Spring Bushing Replacement

International Spring Bushing Replacement
by Dan Nees, Dennis Petterson and Ray Cass

A big problem with Scouts in particular, and Internationals in general, is their spring bushings deteriorate. When this happens the trucks really wander and steering becomes very erratic.

The way to fix this, is to replace the rubber with Polyurethane bushings. There are a couple of different styles and brands of bushings. The two main brands are, Energy Suspension, and Prothane. Another brand makes a re-greasable bushing for the shackle end of the truck as well, but; their name eludes me. Either brands work fine, and the greasable ones, while I haven’t used them, sound intriguing. You can purchase these items from any Light Line Dealer, such as Super Scout Specialist and the greasable shackle bushings can be bought from AT Scouts

The tools required are rather basic for the simple mechanic. More advanced tools make for an easier job, but are not required.
Basic Tools:
Hacksaw
Hammer
Chisel
Electric Drill with a lot of small drill bits.
5/8", 11/16" and 3/4" socket and wrenches
PB Blaster, or similar penetrating fluid
Jack and Jack Stands
Jug Wrench

Advanced Tools
Sawszall
Impact Chisel
Impact Gun
Oxy-Acetylene Torch or Propane

Step 1.
Jack up one end of vehicle and support securely with jack stands. Remove the wheels.

Step 2.
Unbolt the Sway Bar if you are doing the front axle. This requires 2 3/4" wrenches and a lot of strength as these bolts are usually tight.

Step 3.
Unbolt one side of the axle, shackle and frame side bushings, using the 5/8 and 11/16 wrenches and lots of PBLaster. You may find that some of the bolts will be frozen to the inner sleeve of the bushings. If this happens on the frame side bushing it will require torching, or cutting to get the eye out of the frame box. If it is on the axle side you can always get at least one shackle side off so you can work on the bushing.

Step 4.
Using an electric drill and a small drill bit, like 1/8" – 1/4", and drill the rubber out around the inner sleeve. Alternately, with a propane torch burn the rubber out, or with an oxy-acetylene torch burn the inner sleeve out. (WARNING) If you use propane or a torch, be sure you do not have any fuel leaks, or are near a fuel line. (WARNING) If you use an oxy-act, the inner sleeve can get so hot that the rubber can "SHOOT" the sleeve out of the eye. Do not sit facing the eye. With the rubber cut, or burned out, you can now push the inner sleeve out of the eye. After letting the rubber cool a little, push that out as well.

Step 5.
Now, take a hacksaw and thread the blade through the eye. Make 2 cuts about a 1/4" apart. You do not need to cut all the way through the outer sleeve, but you should remove enough material that the sleeve will tear out. If you have a sawzall you can use that to cut the outer sleeve. Using a small cold chisel, use the chisel to roll the small cut piece’s edge up and follow it all the way into the eye. With that piece cut out the rest of the sleeve will collapse in and can be pushed out.

Step 6.
When installing the new bushings, apply the silicon grease supplied liberally to the outside, inside, and inside the steel sleeve of the bushings. If you really want to do it right buy K2 silicon grease from NAPA and really slop the bushings up and install them in the now empty eye.

Step 7.
When replacing the spring you MUST replace the old bolts with new Grade 8 bolts. You can go to a hardware store and buy 12 7/16" bolts, or you could buy an entire bolt kit, including new shock bolts, from East Coast Scout Parts for $32 plus shipping. This kit contains the 12 Grade 8 bolts, nuts, and washers and are zinc plated. It is also cheaper than buying individual bolts from a hardware store.

Step 8.
When tightening the bolts upon re-installation, do not tighten more than 20 or so ft-lbs. The rubber bushings that were stock called for a high torque factor, like 60 ft-lbs, the urethane will not flex properly with a high torque value. Hand tight is sufficient. You will have to wait till both sides of the front axle are done to re-install the front sway bar.

Step 9.
Re-install the wheels and move on to the next axle.

Another way to do this job would be to remove the entire spring out from under the axle by removing the u-bolt. This would allow you to work on the spring out in the open. However, if you remove the u-bolts you MUST replace them with new bolts. The 3 corners are 3" diameter 1/2" thread u-bolts with the passenger side front corner being 3 1/2" diameter 1/2" u-bolts. These will have to be custom made as you cannot buy them this size in the store. Call your local spring shop and ask of they can make you u-bolts. What you want is a 3 1/2" diameter bent on a 18" over all length, end to end, rod. No matter how tempting it may be to re-use the old u-bolt DO NOT. They are vital for holding your truck together and the price of buying new bolts, about $60 for all 4 springs, is cheap insurance.


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About jimhadfield

Retired and enjoying it.
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