I just did a tire rotation on my 2003 6.0L Excursion. Afterwards, I took the vehicle for a drive on the freeway at 65mph. The steering was difficult to control and lightly swerved left or right, similar to the feeling of being blown by a strong crosswind. It was more difficult to stay in the center of the lane, and definitely required two hands on the wheel. It wasn't dangerous, but it definitely felt different and was pretty annoying. I did not have this problem immediately before the tire rotation, so am assuming the rotation is the probable cause.

I did the rotation myself, and hand torqued each lug to 150 lb/ft.

I have new front wheel bearings (1 month ago), new Rancho shocks and steering stabilizer with MyRide remote set at 7 front, 8 rear, Roadmaster Active Suspension, no rear sway bar (yet), and 31" tires with 5000 miles on them.

Any ideas would be much appreciated!

 

Just like with new tires, once fronts get 'worn in' and rounded, changing to the more 'square edged' rears or new tires will make it 'grab' the road surface with the edges a bit more and feels different...

also, did the air pressure change from front to rear - air pressure changes always made our Ex's change a bit..

when I got new tires after 95k miles on originals, I had to get used to the ex all over again.... then it seemed like the new normal

of course that assumes nothing is wrong mechanically - like did you break a tie rod

 

That's a good point, jdadamsjr, and it makes sense. I've only had the Excursion for a month and this is the first tire rotation I've done on it. I guess the sheer size and weight of the vehicle is what's magnifying this rounded vs. square tire effect, as I've never noticed it like this before on lighter vehicles. But with the X, the much worse drive-ability after tire rotation has really gotten my attention.

To answer your tire pressure question, I haven't been able to find good advice on this yet. I have 65 psi (the sidewall printed limit) in both fronts and rears. I was trying for better fuel mileage. Am I screwing something up by running tire pressure this high??