Vibration between 50 & 70 mph

[PipelineEngineer]

So they did the NVH and found an unknown origin frequency at 400Hz. The dealer is now trying to tell me all four tires need to be replaced. Road force balance values are Front 20 21 Rear 53 and 58. These are the Continental extremecontact dws06's with less than 5k miles.

Sponsored

 

[speedfrk]

So they did the NVH and found an unknown origin frequency at 400Hz. The dealer is now trying to tell me all four tires need to be replaced. Road force balance values are Front 20 21 Rear 53 and 58. These are the Continental extremecontact dws06's with less than 5k miles.

Have him swap a set of wheels off a car they know is good and see if the vibration goes away, it won't. 400Hz is very high for something wheel/tire related since it would be 24,000 RPM. You're dealing with complete idiots...

 

[PipelineEngineer]

I suggested that and they were quick to tell me they couldn’t/wouldn’t do that. I’m going to drill on it some more when I go pick it up tomorrow. 400hz is way to high for it to be tires

 

[GT Pony]

I suggested that and they were quick to tell me they couldn’t/wouldn’t do that. I’m going to drill on it some more when I go pick it up tomorrow. 400hz is way to high for it to be tires

Yeah, a tire vibration would be around 12~13 Hz at 60 MPH.

 

[Cobra Jet]

I suggested that and they were quick to tell me they couldn’t/wouldn’t do that. I’m going to drill on it some more when I go pick it up tomorrow. 400hz is way to high for it to be tires

Have you contacted a Regional CSR via the Ford 800#? If you haven’t then you need to do it and get a Case number started. Explain to the CSR what problems you’re having and tell the CSR you want them to pull a brand new set of wheels off another Mustang, put them on yours and YOU and the Tech go for a drive to prove and rule out it’s not your tires... Contacting Ford via the 800# and getting a Case established will bump your vehicle priority as well as your concerns. It will also document the issues and the Service Center will have to follow up with the CSR to status the repair efforts. If the Service Center is lacking in diagnosis techniques and doesn’t understand how to use the NVH tools, a FSE should be sent to that Service Center to assist with the repair efforts.

This specific 2015-17 NVH issue is NOT a tire concern, not a stock tire issue that the car came with or any tire that’s been installed since.

Demand they get an FSE out there to assist and make sure you open a Case.

 

[ABS550]

I suggested that and they were quick to tell me they couldn’t/wouldn’t do that. I’m going to drill on it some more when I go pick it up tomorrow. 400hz is way to high for it to be tires

Have a look at my posts on pages 118 and 119 of this thread. My vibration was typical of what is being complained about on this forum. It was measured at 48 Hz (by me) and was a driveshaft (driveline) imbalance. 400 Hz is a different animal altogether. I am not sure what would be turning at that speed, but it is worth investigating!

 

[Decosse]

Have a look at my posts on pages 118 and 119 of this thread. My vibration was typical of what is being complained about on this forum. It was measured at 48 Hz (by me) and was a driveshaft (driveline) imbalance. 400 Hz is a different animal altogether. I am not sure what would be turning at that speed, but it is worth investigating!

I suggested that and they were quick to tell me they couldn’t/wouldn’t do that. I’m going to drill on it some more when I go pick it up tomorrow. 400hz is way to high to be tires

I agree. On my follow up post 3515 on page 235, the included tech report stated Vertronix measured it at 42HZ.

 

[PipelineEngineer]

I have opened up a case with Ford Customer Service on Saturday and was supposed to hear back something today or Thursday. So it will probably be Thursday before I learn anymore about it. I really appreciate everyone's input on the situation and for the tip about reaching out to Fords Customer Service department. Happy New Years everyone!

 

[GT Pony]

So they did the NVH and found an unknown origin frequency at 400Hz.

Did their NVH analyzer see any other vibration frequencies? Could be that the 400 Hz they picked up is a result of something else being excited by a lower frequency source and resonating at 400 Hz.

 

[White Stallion 11]

Have you contacted a Regional CSR via the Ford 800#? If you haven’t then you need to do it and get a Case number started. Explain to the CSR what problems you’re having and tell the CSR you want them to pull a brand new set of wheels off another Mustang, put them on yours and YOU and the Tech go for a drive to prove and rule out it’s not your tires... Contacting Ford via the 800# and getting a Case established will bump your vehicle priority as well as your concerns. It will also document the issues and the Service Center will have to follow up with the CSR to status the repair efforts. If the Service Center is lacking in diagnosis techniques and doesn’t understand how to use the NVH tools, a FSE should be sent to that Service Center to assist with the repair efforts.

This specific 2015-17 NVH issue is NOT a tire concern, not a stock tire issue that the car came with or any tire that’s been installed since.

Demand they get an FSE out there to assist and make sure you open a Case.

Agree fully, and don't let up.

 

[barrykaye1001]

Take a look at my post #3456. It might help. Vibration between 50 & 70 mph

 

[barrykaye1001]

I am now in the same boat as the rest of you. I pre-ordered my car almost a year before taking delivery on it. 2015 mustang GT convertible, it is the first new vehicle I have ever had. The first 3-4 years and 20k miles were a dream. Car was smooth as glass. However in the past few months right before my warranty runs out the car has a very very annoying vibration 40-75mph range. We spent 2k on rims and tires because of some slight issues when they road forced balanced it an the vibration is still there. Now the service manager is trying to tell me this is normal for a convertible. I finally talked them into putting it on a NVH analyzer but he said he is highly doubtful it will find anything out of spec. I’m so pissed though because I loved this car and had every intention on keeping it as my weekend warrior for a long time. I’m a nuclear mechanical engineer and to have a Ford service manager tell me I don’t know what I’m talking about and to talk down to me like a child is infuriating. Also this is one of the largest mustang dealers in the entire US so it’s not like they can actually play dumb on this. And to think boomers wonder why millennials and gen z aren’t buying as many new cars. Lol... sorry guys I had to vent somewhere. I felt like I just flushed $60k down the toilet with this car...

It's not normal for a 'vert but you didn't flush $60k. It can be fixed. My '17 'vert had the same problem but now has almost 70k miles and is smooth as glass. Check out my post which details all that I went through to get mine fixed. Also, download an app called Shimmy Diagnoser. It's a simple NVH analyzer that uses the gyros in your phone to identify NVH sources. It gives you real data to show to the service department which, in my experience, they will pay attention to.

Ultimately, they need to check the runout of the driveshaft. They also need to use the MTS4100 NVH analyzer that uses sensors placed around the car to find NVH sources while driving. There is a redesigned driveshaft that helps. There is also a damper on the rear diff that Ford designed for the 2018+ model years. I don't have the damper but it might also help you.

Link to my post: Vibration between 50 & 70 mph

 

[PipelineEngineer]

After opening a case for Ford Customer service they reluctantly to finally agreed to swapping rims and tires from another car that they had to make sure didn't vibrate (according to them, i found this to be an odd comment) and low and behold they have sworn the vibration is gone and that the NVH analyzer now shows nothing. They want me to pickup the car tomorrow for a test drive before swapping my old rims and tires back on the car. I will push for an extended test drive but I have a feeling they will want to make a short around the block and have me accept that it is my rims and tires are the cause so they don't have to look any further into it. I am just so fed up at this point.

 

[PipelineEngineer]

So today has been fun. I went to pick it up from the ford of Murfreesboro dealer and as expected they wanted me to go for a short little test drive and while the car felt smoother the vibration was still there just not as pronounced as it originally was. So they take it back and put it back on the NVH analyzer after telling me I don't know what I am feeling and that it is normal blah blah blah. Then there with the new tires the NVH analyzer identifies a first order vibration between 35hz at ~30mph and 42 hz around 50-60mph that the scanner identified as 'wheel' and told me this was normal. Knowing this wasn't 'normal' at this point I realize they have no idea how to interpret the results of this machine, so being an engineer I dig into the elementary math of how frequencies and RPM work but this just goes way over their heads they instantly jump on the defensive by yelling at me about how I must be wanting a new drive shaft. I respond to this comment by stating I simply want my car to stop vibrating like my gf's vibrator at road trip worthy speeds. After much arguing they tell me they spoke to their regional ford engineer and determined this 35-42hz vibration is considered normal of convertibles and told me they will not investigate further unless I fix my tires. I know this doesn't make any sense but I have wasted so much of my day and so much times arguing with these idiots I reluctantly take my vibrating car back to discount tire where they road force balance them again and where they found high road force values they were half the values of what ford claimed them to be (using the exact same hunter force machines) and reluctantly agreed to replacing 3 of the four tires under warranty. The tires are on order and I will know Friday if this solves my problems but I highly doubt it. Btw at this point we have swapped out the wheels so many times Ford told me I had to replace my lug nuts to which I agreed to but damn with just 27,700 miles on the car this is the 6th set of tires and 3rd set of rims.

 

[GT Pony]

So today has been fun. I went to pick it up from the ford of Murfreesboro dealer and as expected they wanted me to go for a short little test drive and while the car felt smoother the vibration was still there just not as pronounced as it originally was. So they take it back and put it back on the NVH analyzer after telling me I don't know what I am feeling and that it is normal blah blah blah. Then there with the new tires the NVH analyzer identifies a first order vibration between 35hz at ~30mph and 42 hz around 50-60mph that the scanner identified as 'wheel' and told me this was normal.

From what I'm reading it seems to be wheel/tire related based on frequency. Seems like they no longer claim a 400 Hz NVH analyzer reading is present.

The tire shop needs to really look closely at wheel and tire radial and axial run-out too. A wheel/tire assembly can have excessive run-out and still show being adequately balanced. Some vehicles are more sensitive than others to wheels and tires.

Sponsored