The Stovebolt Site Forums The Shop Area General Truck Talk King pin bushing advice!

Well I took apart my front end and after the learning curve on the driver side I cleaned up the knuckle and spindal. I was doing a dry fit and the lower bushing is really loose. What can I do for it to fit tighter? When I grease it will it hold it in the right position for the holes to line up? I really don't want to buy a new spindal! Thanks for the advice in advance!

Truck: 1958 3200 stock 1/2 ton

ApacheFiend,


Good question. Some of the lighter AD trucks have floating bushings in the spindles...yours isn't an AD but a Task Force, so I don't know if this 'float' deal applies to you.

The OD of the spindle bushing would have a turned groove around its circumference so the grease would find it way in regardless of where it was positioned. Is this how yours is!

If you are not suppose to have floating bushings, and your spindle bores are worn, a machine shop can make new bushings, and true up the bore slightly in your spindles for a nice fit. There might even be bushings available with a oversize OD for just this purpose.

So the answer to your question is, I have little knowledge on this subject and hope a TF guru pops in...maybe Red58!

Stuart

Well the bushings do have the groove on the out side. The shop manual says "make sure the holes are lined up" So I am unsure as to proceed or get another set of bushings or what. Can I buy another set of large bushings? One more thing, how do you install the caps? I did not remove any from the original pins except one on the passenger side. Thanks for the help atomarc!

ApacheFiend,

I can't offer anymore advice because I don't know if your spindle bushings are suppose to be a press fit or not. The comment from your book about lining up the hole in the spindle and bushing would lead me to believe that these are a press fit...otherwise they would move around at will.

My "guess" would be that if you have 'new' bushings that push into your spindle bore by hand, then your spindle bore is worn oversize.

This is a guess. Actual assembly instructions are needed to determine if this is fact or fiction.

Whatever the story is, your spindles are not junk so don't dump them.

EDIT. The '55 2nd shop manual indicates 1/2 ton trucks use the floating bushings...again, don't know about a '58.

Stuart

bump

ApacheFiend,

This doesn't answer the burning question as to whether they are floating bushings or not, but here is my two cents.

I have never understood the true mentality behind this floating bushing business. My feeling is the king pins should be a snug as possible, and that the movable joint between the stationary pin in the axle, and the stationary bushing pressed into the spindle is the best arrangement.

I would do whatever it takes to get bushings pressed into your spindles, have them line bored or honed for a perfectly straight tight fit, with a new pin. Assemble the whole shebang and be done with it.

You haven't mentioned the fit of the pin in the axle...this must a nice, true light tap fit.

Floating bushings in a spindle can only lead to wear between bushing OD and spindle in my estimation. I think this was a cost saving scheme by Detroit...just stuff them in, no reaming required.

Someone else will pop in with the real skinny!

Stuart

jb weld the bushing in whith the holes lined up

The 58 bushings are floating. Do not JB weld them in. The fit itself will be determined by the fit of the kingpin into the axle itself, which should be snug. The weight bearing is done by the thrust washer, and not the bushings themselves, which need to be free to pivot in the spindles.

My confusion with the floating bushing system stems from the fact the bushing can move in its housing..the spindle. This is counter to any standard practice. The bushing is always held tight in its bore, and its ID is the journal.

When the ID is worn, the bushing is replaced. If the OD were a slip fit in its housing, ideally the housing could lose its fit along with the bushing, then you would have to replace whatever piece held the bushing.

In a automotive generator, the two end frames are bored for bushings which are pressed in. When the bushings wear, the are replaced. If they were to be installed with a sliding fit, they could wear this fit, then the end frames would have to be replaced...not to cool!

If the install directions indicate you should align the hole in the bushing with the hole for the Zerk, to me that means they don't intend this position to change. This would mean that the bushing that is slipped into the spindle bore will stay where it is, and the movement will be between the bushing ID and king pin OD.

This makes sense. Having the bushing move or rotate in the spindle bore makes no sense.

I will end my rant and go for coffee now!

Stuart

Ok, but one more thing. The lower bushing is pretty lose in the spindal. I dry fitted it to the axle and their was almost no play. But the dang bushing will spin in the spindal if i turn the spindal back and forth. I am just unsure what to do about that. Can I buy over sized bushings that will fit with a little modification?

ApacheFiend,

I'm afraid my rantings have scared everyone off!

A oversize kingpin set only means the ID of the bushings and the king pin diameter itself are 'bigger'. The bushing OD would be the same. This is your dilemma, the 'hole' in the spindle where the bushing goes is worn oversize from age.

You can install that loose bushing with Loctite Retaining compound, J-B Weld, or some other type of high strength epoxy. This is a stop-gap measure and will probably fail in short order.

The other method is to do it properly. Because the ID of the spindle in question is worn too large, and not machined, it isn't round and it isn't a "size", it's just a hole!

Unless the bushings from a 3/4 ton rig and up are a little larger on the OD, you would have to have the spindle bosses bored at a machine shop and have new bushings installed.

This sounds difficult, but if you find a good machine shop and explain what you want, it would be painless.

If we keep plugging away at this thread, someone will undoubtedly pop in with some magic part number or such.

The bottom line for me would be how much energy do I want to put into this fix to make it right and "finished for good" so I could rest my mind and move on to something else.

Stuart

Thats it, I want to do it right and not half-way so I can have a long life from it. I think I will call up my machinist and see what he says. Thanks everyone!