Vibration between 50 & 70 mph

[Rickloreto]

Interesting .,.. first time I've heard of this procedure to reset the BMS.

Indeed it works its easier than unloading the tune to get access with forscan or if not having foracan (many dealerships don’t even mention the fact or do it themselves) issues upon issues stack up. So mine resolved by resetting/relearning pcm/abs adaptations all together and well BMS being one of the common ones every 2-3 years if not done probably 1 year since it won’t charge properly

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[MuSwede]

Hi all! New member from Sweden here.

I drove an S550 V8/AT in the US for a while when I was visiting family in 2019. Loved the car and it was smooth as butter. When I came back to Sweden couldn’t be without that glorious V8, so I bought a used 2019 GT 10 speed in September of last year.

The somewhat sad part is that I have had problems with vibrations ever since I bought it. It’s been to Ford 3 times and so far the issue has not been resolved. It's going in to the dealer again within the next week or so, hopefully for the last time.

To make a long story short, I discovered the vibration a few weeks after I bought it. I can’t say the vibrations were huge, and vibrations usually just stem from some weight that’s come loose from the wheels I didn’t think of it as a big issue.

The car has since been tested with different sets of new tires and rims and all in scenarios the same type of vibration and vibration frequency reveals itself. There’s also a slight "rumble" noise in the car that coincides with the vibration frequency one feels. Ford has replaced a wheel bearing that they first thought was the problem, but it did not help. To provide a bit more context, Mustang (or V8 cars in general) aren’t super common here in Sweden, so many Ford dealers aren't very used to handling driveshaft related problems since most cars sold are FWD.

Given that this forum thread concerning vibrations in drivelines is 249 pages long and about 3700 posts it doesn't seem to be a completely unusual problem.



NVH Analysis

I'm pretty nerdy and started reading about different NVH analyzes (Noise, vibration, harshness) and calculating the different rotational frequencies in the car. I ended up buying an NVH app that’s backed up by research that goes all the way back to 1994. The founder is a professor (John D. Kelly) at Weber State University. He also has a Youtube channel that I can recommend where he posts all sorts of in-depth and nerdy videos about drivelines and more. https://www.youtube.com/user/WeberAuto. Some of you may have seen his videos.

Anywho, I bought the app (paid about a hundred US dollars for it) and it uses the gravitometer that is built into modern smartphones. Apparently, the sensitivity of gravitometers in modern smartphones is so good that it can replace many of the extremely expensive specialized equipment, although the app has its limitations in smartphone format. An example of something that is not yet available for the app are wireless or wired sensors that you can place on the outside of the car, but it may to be underway. This is to better pin-point where the vibrations originate from.

You start the app, enter the gearing for the gearbox in the car, wheels / tire sizes, gear ratio for the rear axle and then you go out and drive. You can then filter out the results as a PDF report, or dive deep and immerse yourself into all the data that's been collected. Since the S550's generally have different size front and rear tires the app knows (based on the frequency of rotation) whether wheel vibrations come from the front or rear wheels. It also detects engine vibrations (based on RPM) and drive shaft speed related vibrations (based on the gearing ratio in the car). When you have your results the app also provides suggestions on where to start to deal with the vibrations. There’s a big library of educational videos, pictures and guides, built into the app.

Below is an example of an analysis I did with the software on my own car. In this example I’d driven about 19 minutes on the freeway (Autobahn in Germany, of course, for legal reasons) and something that spins at the same speed as the driveshaft (and which gives 1 vibration per rotation, i.e. imbalance, 1st order vibration) is what gives the most vibrations, percentage wise.

It says transmission speeds 6 for unclear reasons, but in this particular case it does not matter because the vibrations are the same regardless of which gear is used. If you have vibrations that seem to stem from the engine, it is more important to get the gearing of the transmission right.

It’s also possible to break down the info into additional steps. For example, what percentage of the time the vibrations are detected as a percentage, see below.

In the example above, you can see that the vibrations from the part (driveshaft itself, most likely) that spins at the same rotational speed as the driveshaft are registered about 80-90% of the time at "normal" motorway speed.

Ford has been helpful so far, but they have not really managed to solve the problem yet. If they had used the app, maybe it'd all be done by now?

Hopefully it will be the last time I have to leave the car at the dealer’s. You all know how annoying it is to have a $50k+ butt massage machine that you can’t turn off when going on road trips on the freeway. I have probably collected several hours worth of data at this point for the car, and all the data indicate that the vibrations are connected to something that spins at the same speed as the driveshaft.

Wish me luck, because I'm starting to lose patience.

On a sidenote, this is basically a copy+paste (but in English instead of Swedish) of a similar post I did in a Swedish Mustang forum, but I thought I might share my experience in this forum as well.

Link to the app here: https://vibratesoftware.com/

A video that in a clear and educational way shows how to use the app:



I want to emphasize that I have no affiliation to the developer of that app by the way. I just happened to get frustrated enough to buy it, and the app happened to be pretty darn awesome.

Thanks

/H

 

[MuSwede]

Put the car up on the lift today and measured the runout on the driveshaft. It was about 0.4 mm in the rear, see video clip. I didn't see any balancing weights on the shaft.

It was about 0.4 mm closest to the front as well, by the gearbox. Perhaps a little bit less.

I also measured the runout on the pinion flange and it was 0.2 mm.

I have no idea if these are within specs, and a runout doesn't automatically mean imbalance. What's your take on it?

 

[Rapid Red]

Reading my service manual, planing for a bushing upgrade. Requires the transmission lower support to be removed. It was very specific about a couple of things.

1 Removing the drive shaft both ends should have witness marks on the shaft and mount points
2 The transmission lower support also requires the position to be marked, on the mount point of the frame/body.

Stressing failure to do so, drive train vibration may occur.

Watching some of the how 2 videos I have yet to see any reference. Mentioning the importance of the above. Be it lack of knowledge or promoting DIY upgrade, as simple .

I have had a drive shaft the was out of balance, was made for a car built. Chased a vibration around for a month, verifying & changing pinion angles and the whole bit.

After not finding a reason for the fault. Had another one made. problem solved, apparently the U joint fixture was off, bearing cups, the shaft ran true.

Food for thought

 

[888mustang]

Try turning clock position on drive shaft to rear pinion flange. That's how I fixed mine.Makes a huge difference.

 

[hlh1]

I had a 17GT that had the dreaded vibration and traded it on a 19GT that I now have. I have 8000 miles on this 19GT and it's starting to have a minor, noticeable, "rumble" that I can hear on quiet roads at 65+ mph. This is somewhat different from the 17GT that had the "vibration". Makes me think it might be a wheel bearing, or the drive shaft. I hate thinking about having to take it to the dealer.

 

[Rapid Red]

Try turning clock position on drive shaft to rear pinion flange. That's how I fixed mine.Makes a huge difference.

Good idea to start with, suggest putting witness marks on the pinion flange & drive shaft flange.

If vibration gets worse owner can return to the original position.

 

[MuSwede]

Hi all! New member from Sweden here.

I drove an S550 V8/AT in the US for a while when I was visiting family in 2019. Loved the car and it was smooth as butter. When I came back to Sweden couldn’t be without that glorious V8, so I bought a used 2019 GT 10 speed in September of last year.

The somewhat sad part is that I have had problems with vibrations ever since I bought it. It’s been to Ford 3 times and so far the issue has not been resolved. It's going in to the dealer again within the next week or so, hopefully for the last time.

To make a long story short, I discovered the vibration a few weeks after I bought it. I can’t say the vibrations were huge, and vibrations usually just stem from some weight that’s come loose from the wheels I didn’t think of it as a big issue.

The car has since been tested with different sets of new tires and rims and all in scenarios the same type of vibration and vibration frequency reveals itself. There’s also a slight "rumble" noise in the car that coincides with the vibration frequency one feels. Ford has replaced a wheel bearing that they first thought was the problem, but it did not help. To provide a bit more context, Mustang (or V8 cars in general) aren’t super common here in Sweden, so many Ford dealers aren't very used to handling driveshaft related problems since most cars sold are FWD.

Given that this forum thread concerning vibrations in drivelines is 249 pages long and about 3700 posts it doesn't seem to be a completely unusual problem.



NVH Analysis

I'm pretty nerdy and started reading about different NVH analyzes (Noise, vibration, harshness) and calculating the different rotational frequencies in the car. I ended up buying an NVH app that’s backed up by research that goes all the way back to 1994. The founder is a professor (John D. Kelly) at Weber State University. He also has a Youtube channel that I can recommend where he posts all sorts of in-depth and nerdy videos about drivelines and more. https://www.youtube.com/user/WeberAuto. Some of you may have seen his videos.

Anywho, I bought the app (paid about a hundred US dollars for it) and it uses the gravitometer that is built into modern smartphones. Apparently, the sensitivity of gravitometers in modern smartphones is so good that it can replace many of the extremely expensive specialized equipment, although the app has its limitations in smartphone format. An example of something that is not yet available for the app are wireless or wired sensors that you can place on the outside of the car, but it may to be underway. This is to better pin-point where the vibrations originate from.

You start the app, enter the gearing for the gearbox in the car, wheels / tire sizes, gear ratio for the rear axle and then you go out and drive. You can then filter out the results as a PDF report, or dive deep and immerse yourself into all the data that's been collected. Since the S550's generally have different size front and rear tires the app knows (based on the frequency of rotation) whether wheel vibrations come from the front or rear wheels. It also detects engine vibrations (based on RPM) and drive shaft speed related vibrations (based on the gearing ratio in the car). When you have your results the app also provides suggestions on where to start to deal with the vibrations. There’s a big library of educational videos, pictures and guides, built into the app.

Below is an example of an analysis I did with the software on my own car. In this example I’d driven about 19 minutes on the freeway (Autobahn in Germany, of course, for legal reasons) and something that spins at the same speed as the driveshaft (and which gives 1 vibration per rotation, i.e. imbalance, 1st order vibration) is what gives the most vibrations, percentage wise.

It says transmission speeds 6 for unclear reasons, but in this particular case it does not matter because the vibrations are the same regardless of which gear is used. If you have vibrations that seem to stem from the engine, it is more important to get the gearing of the transmission right.

It’s also possible to break down the info into additional steps. For example, what percentage of the time the vibrations are detected as a percentage, see below.

In the example above, you can see that the vibrations from the part (driveshaft itself, most likely) that spins at the same rotational speed as the driveshaft are registered about 80-90% of the time at "normal" motorway speed.

Ford has been helpful so far, but they have not really managed to solve the problem yet. If they had used the app, maybe it'd all be done by now?

Hopefully it will be the last time I have to leave the car at the dealer’s. You all know how annoying it is to have a $50k+ butt massage machine that you can’t turn off when going on road trips on the freeway. I have probably collected several hours worth of data at this point for the car, and all the data indicate that the vibrations are connected to something that spins at the same speed as the driveshaft.

Wish me luck, because I'm starting to lose patience.

On a sidenote, this is basically a copy+paste (but in English instead of Swedish) of a similar post I did in a Swedish Mustang forum, but I thought I might share my experience in this forum as well.

Link to the app here: https://vibratesoftware.com/

A video that in a clear and educational way shows how to use the app:



I want to emphasize that I have no affiliation to the developer of that app by the way. I just happened to get frustrated enough to buy it, and the app happened to be pretty darn awesome.

Thanks

/H

So, just had the car in at ford for hose clamp balancing.

Short story is they weren't able to do it. Nothing's fixed.

I'm gonna try another dealer.

 

[GTP]

My 2016 had a very slight vibration. Didn't bother me too much.
My 2019 was smoother and I never detected any vibration. Until a couple weeks ago.
I did a 3/4 pull on a freeway on-ramp. For about two seconds I thought the freeway surface caused vibration. And then I thought of the driveshaft.

It is possible for a single pull to cause the issue to begin?

 

[BLUDICE]

So, just had the car in at ford for hose clamp balancing.

Short story is they weren't able to do it. Nothing's fixed.

I'm gonna try another dealer.

Any update on the hose clamp balancing?

 

[MuSwede]

Any update on the hose clamp balancing?

The slightly longer short story is that they measured the driveshaft etc, in accordance with the Ford Service Manual, and found that everything was within spec. They drove the car (again and again) and couldn't pinpoint where the vibrations came from. They therefore did not try even the hose clamp method. Since there's only licenced dealers in Sweden (not "real" Ford dealers per say) they were unwilling to do any work on the car that they were unsure that they would get paid for. The particular dealer I went to with my problem had very little (or any) experience dealing with vibrating drivelines. I should have understood this earlier and just gone with another one, but Captain Hindsight arrives late sometimes (for those of you who get the South Park reference).

I've managed to get hold of another dealer that (I think?) is the one that sells the highest number of Mustangs per year in Sweden. It's about a 2 h drive away from here, but I figure it's worth it if they can fix it. I rang them up and the technician I talked to on the phone had fixed around 20-30 vibrating Mustangs. In 95% of the cases a simple hose clamp system balance method had fixed the problem. In the one's that he couldn't fix they exchanged the entire rear "axle lump" with the diff, rear axle etc etc, since that had been the culprit in 4-5 cases and (surprisingly) not the driveshaft, at least on the newer cars.

He'd gladly take a look at the car and give it a try. I've booked a new appointment with him instead. They were very busy before summer vacations and the first available appointment was on june 29. I'll provide a new update after that.

 

[BLUDICE]

The slightly longer short story is that they measured the driveshaft etc, in accordance with the Ford Service Manual, and found that everything was within spec. They drove the car (again and again) and couldn't pinpoint where the vibrations came from. They therefore did not try even the hose clamp method. Since there's only licenced dealers in Sweden (not "real" Ford dealers per say) they were unwilling to do any work on the car that they were unsure that they would get paid for. The particular dealer I went to with my problem had very little (or any) experience dealing with vibrating drivelines. I should have understood this earlier and just gone with another one, but Captain Hindsight arrives late sometimes (for those of you who get the South Park reference).

I've managed to get hold of another dealer that (I think?) is the one that sells the highest number of Mustangs per year in Sweden. It's about a 2 h drive away from here, but I figure it's worth it if they can fix it. I rang them up and the technician I talked to on the phone had fixed around 20-30 vibrating Mustangs. In 95% of the cases a simple hose clamp system balance method had fixed the problem. In the one's that he couldn't fix they exchanged the entire rear "axle lump" with the diff, rear axle etc etc, since that had been the culprit in 4-5 cases and (surprisingly) not the driveshaft, at least on the newer cars.

He'd gladly take a look at the car and give it a try. I've booked a new appointment with him instead. They were very busy before summer vacations and the first available appointment was on june 29. I'll provide a new update after that.

Thanks

 

[GTP]

My 2016 had a very slight vibration. Didn't bother me too much.
My 2019 was smoother and I never detected any vibration. Until a couple weeks ago.
I did a 3/4 pull on a freeway on-ramp. For about two seconds I thought the freeway surface caused vibration. And then I thought of the driveshaft.

It is possible for a single pull to cause the issue to begin?

I answered my own question.
Put my track day wheels on Sunday, and now the car is perfectly smooth again.
Guess I'll have to take the daily wheels to a tire shop for further investigation.

 

[qwk93ta]

i owned a 15 GT that had this vibration and i sold it. thinking ford had fixed this issue i bought an 18 GT with 3k miles. it’s been back to ford several times for this vibration and the 2k rattle….does says the rattle is normal and they can’t figure out the vibration. with the crazy used car pricing i decided to sell the car to a local ford dealer. i’m done buying mustang for a while.

 

[BLUDICE]

i owned a 15 GT that had this vibration and i sold it. thinking ford had fixed this issue i bought an 18 GT with 3k miles. it’s been back to ford several times for this vibration and the 2k rattle….does says the rattle is normal and they can’t figure out the vibration. with the crazy used car pricing i decided to sell the car to a local ford dealer. i’m done buying mustang for a while.

FYI my ‘19 Ecoboost did not have vibration.

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