After many searches and skimming thru a lot of posts on here I finally found what I needed to adjust my soft break pedal on my 2001 F150 4X4. it was a little tough to find the info so here's what I did with pictures and discriptions.

1. location of the 14mm nuts that hold the MC to the booster
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2. Tools needed, 7mm wrench, 3/8 ratchet, 14mm deep socket and 2 inch extension, pliers.
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3. Location of the bolts, no need to disconnect lines or wires. once the nuts are removed the MC will move out of the way enough so you're able to get to the adjustment.
[IMG][/IMG]
4. adjust the 7mm bolt counter clockwise while holding the booster shaft with pliers. I did mine a half a turn at a time, test driving between adjustments.
[IMG][/IMG]

5. end results - Ended up at 1 1/2 turns and it felt real good. No breaks dragging and the pedal was back to where it should have been. I did raise the front and back of the truck once I was complete and happy with the adjustments, spun the wheels to ensure there was no brake drag. (highly recommend this)

Adjusments very by truck, from what I have found during my searches on this forum it can be anywhere from 3/4 turns to 2 full turns. This is why you need to go in small incermints 1/4 to 1/2 at a time and make sure the adjustments are where you're happy with them and the breaks are not dragging.
My break pads, roters, calipers were all new within the last 2 months also.

note: I have read in these forums that there may be some pressure (vaccum) on the MC when you pull it, I did not have that issues but you may need to pump the break a little while it's not running to release the pressure. In all the MC's that I have changed over the years I never ran into this issue but one never knows.

Good luck and hope these pictures help.

This is information on what worked for me, may not be for everyone and you do these adjustment at your own risk.

 

great post. I always wondered how to remove that initial 'squishyness' out of the brake pedal.

going to do this later today and report back later.

 

Thanks for a very nice writeup with the pictures. I have copied it over and indexed it in the Articles and How To. Your contribution to the site is greatly appreciated!

 

Thanks, glad I could contribute. I just spent a ton of time reading many posts to get all this info togeather and thought if it was all there in one spot with the pics it may help someone else out on the time consuming search.

 

I will post once again on this new thread to say this is a very bad idea. Doing this adjustment could have very bad consequences.

You checked for dragging brakes while sitting in your garage. This is the easiest time to avoid dragging brakes. There are dynamic situations in driving that are much more sever, and much more likely to cause dragging brakes. The most likely example is if you are driving down a mountain and using your brakes rather heavily. The thermal expansion of the brake fluid in the wheel calipers will cause the master cylinder pistons to return under pressure (we call this "super-charging" the master cylinder). This pressurizes the seals and since you adjusted your booster output rod this extra pressure cannot escape.

The other likely possible problem (on newer trucks, not on your 2001) is if the traction control pumps fluid from the MC and then you step on the brakes. This results in extra fluid again and the MC is super-charged.

Either one of these situations could cause you to be sitting on the side of the road with all 4 brakes locked.

TRUST ME ON THIS - I design, build, and test master cylinders for a living. We have performed tests to show this is possible and have even duplicated it in real life.

Still don't trust me? Look at post #2 in this thread
https://www.f150online.com/forums/20...-symptoms.html

There is another risk for newer vehicles with Traction Control - the traction control module needs to pull brake fluid from the master cylinder to apply the brakes. If you adjust your output rod on the booster you are effectively closing the compensation ports in the master cylinder. This chokes off the area for the brake fluid to flow through. At cold temperature (like in the winter, when traction control is needed) the brake fluid becomes very thick. Performing this modification could cause your traction control to fail.

Please take all these risks into consideration before adjusting your booster output rod. If you read all this and still do it, don't say I didn't warn you!