The Stovebolt Site Forums The Shop Area Engine Shop King Pin bushings.

By chance has any of you Bolters ever replaced a set of king pin bushings in your straight axle while still bolted in the truck? Sounds pretty crazy to me? Thank you..

ol'55,

The bushings are located in the spindle which is taken off for this procedure. They are small and can be transported to the bench for any work while the big heavy straight axle remains bolted to the truck.

Stuart

I know it CAN be done this way but that big heavy straight axle is really easy to remove, which in all probability will be required since you'll most likely wind up taking it to a machine shop with a big press to get them out. You can just unbolt the steering arms, leave the drag link and tie rod attached and just lay them on the floor. I've seen a post or two on this site where you can use the weight of the truck to help push a stubborn pin out but that didn't sound easy or safe to me.

Just my .05 cents worth (2 cents adjusted for future inflation)

I'm not sure what atomarc is saying, but I will go along with waldo53 on being easy or safe while being in the truck. Ijust thought possibly there might be a portable press that would work.Also what actually determines if you need to replace your front king pins? Thanks there Bolters.

I tried on mine and was only able to get one spindle off. The other one required a 12 ton press.

ol,55,

I must not have understood your question. King pins are replaced all the time while the axle is still on the truck. This is true only if you can beat the pins out of the axle. You then can remove the spindles which are the piece that have the bushings in them. The spindles can then be machined and/or repaired as needed, all while the axle is still in the truck.

If you aren't successful at getting the pins out, remove the axle. If your axle eyes are oversize and need machining, remove the axle.

If you can grab the naked spindle while it's still attached to the front axle and are able to move it in a up/down motion, your bushings or axle eye is worn and it's time for a tune up. Does this make sense.

I have never seen a portable press for pressing the pins out while the axle is bolted to the truck.

Stuart

At my work... an international garage, we have a portable press. It has a small cylinder maybe 1-1.5 ft. long and a 5 ft. hose to the actual press part to push the king pin down through the bottom which is circular to let it threw. It is an extreme pain in the a&&. I know the big trucks are a little different but it's the same concept. I couldn't tell you where to look for a portable press. The one at the shop is pry over 30 years old. Typically though the pin is beat out with a sledge hammer and a homemade punch (a 4 ft. 1/4 in pipe with a bolt slightly smaller then the pin welded to the end.)

Once the pin is out, the spindle is taken to the bench to remove and insert new bushings as mentioned above. Not sure as to what truck you have, but on my '52 3600 the bushings have to be expanded manually to fit snugly.

Our company used to make small trusses for garages. We used a portable hand held mechanically powered press to mate the truss plates. Not sure anymore how it worked but it must have been cheap for the small amount of trusses that were made.

cshamel, could you explain how you reassembled your kingpins? or do you have a link to your experience. In particular, how did you "expand" your bushings?

My local NAPA store has an in-house machine shop. I am ordering the kit and letting them "do their thing" on the whole axle. Tear it apart and put it back together.
In my shop manual on page 3-9 it shows a PICTURE of what looks like a tap, called a reamer, put through both bushings in the knuckle.

I don't see where anyone mentioned the lock pin that holds the king pin in the axle. It might be covered with grease, and therefore is easy to miss if you don't know about it. The pin is tapered with a nut on one end, with the other end slightly rounded and recessed in the axle. You drive the pin out then you can drive the king pin out of the axle. Support the axle as close to the spindle as you can get, so the springs don't absorb the hammer blows while you pound on the king pin. If the king pin is frozen in the axle, then you will need to take the axle to a shop that has a press large enough to press the pin out of the axle. The new bushings are either honed or reamed to fit the new pins, although some light-duty king pin sets have "pre-fitted" bushings that work. If you are doing this yourself, make sure you align the grease ports in the bushings with the grease hole in the spindle. Otherwise you new pins and bushings won't last very long.

Harvester