Front Suspension and steering Upgrades

[1986F150Six]

Interesting, I had a different experience. On my 2wd short box, I had 275/60/15 Cooper Cobras all the way around, 2" wheel spacers, and a completely rebuilt (minus steering box/shaft) front end including a Skyjacker stablizer, and the thing would take corners at 80 mph like nobodies business, without so much as a squeeling tire. I was confident enough that I actually took it out on Watkins Glen.

I need to clarify my comments a bit, because we're probably on the same page. I'm also running 275/60/15 Copper Cobras all around, but our roads are worse than yours, and with the ruts in the asphalt, the wide 60's series tires track with the ruts badly...so on that kind of road (which we have a lot of) the steering wanders quite a bit. When I was running the truck with the stock small tires, it wasn't nearly as bad. My old man's Infiniti and my wife's Lexus are the same...winter tires no problem. Throw the low pro summer tires and wheels back on, and they're tracking all over the place. On smooth flat asphalt, they all track straight and smooth.

The tighter RedHead box eliminated a lot of the wander, but the truck still tracks with the road (ruts) a bit. If I threw a set of 235/75/15's on it, it would probably drive perfectly.

Mine handles corners pretty well. One thing with those Ford steering boxes is that most of the slop is when driving straight. Throw them into a turn, and that is where the boxes are still nice and tight. We have some pretty twisty roads around here, and I must say, my steering is solid while turning. Driving straight down the road though...it still does wander a little bit.

Yes I do remember them having some bump steer going on that did improve with smaller tires, at one point I was even running 7.0-15 bias plys. I have looked into a redhead/bluetop box as well but that truck isn't worth putting that money into anymore.

Every truck I've ever had wandered in a straight line, eventually I just got so used to it that driving a brand new car made me drive all over the road.

I run stock sized [215/75 X 15] tires and have found that by running about 3 PSI less in the rear, the truck handles and rides the best. Normally, I set the tires @ 35 PSI in front and 32 PSI in back.

[Gary Lewis]

I run stock sized [215/75 X 15] tires and have found that by running about 3 PSI less in the rear, the truck handles and rides the best. Normally, I set the tires @ 35 PSI in front and 32 PSI in back.

That's a good point, David. Air pressure can make a big difference regarding following ruts.

The issue is where the tire is making its main contact with the pavement. If you have the air pressure set where the tire is hitting the pavement with equal pressure across the tire then the edges may try to follow the ruts. But if you increase the air pressure just a bit there will be more pressure in the center of the tread and less on the edges, and less tendency to "hunt".