of breaking D44 front U-joints or bending the front axle tube after 6 foot air jumps? Well, here
is the solution. Install a D60 front.
me say up front that is will be a pretty spendy adventure and
for 99% of us,
at least some machine shop work will be needed.
lets get to it!!!!!!
you need to locate a 78/79 RC D60 front. They are getting harder
and harder to find. I paid
$600.00 for mine, but I doubt you will get it that
cheap. In some parts of the country they go for $1200.00+. You can
not "easily" use an
86-97, D60 front with C-bush mounts. In 1980, Ford changed
the front of frame on all F-series (widened), they also moved the
differential outboard, not leaving enough space for the C-bush mount on
the drivers side.
you will need to decide if you are going to hack up your stock
axle or look for a donor D44 front for the C-bushing mounts. This
was an easy decision for me as I had one with a bent front tube
from doing 30+ jumps and NO suspension lift :-)
when looking for donor front axle, make sure you get one with
same size tube as your bronco
axle, some F100's had light duty D44 front, which
will bolt into any C-bushing front end, but the tube is smaller
and the mounts are lighter duty).
sure truck is level, side to side and front to back. Measure the
pinion angle of your currently installed diff. Now measure the
angle of both your radius arms (hopefully they are the same or
at least close). Then, take your donor axle, gut it and find a
machine shop. Both C-bush mounts need to have the tube cut off
of each side. Then each mount must be bored out to a D60 front
axle tube size, which is a hair over 3". After boring,
mount is cut in half. Place each half against D60 front and
install D60 front in suspension with springs, leaving C-bush cap
bolts slightly loose. Drivers side mount just about fits and
should look like this after final welding. (See Figures 1,
and 2). Passenger side mount will look like this when done.
Also note massive 1410 axle U-joint :-) (see figure 3).
front shocks off at this point if you have quads. Make sure
truck is level again and measure radius arm angles. They should
be the same as before and if not figure out why. You may have
one spring longer than the other, lower spring mount may be bent
on one side (obviously, this should have shown itself on
previous measurements), or one C-bush mount may be binding
causing one spring to compress slightly. Now rotate axle
until pinion is at the angle that you initially measured. Now is
the time to decide if you want to rotate pinion to something
other than stock angle. More castor means rotating pinion
downward, but that also means a worse pinion angle. You can
adjust castor either way later on up to 7 degrees with bushings,
so it is usually best to set pinion angle at stock location Tack
weld in several spots and disassemble front suspension. Check to
make sure C-bush mounts are rotated the same angle in relation
to each other. Again they should be fairly close. If not, you
may have something wrong in the front suspension.
up the mounts all the way around on ends
and between each half of
each mount where they were cut in half. Have a PRO do this
unless you weld for a living (it's not worth your life for
$100.00 of welding!!!!!!!!!!!!!).
After welding install axle and bolt up passenger tie rod end.
Adjust drivers tie rod end until you can reach drivers side
knuckle. It will take quite a bit of "unscrewing" to
get it to reach.
getting toe more or less aligned, attempt to install front
shocks. Fairly heavy grinding of shock brackets and/or forward
part of C-bush cap may have to be done to keep tie rod end from
hitting these mounts. If you have thinner tires, the limit of
steering may be tie rod end hitting these shock brackets and/or
front C-bush metal cap. Adjust steering stops (might need to
make new one's from 1/2 inch bolts) until tie rods do not hit
anything at full lock. A substantial limit in steering may be
required with really wide tires. Luckily, a D44HD 8 lug or D60
front is wider (over stock D44 front axle) by a little over an
inch, this helps with radius arm rubbing.
also made custom adj. drag link (See Figure 4)
using a tie rod end setup (have this PROFESSIONALLY welded if
you do it!!!!!!!!!) and used a Superlift adjustable track bar.
Front drive shaft will need to be shortened and U-joint at
pinion changed to a 1330 joint if you have a 78 bronc (79's had
than that, it is pretty much a bolt in. Track bar may hit tie rods, front diff cover
and/or drag link at full suspension "stuff" of drivers
front tire if you have little or no lift. When you're done you
can hammer it through mud holes like this and your front end
won't even whimper :-).
for Converting to F250/F350 Leaf-Sprung Axle
alternative to converting a Bronco to a D60 coil spring setup
would be to use a D60 leaf spring setup such as the type used in
the F-250 and F-350 leaf spring axles. Unfortunately, this type
of conversion is much easier said than done. The F250/350 had a
different frame than F150/Bronco. The Power Steering box mounts
inside the frame on the F250/350 chassis vs. outside the frame
on F150/Bronco chassis. A minimum of 8" of lift would be
needed if you use a 1/2 ton PS box/pitman arm and leaf spring
suspension. The problem is the pitman arm sits directly under
frame, right where leaf sits. When the suspension is flexed up,
the leaf will hit the pitman arm (actually hit draglink end
joint first). Hence a very high lift will be needed to do this.
In addition, there are many advantages to using a coil spring
setup vs a leaf spring setup, such as:
coil setup will hold up to weight of 60 front and 44"
boggers (tested by me :-)),
usually flex better.
ride 1000 times better than leaf. Even with 200 lb (each)
tires, my bronc is not horrible riding with Superlifts
9" springs (which is one of the softest, non-custom
made spring available).
do think a leaf spring suspension is tougher overall if you do
high speed desert pre-running type stuff, but then you would be
getting lots of air and the clearance issue between drag link
and leaf spring would be even more of a factor. I've heard of
some people chopping off the front end of a F250 frame and
welding it to a bronco frame (to use F250 steering box). You can
also just chop out and swap in the first cross member which is
really the big difference between the two of them.
vehicle modifications listed in this article and most other articles appearing
in ProjectBronco.COM are for off-road use only and on vehicles
that are not driven on the street. Any modifications made to a
passenger car vehicle or light-duty truck should only be performed by
a certified mechanic and approved for use by the Original Equipment
Manufacture (OEM) of the vehicle.