|So you want Real
in your Jeep?
Submitted by Keith Kreutzer
(His rig is pictured above)
Please send your questions/comments to: firstname.lastname@example.org
It's simple, Use a booster from a'94 GM pickup, I'm not certain what else they fit onto
or what the as new Part Number is but that's what the subject booster is off of. I believe
that all the late model GM Truck boosters that have the "four stud pattern" on
the back are the same.
Stuff you might have to buy:
- Power Brake booster off of a mid '90's GM 1/2 ton pickup with four studs on the back.
- Good quality 3/8 female rod end.
- Real 3/8 24 "jam Nut"
- 3/8 24 Threading Die.
The modification goes like this:
I got my booster from the local Wrecking yard for $50 with a Master Cylinder. I didn't
use the master cylinder but I could if I had to. Take your master cylinder loose from the
booster but don't loosen the brake lines, carefully move it aside so you can remove your
old booster. Set the booster aside for future measurements.
On to your new booster:
The Actuation rod on the back of the new booster is too long so cut it off just about
an inch or so past the eye that pins it to the pedal, this may seem too long but wait I'll
tell you why next, the eye is HARD so don't get too close to it or you'll ruin lots of
hack saw blades. Find a 3/8 24 die and run it down the shaft as far as is possible. gently
hold the rod with Vise grips while cutting the threads. When you think you've gone as far
as you can put the vise grips on the other end of the rod ( out at the end you cut off )
and keep making threads, it's good to use a die that has a hex type body as opposed to a
round body so you can use a socket wrench to thread the shaft down deeper than you could
with a die handle. Run the die off the threads, but just before you reach the end that you
smashed with the vise grip, cut the end off, by doing this I found that you can use soft
jawed pliers to hold the shaft as you run the die off the rest of the way. Now test fit
the 3/8 24 female rod end to get the length of the actuating rod the same as the Jeep
booster, cut off a little at a time, file it down, get it right as you don't have too much
room for error. once you have it right screw on the 3/8 24 jam nut, it's important to use
a "jam nut" as they are thinner than regular nuts and you'll need the space.
Lock it all down with lock tight and you're done with this part.
Next you'll need to open up the holes on the factory booster mount gismo,
just about .100" or .050" per side. The stud pattern is the same
up and down but the bolts are bigger ( save the nuts from the wrecking yard
). Now loosen the booster bracket a little bit from the fire wall
squeeze the brackets together ( about a 1/4" total ) and slip in your
new booster Tighten the booster first then the bracket to the fire wall, put
the pin with the aggravating little clip back in and test for binding ( it
shouldn't it's a really loose mechanism anyway ) put on your master cylinder
and off you go, and you didn't even have to bleed the brakes. Did I forget
to talk about the vacuum line? Ahh you knew about that !! Be careful now you
should have real power brakes !!
I had no clearance problems with the hood, my booster assembly is raised about 3/4 to
get a little more leverage and the new bigger booster still clears. It's amazing the
difference. With 35 inch tall tires I feel like I'm in a Porsche ( when I'm on the brakes
going straight )
While using my brakes in this arrangement I found that they where just
too touchy. If I wasn't careful I found could easily lock up all four
Swampers at 50 MPH, not a desirable thing! At least not that easy. So since
then I've omitted the Rod End in favor of a handmade piece that I could make
shorter that the rod end, allowing for a little bit more freeplay in the
pedal. I simply took a good piece of steel 4140 about a 1/2 inch wide an
inch tall and about 1 1/4 long I drilled into it the long way I tapped it
3/8 -24 and drilled it for an 8-32 set screw. Then I drilled a 3/8 hole
across and replaced the Rod End with my piece o' metal lock tighted and set
screwed it all together. Now the brakes are a bit easier to manage and I
still have enough power to lock up the tires at high speeds It's just way
easier to modulate them so I won't now.