Power Brake Conversion

[BillyRay59]

I searched the Forum for a Manual Brake to Power Brake conversion but didn't find anything except for a Hydroboost conversion.

I just want to convert my manual brakes to power.  I know I have to change the pedal and add a booster.

Is that it?  Master Cylinder/Rod? Any brake Lines? Thanks in advance for any help!!

[Gary Lewis]

I don't think we have anything about converting to power brakes.  The vast majority of the trucks came with power brakes, so it is rare anyone needs to convert.

But according to our page on brakes (Documentation/Driveline/Brakes) it looks like your master cylinder is probably E0TZ 2140-C and you need to go to D7TZ 2140-C.  And the booster will be E0TZ 2005-A.

As for the lines, I don't know.  But I'd bet that you won't have to change them.  Surely the fitting sizes are the same and there's usually plenty of extra line in the coil so you can move the master cylinder forward.

[ArdWrknTrk]

Aren't there caliper/spindle mounting differences as well?


I know nothing about the lighter duty brake systems, but somehow I recall Dave having an issue with his Flareside.

I'm going to tag him anyway.

[Gary Lewis]

Yes, there are differences at the caliper, but I assumed BillyRay is going to keep the existing calipers and just add boost.  However, if he is wanting to change them then that's a whole different kettle of fish.

[ArdWrknTrk]

Oh. I thought by changing the master cylinder bore you would need to swap out the calipers to have an effective ratio.

Thanks for enlightening me!  

[Gary Lewis]

Didn't someone put an F450 master on an F250 w/o changing the calipers or rear brakes?  

[ArdWrknTrk]

8,500# and up all have the same bore master cylinder.
There's no difference there.

Just because you swapped a vacuum booster for a hydraulic booster doesn't change the master/slave ratio.

Edit:
But looking at your chart above, it seems 100/150 both with and without booster use a 1" bore master cylinder.
And this is why I said I'd tag the guy who I remember having to deal with changing from no assist to power brakes.
(I still want to hear what Dave has to say)

[FuzzFace2]

Dave is in the house

Ok I did the swap from non-power to power on my 81 F100 using parts from a 81 F100.
Before I did the swap and as Jim pointed out the I found the masters had the same bore dia.

I also found in the search that the rear wheel cyl were the same dia. but the drum & shoe sizes were different, cant remember what one was the larger, maybe the non-power?

I also found in the search that the calipers had the same piston dia.
Also as pointed out the calipers, pads, rotors, spindles, beams will not interchange.

So all I did was take the power brake pedal assy, booster & master from the power brake truck and bolted it into my non-power brake truck.

Hope this answers some questions for the 100/150 trucks
Dave ----

[ArdWrknTrk]

Thanks for weighing in, Dave!  

I hope it clears things up for Billy Ray.

[FuzzFace2]

Yea if he has an 81 like in his sig then he could do what I did, get a power peddle assy., booster & master.

I did have to replace the booster & master as they were bad and think that is why the parts truck rolled on its roof.
Dave ----

[Gary Lewis]

Yes, thanks Dave.  

[BillyRay59]

Thanks for the info everyone!  I knew I had to change the pedal, I found that here:

http://www.garysgaragemahal.com/#nabble-td65450i20|a65556

I read on another site that all I had to do was change the booster, but they didn't mention the MC.  My truck only has 52k miles, nothing is really worn out, so I only want to change what I have to.

I wanted to keep it all original, but I'm getting too old to stand on the brakes!

Thanks again!

[BillyRay59]

Also, I am not swapping out the calipers/etc.  The rear drums are bigger on the manual brakes, so that's a good thing, I think.

[BillyRay59]

ArdWrknTrk wrote

But looking at your chart above, it seems 100/150 both with and without booster use a 1" bore master cylinder.

So, I'm wondering what the difference is then between without booster (E0TZ 2140-C) and with booster (D7TZ 2140-C) if the bore is the same.

[ArdWrknTrk]

It says right in the chart that both have a diameter of 1"



Though the non-power master probably has a mount for the firewall and the power master has a different C-C, or other mount configuration where it attaches to the booster.

I definitely know that the larger bore 250/350/450 master cylinder won't fit a 100/150 booster.

[BillyRay59]

Thanks Jim! I was hoping to reuse my manual MC, but to be safe, I'll get the one for PB.

ArdWrknTrk wrote

It says right in the chart that both have a diameter of 1"

Though the non-power master probably has a mount for the firewall and the power master has a different C-C, or other mount configuration where it attaches to the booster.

I definitely know that the larger bore 250/350/450 master cylinder won't fit a 100/150 booster.

[FuzzFace2]

I am going to go out on a limb here and say the difference between the power / non-power masters is the rod.
The power master dose not have the rod on it as it is in the booster.

The non-power would have the rod in it that goes through the firewall to the peddle.


Now can you pull the rod out of the non-power master and use it is the $98 question?
I swapped the whole unit as they were working (so I thought) on the parts truck so they should work on my truck without any issues.
Dave ----

[BillyRay59]

FuzzFace2 wrote

Now can you pull the rod out of the non-power master and use it is the $98 question?
I swapped the whole unit as they were working (so I thought) on the parts truck so they should work on my truck without any issues.
Dave ----

I'm gonna do the same thing you did Dave just to be safe.

[FuzzFace2]

I am pretty sure the difference between them is the rod and I dont know if they can be swapped but would say no.

Because both the master, peddle would sink with foot on it, and booster, vacuum leak when peddle was pushed also, I replaced them both at the same time.
Think I went through Auto zone as they were just down the road and I wanted it ASAP as I wanted to take the truck to the company car / truck show.

At first the only thing I did not like was the brake paddle was lower that I like it.
No it would not pump up so no air in lines and the rear shoes were adjusted right.
I did try and adjust the rod between the master and booster but that really did not do anything.
You have to be careful if you adjust this rod as it can apply the brakes even with the paddle up all the way.

I have gotten use to it and dont even think about it now.
I dont know if the peddle was low like this in the parts truck as I never drove it, no motor, doors and roof was caved in from a roll over.

The truck gave up a lot to get my truck rebuilt the way it is today.
Dave ----