97 F250 Pulls right

I am trying to find out a cause for my 97 Ford F250 4x4 HD. It pulls to the right and will shake and shimmy at around 65 to 75 MPH. I've had ball joints replaced, front bearings replaced, new tires, balanced and aligned, and taken back and aligned and aligned. Still pulls right. Any Ideas out there?

TIA
jabentley:banghead:

How are the axle u-joints ?......Do you have a lift installed ?.....My alighnment guy actually fakes the settings to make the truck gently pull to the left...after about 7 seconds without your hand on the wheel....on interstate roads...once you are on county roads....goes straight as an arrow......

How are the axle u-joints ?......Do you have a lift installed ?.....My alighnment guy actually fakes the settings to make the truck gently pull to the left...after about 7 seconds without your hand on the wheel....on interstate roads...once you are on county roads....goes straight as an arrow......
No Lift kit, and no I have not had the axle u-joints looked at. Thanks for the reply!

jabentley

Have your front end guy set the caster about 1/2 degree more positive on the right hand wheel. I have always set them up for the vehicle to very slowly pull to the right when steering wheel pressure is released so that if they fall asleep driving the vehicle will go off the road to the right and not into oncoming traffic. Most manuals with specs have these settings for the castor. The same result can be had by setting the left wheel 1/2 degree negative castor. Tires with a slipped belt will give you the same result. To find out if a belt is slipped in your tires change the left and right tires. If it then pulls to the left you have a slipped belt.