No - turn off the engine and then pump the brake pedal to deplete the vacuum in the booster.


And to add on to all my previous comments (I hit the max size on my previous post)...

I don't disagree that adjusting the booster output rod can help. There is always a possibility it was set wrong, or that you got one at the far end of the tolerance. I disagree that the average owner should be doing this in his garage.

And one last comment - for average stopping, you should never use the entire brake pedal travel... generally only 40-60% of the total travel, if that. If you have to "double pump" because your brake pedal is bottoming out on the floor, then you have other issues that need to be fixed.

 

[B][mkosu04/B], My truck, Brand new, had crappy brakes. The dealer had bled the hole system, (changing the brake fuid, that had no moisture in it) still did not help the pedal at all. The pads were not worn out, at 6000 miles and at 10,000 miles, or 15,000 miles. Once i adjusted this rod, my stopping pressures on each axle inproved, where they are supposed to be. (Checked before and after on the HEKA Machine). I have personally checked each wheel caliper for dragging brakes, Which i have found none. I also have a lazer thermometer that i check each wheel for excessive heat, which i found none. This rod adjustment has made a difference in my brakeing, and i will continue to reccommend this. Now, why would you want to have to push your brake pedal and release it in order to replentish the fluid so you can stop in an emergency situation???? It just does not make any sence to me. Especially when i drive other Ford products such as the Tauras, Mustang, and others that stop perfectly without pumping the brakes. If this is the way to drive this truck, (Pumping the brakes to stop), Then Ford needs to retrain all of it's customers....

 

I feel that the average DIY can do this adjustment if they only turn it out one turn and check each wheel for brake drag before and after. This is why i reccommend marking the rod for a reference point, so you either can return it back to the original position. If you can change the oil or a tire, you can do this adjustment. I feel that these rods are not adjusted right from the factory, or the supplier.

 

you misunderstood my description of the brake replenish process.

Like I said at the end of my post - you should never have to double pump. If you bottom out your brake pedal on the floor and are not getting a 4-wheel lock (or ABS) then there are issues with the brake system.

And again, I don't dispute the fix. I dispute the idea that the average owner should do it themselves.

 

you are underestimating the complexity of the system - just because the brakes are not dragging when you drive around the block after the change does not mean that you are not going to experience a problem some day.

One day you may be driving through mountains or some other situation that results in the extended use of your brakes. Due to the higher brake temperatures you see more of a dynamic response in the brake system (brake fluid heats and expands while you have the brakes applied). This causes the brake system to supercharge and you can lock all 4 wheels. Letting go of the brake pedal DOES NOT release the pressure because you turned out the output rod adjustment nut. Now you are sitting on the side of the road waiting for your brakes to cool down so you can drive again.

Don't think this is possible - go back and read RMS8's comments. At one point he describes this EXACT EXPERIENCE with his mustang. He said he was close enough that he could "limp home". What if you are on vacation and driving through the mountains when it happens??? That would sure ruin a vacation pretty quick.

I don't mean this as a personal attack. I'm trying to show all the risk involved with this modification. I know what I am talking about. We do extensive testing on these brake systems... we have even set output rods ahead (like you talk about doing here) on some vehicles and proved that you can trap pressure.

So... do what you want to your truck... hopefully it works fine.
but if you find yourself sitting on the side of the road, just don't say you weren't warned

 

Fair comment.

However....

How do you account for the several "just anybody" who have successfully performed this modification?

I, most certainly, fall under the same "just anybody" catagory you label here, and I'll attempt this modification this weekend.

I'll let you - and others - know how the average "just anybody" does.

 

I just did this on my truck over the weekend. Best thing I have done yet for the braking

 

*bump*

mkosu04... ?

 

Question for you guys.

My pedal usually feels soft the majority of the time. If need be it will stop fast just seems to be alot of pedal travel and its been this way since the truck was new. The question is that some times when I've had it in to get work done (not brake related) the pedal will be rock hard like it should be when I get the truck back. The last time was when I took it to a shop and had the alignment fixed and the pedal was solid for a week and now it is getting softer again. What causes this?

Thanks

 

A couple of things can cause a soft pedal. First, check your brake fluid resavoir for low fluid. Top off if necessary. If low, check for leaks, and worn bake pads. If all of that is ok, the brake system might need bled. Check all wheels for brake function. You will have to jack up the truck, and spin the wheel and have someone apply and release the brakes. If all of that is fine, then i reccommend the brake rod adjustment that is explained in this thread.

 

The rants of someone who apparently has a bit of the "bunnched-panties-syndrome”



LOL, “…very advanced mod…” OYE-efen-VEY!



Let make this very clear (as I did in the FIRST post), you see my dealership made the adjustment. Pretty simple to grasp isn’t it. As far as your informative “NEWSFLASH” informing us that the MC in my F150 is different that the MC I INSTALLED IN MY RACECAR, well all I can say is thanks. It was masterfully written.




WOW. I can see you’re mature BEYOND your paltry years reveal. “If I knew what I was doing” LMFAO. Seriously, how many vehicles have you restored from the ground up? Get over yourself junior.




Yet another verbally ignorant bucket of vomit coming from your keyboard.



LMFAO-again…..seriously, you’re kill’n me….


What exactly is a “degreed” ME? By the very nature of being a Mechanical Engineer, you are degreed, be it a Bachelors, Graduate or PhD. Go figure. BTW, I have a Masters in EE and more years in experience when it comes to building engines/cars than you’ve been blessed to be alive.

 

Just curious how it went for ya Grubrunner?

About the ONLY thing that junior said that was of any use was the fact that if the rod is adjusted too far, then the brakes could lock up on you after a while, but.....this was ALREADY covered towards the beginning of this thread.

 

It is full of fluid, never has leaked. Breaks have been bled and there is no brake malfunction at the wheels that I can find. The soft pedal just comes and goes. Just about every time the truck goes into the shop it comes out with the pedal being rock solid for some reason?

 

Well I did the mod and I must say that there is a noticable difference in brake pedal feel. I only turned it probably a half of a turn. No more spongy brakes. I had the dogs with me so I couldn't use them like I wanted to but I did notice a difference. What an easy mod.

 

Never got a chance but I'm hoping the weekend after this coming one.

Will keep ya'll updated.