Shaking at high speed - is this normal?

[satchamo]

so my 21 screw STX with a 5.0 has some pretty annoying vibration at and around 80 mph. My passenger seats shakes pretty badly and anything in that seat shakes a lot. Like a simple McDonald’s bag which makes a bunch of noise. I have done nothing to modify this truck - completely stick with 1600 miles on the clock.

so I had my truck into the dealer a week ago over this issue and they test drove it and identified it as “flat spot” on a tire so they replaced a tire and said it fixed it… we’ll it didn’t.

could some of you other owners watch this video and tell me if you can discern the vibration I’m referring to?If you crank up the volume you will hear the bags shaking. I only ever drive this speed on interstate before anyone asks why I need to drive 80….

is this normal or should I take it back in? I already left it with them for 5 days to not get a fix…

Sponsored

 

[rado]

While I do not have my truck yet, I can be pretty sure that that's not normal. You can actually see the seat shaking in the video, suggesting its a pretty big vibration. Is it completely speed dependent or does it do it at all speeds? If I had to guess, I'd say that you probably have a tire or two out of balance. I'd take the truck to a shop that has a Hunter Road Force Elite Balancer (https://www.hunter.com/find-equipment/). I've found that they balance the tires much better than other equipment as they put an actual load on the tire during testing. Every time i've added larger M/T's to a truck I'd have to get them taken to a road force to get the vibrations out of the drive train.

 

[Jerry Can]

That vibration is definitely not normal. My truck is perfectly smooth at 80mph. Did the dealership check wheel balance and alignment?

 

[BMWtoF150]

My 17 f150 had the same kind of vibration @ 75 +MPH. I had all the tire balanced at Discount tire and it corrected most of the problem Part of the problem was the Good Year tires that came on the truck. They just rode bad. Once I put Michelins on It was very smooth. My 21 has Parelli tires and has been very smooth for the 9700 miles I have driven it.

 

[satchamo]

That vibration is definitely not normal. My truck is perfectly smooth at 80mph. Did the dealership check wheel balance and alignment?

Let me take a pic of the service ticket and it will indicate what they did

 

[Predator]

Had a vibration problem in my 2018 5.0 the rear axle gears were bad dealership changed them and vibration was gone

 

[satchamo]

So here is what they gave me on the tires

seems like way more road force on both front and rear on right side but I literally have no idea what this means haha

 

[KartRacer25]

Should definitely be rock solid up to 106 mph all day long.
Saw a few post on drive line issue and other vibration sources. Something about angle of drive shaft or something. Plus some earlier recall issues. Do some searching on virations here and other F150 forum under 2021's
Hope you can sort it out.

 

[mtbmj]

2021 F150 SC Lariat 502A pkg 3.5 EB having NVH most noticeable 50mph thru 60 but at lower mph and higher mph to a lesser extent. Selling dealer hooked up a sensor system and did a trans / torque converter test as recommended by Ford Corp. no resolution. I checked drive shaft visually and noted RPM vs gear selection to no avail. Any help here? 20" w Pirelli had winter setup, same issues. Stock suspension no mods on anything.

 

[Jayet96]

2022 F150 XLT FX4 with 2300 miles. I’m having same issues. Installed level kit and 275/70r18 Cooper Discoverer AT3 after I took delivery. I’ve had the tires balanced 2 times, road force balanced yesterday and still shakes. I have an appt with selling dealer on Friday. At this point I’m thinking it has to be an issue with the truck.

 

[fordhouston]

have them rotate the tires and then see the after results?

 

[Jayet96]

have them rotate the tires and then see the after results?

Thanks for the reply. They were rotated with the second rebalance.

Sponsored