So I am having fits with my 86 wanting to wonder going down the road. (it is 2wd)

Everything in the front end is tight. Ive changed one tie rod and adjusted the box. It is toed in 3/16"

It is an f250 light duty, so I put f350 springs under it. I think since the rear is higher it changed the angle of the king pins. I know on the straight axles, that if you shim them and roll king pins back that it handles a lot better. I don't know how that is supposed to be done on the Twin I axles?

 

I would take it to a shop and let them put it on the alignment rack. It's very hard to guess and use a tape measure to get things straight. You may also find the axles may need to be bent to get them into spec.

 

The king pins aren't seized are they?? I ran across that problem with my 86 F250. Turn to the right, truck wanted to keep going that direction until you turned to the left. Causing a wandering motion. Rt side was bound, replacing the king pins solved the problem.

 

I dont think the kingpins are seized. All four took grease. It drives fine on a nice road, but one that is rutted some it wants to follow the ruts more than it should. Generally when you turn and let go of the wheel it wants to go back to center, but this one just stays where its at and keeps turning. It didn't do any of this until I put different springs on it. I would love to take it to an alignment shop, but I haven't had good luck with the ones around me. Maybe ill take it somewhere else, but where those rods that support the axles equipped with different mounts depending on the truck?

 

Just from experience, I have thrown my hands up in the air and paid $60 to get it done right. I changed all my ball joints and tie-rods, the easy stuff. The 60 dollars is well worth knowing the problem will be done right and the blame can be shifted. Same thing with my breaks, I can do it but Id rather know I can come back at someone for not doing it right.

 

That is true. It surprised me when I went to one shop, and instead of just taking the car in and doing an alignment, they asked me what the problem was, and they test drove it before they took it to the rack. The impression I got from them was I was paying them to get rid of that specific problem. They swapped tires around and did some other things before finally getting it fixed.

The arms you are talking about are the radius arms correct? The ones that go back and mount under the cab? I don't think they made different ones for different alignment issues. Ever consider taking the springs in the rear back out? The springs on your lighter duty f250 are not the load carrying limiting factor of your truck. The rear axle is. You might consider airbags if you want to level the truck up some under load. I hate the way a stiff spring rides and handles under one of these trucks.

 

The old springs were broke and it was dangerous to drive. It doesn't ride too bad with the 350 springs on it. Yes I was talking about the radius rods. I figured the rods were the same, but maybe the mounts were lower for the larger trucks.

 

Taller springs in the rear means your caster is out of whack. Frame is no longer "level". By lifting the rear and not the front your caster is now too close to zero. Add a set of adjustable radius arm bushings and have it aligned. Auto zone has them in stock.

 

Duralast/Radius Control Arm Bushing FA7258 at AutoZone.com

Is this what you are talking about?

 

Yep those are the ones

 

What about the rubber bushings that connect front end to the chassis, (2). There are two, at least on the 1989 F150. Under the oil pan area. The shop wouldn't even align my vehicle until they were replaced and they wanted $700 to do it by the book. Did it myself.

 

Those will make it wander but Will not cause no return to center.

 

Good deal I will get a pair of those. I will look at the bushings on the front to see how badly they are worn. It is just a work truck so I don't want to put a lot of money into the front end. Getting the caster back where it needs to be will be a huge help. Like I said, it never did that before I changed the springs.