Hi All
I have a 2019 f150 4x4 with 55000 miles and my truck started heavily vibrating when I brake at freeway speeds, it is completely normal at slower speeds. I took the truck to a mechanic thinking it was my brakes and got the front rotors and pads replaced. When I was picking up the vehicle, the mechanic said there is some play in my lower control arm bushings and that also could’ve possibly been the problem.

The problem didn’t go away and I took the truck to a ford dealership and they said the LCAs are fine and blamed the mechanic probably didn’t do a good job on the brakes - I mean it’s pretty straightforward to replace rotors and pads or the new rotors were defective. I then had my mechanic replace the rotors again just to prove to the dealership it wasn’t the brakes and after this, the problem still exists. I do have extended warranty that should cover LCAs, could that be why the dealership doesn’t agree with Me? The dealership are now saying we should resurface the new rotors and go from there. I’m clueless how to proceed now as it’s definitely not the brakes.

 

How do you know it's "definitely" not the brakes, when the people who work on F150s all day every day think it is? When you have a problem that could be a warranty issue, go to the dealership first. They do brake jobs. Even if you didn't want them to actually do the brake work, they could have identified the root cause of your problem before you muddied the water with someone else's work.

The dealership gets paid by Ford to do warranty work, so they should be happy to repair a problem that's covered by a Ford ESP. Your least expensive path at this point is probably be to go to another dealership, describe the problem to them, and let them troubleshoot. They may decide it is the LCAs or find another problem that's been missed. Good luck.

FYI, I recently shopped a brake job with my Ford dealer and with an independent shop I've been satisfied with in the past. The dealer was about 25% cheaper, and there's nothing wrong with MC rotors or pads.

 

I seriously doubt that lower control arm bushings are causing your pulsation while braking. Diagnosing whether or not it is a brake issue is simple with a runout gauge. I suspect in this order: REAR brake rotors are warped (yes rear rotors also can cause pulsation), a front hub is bent which transfers that runout to the rotor (you can usually see this by simply rotating the wheel), or defective front brake rotors. No it is NOT caused by that silly little "build up" on the rotor nonsense that somehow gained traction on the internet.
Again, a run-out gauge is the most important tool here.

 

I’m saying it’s not the rotors and pads as the dealership are claiming because I’ve replaced them twice in the span of 2 weeks. To you point on “muddying” the water - I took it to the mechanic I’ve been going for years since brake wear isn’t covered under warranty. The dealership checked the other suspension components, rear brakes and said everything looks good. They’re still insisting they need to resurface new rotors to start with this.

 

just because they are new doesn't mean they are good. I have seen more than my fair share of rotors with excessive run out right out of the box

agree on the rotor resurfacing

 

Although I’d bet rotors need turned, it could be a sticky caliber

 

Some experience to pass on.
When braking and pulsing begin; if a Disc is warped or out of True over it surface diameter for any reason, when the disc irregularity passes through the Caliper Pads, the Pads try to do their frictional job and slow the disc enough to begin side to side steering effects as well as forward speed changes (pulsing).
The Disc can even be temperature sensitive to the distortion and heat build-up per time.
.
Sometimes over tightening the Lug nuts can distort the Disc.
Guide pins that need Lubing or are frozen can be source or add to the problem.
Front end wear can be a secondary add once it begins.
I have experience on two greatly different year F 150 for the same issues.
Best to avoid background "think off dismisses" and go after the cause by checking for all the possible causes because there may be more than one cause.
Good luck.

 

aa stuck caliper will warp the rotors and make them bright red. when they cool brakes will be normal. If this happens at night. stop and look at the rotors. they will probably light up the night.