather short cars.
mark
mark
8/20/13, 07:42 PM
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Wondered this myself. Never understood the purpose of a 2 piece Driveshaft in this car. However I do recall a relatively recent post on the forum about Ford having NVH with the S197. I believe in his post the Driveshaft was part of the fix according to this person. Have zero idea if it is true and not trying to spread a rumor. However it does kind of make sense.
8/21/13, 10:49 AM
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Well, the service adviser and I agreed that the issue is after the transmission, so drive shaft or rear axle. That doesn't really narrow it down too much. I'll wait till the foreman is back, and drop the car off for a few days. I'd hope they look at drive shaft, diff, axles and all the bearings, as well as wheel bearings.
8/21/13, 11:26 AM
#9
Mach 1 Member
Several of us have the identical issue you're chasing. Found here: https://themustangsource.com/f804/dr...-85mph-521314/
For what it's worth, I think you and your shop foreman are on the right track...
Keep us posted on what you find please.
Thanks,
John
For what it's worth, I think you and your shop foreman are on the right track...
Keep us posted on what you find please.
Thanks,
John
Last edited by Horspla; 8/21/13 at 11:29 AM.
8/21/13, 01:14 PM
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Yes. There could be an error in individual pieces. They have produced millions of these driveshafts without issue, but that doesn't mean they shouldn't be checked when running down a problem.
The 2 piece is for safety throughout the entire range of performance, in a number of different scenario's (including crash tests); the CV joint does not have roll in or clunk; and is designed to reduce NVH along with other parts of the "entire system". If people are having certain issues, then they are vehicle specific and need to be corrected.
I saved this to file from one of the S197 engineers on the Bullitt team that used to post here.
_____:Clunk is driven by total driveline lash, dominated by the gear sets and clutch tuning/capability. The 3.73 amplifies this a bit compared to the 3.31 and 3.55 axles. The 2-piece driveshaft is not the cause of the clunk noise. The Bullitt will have higher levels of clunk compared to the base GT. The base GT throttle response is a bit softer than the Bullitt's. The increased throttle response makes the clunk a bit easier to get. It is a trade-off - improved performance feel vs clunk.
_____:The post mentions high speed and 160mph - The Mustang (as it leaves AAI) is speed limited well below that for a reason. Like I said before, I do not know specifics about the dynotech piece, what it does or does not do. I do know about the 2-piece in the factory car. It is a fairly robust piece. Vibration is not an issue unless the centerbearing shims are not installed properly, the shaft has a balance issue or the pinion angle is off. These would be quality issues (that I'm not aware of having in production), not design. The 2-pc has no roll in whether or not you have a random vibration. U-joint angles, run-out (flange or shaft), balance and system modal (resonance) response govern vibration.
2 piece drive shaft
The 2-piece driveshaft is required to meet internal engineering requirements for safe operation at max vehicle speed. Basically, it is designed to provide a driveline system resonance well above what the speed limiter will allow you to operate at. If you put your driveline into resonance, bad things may happen! I've seen what it does to a car and it isn't pretty.
The driveshaft CV joints are required components on this type of driveshaft when combined with a live axle. If the rear suspension were IRS, simple flex couplings would be used (look at the new Camaro, Challenger, etc...) and would make for a lighter driveshaft.
The driveshaft also has an internal torsional damper (ITD) which is soley there to attenuate axle whine. If package allowed, the ITD would be mounted on the exterior of the driveshaft as a much lighter ring design. Since the equivalent inertia is required out of the smaller diameter part when installed inside the driveshaft, the mass has to increase. So, you get a heavier ITD vs a lightweight ETD.
A single piece steel or aluminum 1-piece would have to be larger in diameter than the current package allows. Basically, you would have contact with the fuel tank at full rear suspension jounce. 1-piece carbon fiber was explored at one time...
Hope this helps.
*****
I would not assume an aftermarket piece "solves" a problem. Yes, you can stuff a massive driveshaft into the tunnel but it will not meet standard vehicle engineering requirements. Our requirements take many factors into account, with the biggest one being your personal safety under a wide variety of operating conditions. Our parts are engineered to work in one big system. Aftermarket parts are generally not engineered. By this, I mean that they are designed to fit properly (usually) and improve one or two attributes specific to your application.
For example, if you want a lighter weight driveshaft that gives you less rotating inertia, you can buy this aluminum 1-pc driveshaft. But, that's all you get - lighter weight. Not proven durability, safety (how does the driveshaft react in a rear impact?, clearance to other parts like the fuel tank?), NVH, ride (driveshaft plunge force actually affects your ride quality), etc...
But that's the great part about it being your car. You get to decide what you want your Mustang to be. Just be cautious and think about how these parts may affect the rest of your driving experience, safety and wallet if it breaks or breaks something else in the car.
I've been in your shoes (which is why I became an engineer and worked my way onto the Mustang team!) and know exactly where you are coming from, though. I don't know specifics about the d/s you are referring to but I'm just giving you some things to think about and consider.
Thanks for buying a Bullitt!
*****
lower control arm bracket axle masses
They are there to attenuate axle whine. If you currently notice axle whine in your car in the 45-65mph range, it may increase a bit if you remove the masses. They are one part of a fairly extensive package engineered to address axle whine on the s197 platform.
> Hope you get the problem figured out. I have no harmonics/vibration at any speed range, the ride is quiet enough to hear the factory exhaust with the windows closed, what little clunk I get (typically over bumps in my dirt road from the ranch to the highway or going over speed bumps if I'm not squared up) is from the clutch packs working in the track-lock differential to reduce tension/bind on one wheel. I could be wrong, but I think a number of newer Mustang drivers have not driven a track-lock diff before. They are not noise free.
Regardless, drivers should not have vibration at different speed ranges. Good luck!
Wondered this myself. Never understood the purpose of a 2 piece Driveshaft in this car. However I do recall a relatively recent post on the forum about Ford having NVH with the S197. I believe in his post the Driveshaft was part of the fix according to this person. Have zero idea if it is true and not trying to spread a rumor. However it does kind of make sense.
I saved this to file from one of the S197 engineers on the Bullitt team that used to post here.
_____:Clunk is driven by total driveline lash, dominated by the gear sets and clutch tuning/capability. The 3.73 amplifies this a bit compared to the 3.31 and 3.55 axles. The 2-piece driveshaft is not the cause of the clunk noise. The Bullitt will have higher levels of clunk compared to the base GT. The base GT throttle response is a bit softer than the Bullitt's. The increased throttle response makes the clunk a bit easier to get. It is a trade-off - improved performance feel vs clunk.
_____:The post mentions high speed and 160mph - The Mustang (as it leaves AAI) is speed limited well below that for a reason. Like I said before, I do not know specifics about the dynotech piece, what it does or does not do. I do know about the 2-piece in the factory car. It is a fairly robust piece. Vibration is not an issue unless the centerbearing shims are not installed properly, the shaft has a balance issue or the pinion angle is off. These would be quality issues (that I'm not aware of having in production), not design. The 2-pc has no roll in whether or not you have a random vibration. U-joint angles, run-out (flange or shaft), balance and system modal (resonance) response govern vibration.
2 piece drive shaft
The 2-piece driveshaft is required to meet internal engineering requirements for safe operation at max vehicle speed. Basically, it is designed to provide a driveline system resonance well above what the speed limiter will allow you to operate at. If you put your driveline into resonance, bad things may happen! I've seen what it does to a car and it isn't pretty.
The driveshaft CV joints are required components on this type of driveshaft when combined with a live axle. If the rear suspension were IRS, simple flex couplings would be used (look at the new Camaro, Challenger, etc...) and would make for a lighter driveshaft.
The driveshaft also has an internal torsional damper (ITD) which is soley there to attenuate axle whine. If package allowed, the ITD would be mounted on the exterior of the driveshaft as a much lighter ring design. Since the equivalent inertia is required out of the smaller diameter part when installed inside the driveshaft, the mass has to increase. So, you get a heavier ITD vs a lightweight ETD.
A single piece steel or aluminum 1-piece would have to be larger in diameter than the current package allows. Basically, you would have contact with the fuel tank at full rear suspension jounce. 1-piece carbon fiber was explored at one time...
Hope this helps.
*****
I would not assume an aftermarket piece "solves" a problem. Yes, you can stuff a massive driveshaft into the tunnel but it will not meet standard vehicle engineering requirements. Our requirements take many factors into account, with the biggest one being your personal safety under a wide variety of operating conditions. Our parts are engineered to work in one big system. Aftermarket parts are generally not engineered. By this, I mean that they are designed to fit properly (usually) and improve one or two attributes specific to your application.
For example, if you want a lighter weight driveshaft that gives you less rotating inertia, you can buy this aluminum 1-pc driveshaft. But, that's all you get - lighter weight. Not proven durability, safety (how does the driveshaft react in a rear impact?, clearance to other parts like the fuel tank?), NVH, ride (driveshaft plunge force actually affects your ride quality), etc...
But that's the great part about it being your car. You get to decide what you want your Mustang to be. Just be cautious and think about how these parts may affect the rest of your driving experience, safety and wallet if it breaks or breaks something else in the car.
I've been in your shoes (which is why I became an engineer and worked my way onto the Mustang team!) and know exactly where you are coming from, though. I don't know specifics about the d/s you are referring to but I'm just giving you some things to think about and consider.
Thanks for buying a Bullitt!
*****
lower control arm bracket axle masses
They are there to attenuate axle whine. If you currently notice axle whine in your car in the 45-65mph range, it may increase a bit if you remove the masses. They are one part of a fairly extensive package engineered to address axle whine on the s197 platform.
> Hope you get the problem figured out. I have no harmonics/vibration at any speed range, the ride is quiet enough to hear the factory exhaust with the windows closed, what little clunk I get (typically over bumps in my dirt road from the ranch to the highway or going over speed bumps if I'm not squared up) is from the clutch packs working in the track-lock differential to reduce tension/bind on one wheel. I could be wrong, but I think a number of newer Mustang drivers have not driven a track-lock diff before. They are not noise free.
Regardless, drivers should not have vibration at different speed ranges. Good luck!
Last edited by cdynaco; 8/21/13 at 01:21 PM.
8/24/13, 04:29 PM
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Drive Train Vibration
New here. Maybe this belongs elsewhere. I took delivery of my 2014 MCA performance package, manual, 10 months ago. It has 14,000 miles now. Love the car. From the beginning I get a pretty healthy intermittent vibration on deceleration between 3000 and 2000 rpm. I can feel it in the shifter and in the seat. Had the service manager drive the car, it did it for him. He said it was new to him and would research. I have not been back yet. I suspect the clutch. Newton's ideas on physics did not like vibrations. Any ideas or a reference.
TB
TB
8/25/13, 08:44 PM
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New here. Maybe this belongs elsewhere. I took delivery of my 2014 MCA performance package, manual, 10 months ago. It has 14,000 miles now. Love the car. From the beginning I get a pretty healthy intermittent vibration on deceleration between 3000 and 2000 rpm. I can feel it in the shifter and in the seat. Had the service manager drive the car, it did it for him. He said it was new to him and would research. I have not been back yet. I suspect the clutch. Newton's ideas on physics did not like vibrations. Any ideas or a reference.
TB
TB
NVH issues are hard to diagnose. Perhaps we're experiencing the same thing, but perhaps not. Either way, I thin your local Ford service is in the best position to try to diagnose it.
Perhaps this is a standard level of NVH variance in Mustangs. I'm just worried that it's a symptom of a larger problem, and it will increase over time. If it's not, I could live with my muscle car making a bit of noise. Either way, I want to know for sure and I think Ford Service is in the best position to make that determination.
8/26/13, 05:42 AM
#13
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EDIT: Oops, cdynaco gave the full scoop on that in his post above!
Last edited by Tony Alonso; 8/26/13 at 05:46 AM.
8/26/13, 06:17 AM
#14
Cobra Member
New here. Maybe this belongs elsewhere. I took delivery of my 2014 MCA performance package, manual, 10 months ago. It has 14,000 miles now. Love the car. From the beginning I get a pretty healthy intermittent vibration on deceleration between 3000 and 2000 rpm. I can feel it in the shifter and in the seat. Had the service manager drive the car, it did it for him. He said it was new to him and would research. I have not been back yet. I suspect the clutch. Newton's ideas on physics did not like vibrations. Any ideas or a reference.
TB
TB
Last edited by JCStang; 8/26/13 at 06:48 AM.
8/26/13, 06:03 PM
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It's the dual mass flywheel, all manual V6's have it...there should be some threads out there regarding this issue...mines done it since day 1....
Marcin K and Jeff,
Thanks for the reply, after time I would think that the input shaft splines and clutch disc hub would ware inordinately. I'll stop back and visit with the service director and see what he has to say. If anyone has a link to a chat about this issue please advise.
TB
Marcin K and Jeff,
Thanks for the reply, after time I would think that the input shaft splines and clutch disc hub would ware inordinately. I'll stop back and visit with the service director and see what he has to say. If anyone has a link to a chat about this issue please advise.
TB
9/3/13, 01:25 PM
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Quick update: the chief mechanic is back at the dealer, so they gave me a call last week and said he's ready to work on my issue. I dropped off the car again today. I hope to have more news in a day or two. Keeping my fingers crossed.
9/6/13, 09:40 AM
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New here. Maybe this belongs elsewhere. I took delivery of my 2014 MCA performance package, manual, 10 months ago. It has 14,000 miles now. Love the car. From the beginning I get a pretty healthy intermittent vibration on deceleration between 3000 and 2000 rpm. I can feel it in the shifter and in the seat. Had the service manager drive the car, it did it for him. He said it was new to him and would research. I have not been back yet. I suspect the clutch. Newton's ideas on physics did not like vibrations. Any ideas or a reference.
TB
TB
Deysha
9/6/13, 10:30 AM
#18
Hello and welcome, UB.3! My name is Deysha with Ford Service. I recommend you make an appointment with your dealer, and let me escalate this to the customer service manager for your area. Please, PM me with your VIN, dealer, mileage, full name, and best daytime number.
Thank you for the update, Marcin K.
Deysha
Thank you for the update, Marcin K.
Deysha
Thanks for all you do..
9/9/13, 10:47 AM
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Ok, another update on this topic. Ford dealer had the car for 4 days, and they even had a Ford service engineer take a look at the car. They ground force balanced all 4 tires, took the drive shaft out of the car, and inspected the shaft and the connecting joints. No out of spec issues were identified there. The Ford service engineer said that it's within normal range, and as good as it can get without tearing apart the rear end of the car. 
So my issue is still not resolved, but at least I know it's not a symptom of a larger problem lurking around the corner.
The good news is that over the last 1400 miles the vibration reduced significantly, and now it's very faint and barely noticeable. The noise it creates is the only thing still persisting, but I'm OK with my muscle car making a little bit of noise.
So I have peace of mind knowing it's not a wheel bearing about to lock up a wheel on me, and in all honesty the noise levels are acceptable to me. Now I also know the drive shaft is not the issue, and I can get back to enjoying my new Mustang.
And Thank You to Deysha for elevating it, and getting me in touch with the regional Ford rep.
Even though it is a bit disappointing that there is no solution to this, at least I do feel that the dealer and Ford did everything they could within reason to address my concerns. And for that I am grateful.
Good luck to everyone still dealing with similar issues.
So my issue is still not resolved, but at least I know it's not a symptom of a larger problem lurking around the corner.
The good news is that over the last 1400 miles the vibration reduced significantly, and now it's very faint and barely noticeable. The noise it creates is the only thing still persisting, but I'm OK with my muscle car making a little bit of noise. So I have peace of mind knowing it's not a wheel bearing about to lock up a wheel on me, and in all honesty the noise levels are acceptable to me. Now I also know the drive shaft is not the issue, and I can get back to enjoying my new Mustang.
And Thank You to Deysha for elevating it, and getting me in touch with the regional Ford rep.
Even though it is a bit disappointing that there is no solution to this, at least I do feel that the dealer and Ford did everything they could within reason to address my concerns. And for that I am grateful. Good luck to everyone still dealing with similar issues.
Last edited by Marcin K.; 9/9/13 at 10:49 AM.