On my 2007 f350 when I hit my brakes it pulsates... so I put new rotors and brakes up front.. the pins are good and the calibers are good... put it all back together and still the same thing... the slower you go the slower the pulsating gets... and I can actually feel the pedal move in and out when it does it... I'm lost

 

Either your front rotors you installed are still warped, or the back brakes are causing it. Thats where I would start.

 

Try driving (very slow) and GENTLY apply the E-Brake ..
can you feel the truck pulsate ?

No .. apply the E Brake just a little more .. still no ..
maintain the E-Brake pressure until the truck stops.

If you felt the pulsation, you've isolated it to the rear brakes.
If you didn't, I'd re-address the Front Brakes.

Also .. (if) you've diagnosed the pulsation to the Rear Brakes, while you have everything apart, ensure the E-Brake cable is working properly and lube all of it's contact points.

 

4 brakes... only 1 to cause a problem..

as already stated.

 

Since the e-brake uses the drum inside of the hat, this method will not tell you if a rear rotor is causing the issue.

 

Stuart beat me to it, the parking and service brakes use separate parts of the rotor. That technique would only work if the E-brake and service brake were the same component, which they are not on a Super Duty.

To the OP: What made you so sure it was the front?

 

From my experience, you can feel it in the steering wheel if it's the front, you will feel it more in your seat if it's the rear. If the pedal is pulsating, I would think it's an abs issue.

 

I think that is true for vibration issues but not applicable to brake issues. My experience is that any rotor issue, front or rear, will be felt in the pedal.

 

You are correct, you can feel it in the pedal, but I've never had the pedal pulsate in and out like the op described.

 

Did you replace your brake hoses? If not they are 10 years old and due. They could be collapsing. They are cheap and easy to replace. Worth ruling them out.

 

HOT spots .. front or rear.. will make pedal go up or down...
sometimes heat cracks will also..

but BOTH will be visible with wheel removal...
and YES it could be on inboard or outboard on one side..

 

I (assumed) your Rear Brakes were Disk .. my bad !!

 

The rear brakes are disc brakes, but the parking/e-brake is a drum brake that is integrated into the disc.

 

Tires.

Ten characters.

 

Aren't those hydroboost systems? I can't remember what my 06' 350 had and I may be confusing it with my 02' GMC 2500 system... But it would do the same thing on occasion.