I've got a '72 F-100 4x2 that is exhibiting a few front-end issues that I am asking for some help on:

1) I think the kingpins need to be replaced -- when I jack up the front end, I can grab the top and bottom of each front tire and rock it and get what feels like about a 1/2-inch of play. Not nearly as much when I grab the left and right side of the tire and rock it that way. Would that be the indication of needing to replace the kingpins? And I hear there are choices of either bronze or nylon -- I assume bronze is the way to go?

2) Noticed the radius arm bushings are cracked, so of course those need replacing.

3) Steering is a bit odd - the truck seems to wander a little and it takes some concentration to keep it centered. Tire pressures are within spec, the tires are only about a year or so old with less than 1000 miles on them.

My dad has owned the truck since new, it's never been in an accident so it's in pretty good shape. Running stock tire-size and original wheels. Just replaced the shock absorbers -- they were about 15 yrs old. Replaced with Monroe Gas-Magnums. I assume before I start dealing with getting the front-end aligned or messing with the power steering gearbox, I need to possibly deal with the kingpins? Axle pivot bushings? Radius arm bushings? ....Is there anything else I should consider? Drag Link? Tie rod ends?

 

The bronze kingpin bushings will last longer than the nylon ones but you'll have to get them reamed (machine shop work) to match the new pins. Not a big deal. Just take the spindles, new bushings and kingpins to the machine shop and tell 'em to make 'em fit. It'll make a HUGE difference in the way the truck behaves and how the tires wear. If there is any play in the radius arm because of bad bushings, that will cause you to wander around the highway so it sounds like you're on the right track there, too.

 

JJ, I wouldn't touch em. I would instead look for a 73-79 truck to use as a donor for power disc brakes, & newer power steering, and possible transmission swap if you wanted to. You can replace those kingpins or other pieces, swap it in under your truck bolt hole exchange and have a nice upgrade for your truck.

I have bought several donors in the past, sold parts that I din't need on my truck for more than I paid, so my parts were very affordable.


my 2




John

 

My truck is behaving the same way.. I have half the front end on the ground as I am in the process of replacing the radius arm bushings, pivot bushings, inner / outer tie rods, drag link and was going to do my kingpins but I since I have no play I am just going to leave them in place for now.

oh almost forgot, i am replacing the rear leaf and shackle bushings.

The rear are ploy but the front are OEM style, don't know if i am wasting my time or not...

Will let you know how she tracks after i am finished..

 

The play could also be wheel bearings, have someone grasp top and bottom of tire and move while you watch to see what's actually moving. Replace radius arm bushings with polyurethane. John's idea is a good one, 73-79 i-beams with disc brakes. Just make sure the donor doesn't need king pins as well.

 

who sells the poly bushings?

 

Energy Suspension, should be able to pick them up at an auto parts store.

 

Hey guys, thanks for all the feedback. I've made the decision to keep this truck as stock as possible which means I will keep the four-wheel drum brakes.

 

I had he same problem – this helped - (Touch the basics first) – clean up your steering box sector shaft threads and mark the slot – on the adjusting screw (common blade) - advance – ¼ turn. Drive to please or mark to full circle. Power steering under 15 Lbs is very hard to tell, if it gets to hard to turn port or starboard, you’ve gone to far.

 

The adjusting nut on the gearbox sets the preload for the sector shaft...only.

If you mess with it...be aware that the gearbox may lock up tight. Now, you're in a world of hurt, because once it's locked up, backing the nut off won't help a bit.

 

Something else to look at would be does the steering self center (within reason)? If not the king pings (at least 1) is freezing up. Comes from not keeping them greased. The fix is replacement. Definitely go with bronze bushings.

 

Finally done. New radius arm bushings, bronze kingpin bushings, axle pivot bushings, drag link, center link, tie rods, and alignment. Drives MUCH better, perhaps close to the way it did when new?