King Pins

[mcarlson11]

I just put kingpins in my truck (f250) in February. I used bronze bushings, and I had them Installed and reamed at a machine shop into the spindle. I checked the fit and it was snug. Now I always grease them every couple of weeks. I checked them today, and they are both sloppy again, like I never touched them.

Why did they wear out so fast?

[fordman]

thats wierd. how sloppy are they does the tire move in and out at the top or bottom? or what are you calling sloppy? maybe you used a bad grease. i doubt it but it could happen i suppose.

[fmartin_gila1]

Normally, They will last forever if kept greased. By chance, was the last set so worn that the hole might be egg shaped, thusly providing no support to the bushing?
Fred

[Banjo]

I just did mine, so don't have much practical experience to share except that I was able to tap mine home with a brass drift to get them into position. Was looser than I thought would be good, but the guy at machine shop said he'd done them before and you shouldn't have to fight to get them in when they are fresh. He said the fight will come in on it's own later on when corrosion and wear set in. They DO make oversize kingpins, check NAPA. They don't even sell them by application where I live (at NAPA) they have sets by sizes!

[cdherman]

You are sure the play is in the king pins and not in the spindle itself? Just a though, as I assume you repacked the wheel bearings when you buttoned it all back up, and sometime, things loosen up a bit.

Other thought -- machine shops tend to just use a hone if they don't have the proper sized reamer. The problem with a hone is that they just keep honing till the pins fit, but if the hone is not just perfect, the hole will be tapered or ovaled.

That would result in faster wear. But even then, 8 months just seems WAAYY too fast.

Good luck.....

[FORDification]

I was also gonna ask you about that....if you were sure the slop was in the kingpin and not the wheel bearings. They can appear very similar, when rocking a wheel.

[mcarlson11]

I will double check that it is not a wheel bearing, but I swear I saw the spindle move and not just the tire. And this is movement at top/bottom.

I use Lucas grease, really good grease, actually one of the best.

The old king pins were not that worn out, about like it is now.

Machine shop used the correct reamer, I asked before letting them do it. I was able to tap kingpins in lightly with a hammer when I installed them which is normal.

[Banjo]

I'm anxious to hear what you figure out, because like you, I was able to tap mine home fairly easy, using a brass drift with no hammer, just arm strength and I thought it was far too easy and it concerned me. compared to how hard it was to hammer out 2 sets by hand (nearly had a stroke doing that). maybe your wheel bearings have backed off? You didn't forget your cotterpins and little weird lock thing on them did you to keep from backing off.

[cdherman]

It occurs to me that the hole through the axel, which normalls sees no wear at all, could be ovaled out as well. A new wedge or "keeper" might have held the new kingpins stable for a while, but then loosened up.

Did you try snugging the keeper? If you are able to snug the keeper and the play goes away, then you have a problem.

Just thinking out loud here -- I have not read or experienced this particular idea......

Good luck

[mcarlson11]

Fixed the problem. The nut that holds the through stud on had loosened up quite a bit. I snugged it back down, and no more freeplay in the king pins.

That also got rid of the loud annoying shuttering/sounds like every body panel is loose sound the truck would make every time I went over a bump.

[cdherman]

Fixed the problem. The nut that holds the through stud on had loosened up quite a bit. I snugged it back down, and no more freeplay in the king pins.

If I am following you, your problem was exactly what I had theorized it might be. We obviously used different terms for the parts, but basically, the concept/problem was that the king pin was not firmly attached to the axel (as opposed to spindle).

I would worry still that your axels are worn or ovalled out. I would check those nuts on your "through stud" regularly.

But lets be optomistic here -- maybe they were never snugged down right and this will be the last time for the next 100k miles.....

[AlleyCat]

The ends of the axles can wear.I've never seen a Twin I Beam worn as such but I have seen many medium/heavy truck front axles with worn king pin bores.It is usually refered to as bellmouthing.The axles can be repaired by a machine shop that is set up to do them.The axle is held in a fixture and the king pin hole is bored oversize then a steel sleeve is pressed in to bring it back to the original diameter.

[Banjo]

The non-nutted side should pull completely inside and be below flush when fully tightened, as those keepers are designed to pull in real far and wedge and I think they are really only supposed to be used once, but I might be wrong on that. I know I've removed 3 sets in last year screwing with old front ends and the non-nut side was way on up in there and head covered with mud/clay, so it was really hard to see from backside of beams.

[mcarlson11]

I know the hole is not worn out, they are brand new I beams. The kingpins probably was not 100% straight when I drove the pin in, and it straightened itself up over time. I will keep checking them for a while, just to make sure the pin doesnt loosen up again.

On the truck side of things, I do kingpins on Semis all the time. Its my job. I know a guy that can reweld the kingpin bores in a spindle/ axle. I can usually do 1 side of a truck in an hour, wheel on -kingpins- wheel back on in 1 hour.

[MustangSteve]

Just read your post on worn/loose kingpins. I finally got to the part anout NEW I-beams. Do you have the DJM dreambeams? If so, they are routinely machined with oversized holes in the beam end, and no matter hopw tight you tighten the wedge bolt, they are still going to rattle around in the bore. I just bought a new set and the hole is 0.010" oversized from an original I-beam. I am hesitant to install mine. Please reply if you are using the dream beams. I would like to get more info together on this and designa cure for it.