I just had my front end checked at my nearest dealership and learned (as expected) that I needed an alignment. All four tires have their outside edges wearing.

I am puzzled by the machine they used to determine my alignment. The attachments to each wheel had arms that grabbed the tire and not the rim. The "black cylinder-like objects" which are held near the rim are not firmly held in any specific position. I touched one and it moved relative to the arms that grabbed the tire. I don't understand how this can work. Any explanations??

In the past I've seen wheel attachments that affix firmly to the rim and that makes sense to me.


Background just in case:
2011 F-250, extended cab, short bed, gas engine.

~12,000 miles ago I finished towing a travel trailer 5,000 miles that seemed to have too much tongue weight and at the end of the trip I had the worn down outer edges on the front tires. I went to a nearby tire shop and they checked and gave the alignment a clean bill of health. They suggested excessive tongue weight and I accepted that. The problem is that the trailer was a 19', ~4,500 lb. Airstream Bambi and exceeding 600 lbs. tongue weight seems implausible. But,,, but,,, the trucks nose seemed to be in the air and in a sudden downpour I think I started to experience front end hydroplaning once.

It is now a couple of rotations later and the wear is on all four tires.

 

I'd take it to a alignment or tire shop t get it done with the right machine. I use to do alignments back in my dealership days and our sensors all attached to the lip of the rim. maybe you have lipless rims. if your are lipless then they should of used the adapter that goes in the wheel and presses out to stay in place

 

A nearby tire shop gave it a clean bill of health that I no longer believe. Admittedly it is a bunch of miles later but the the same symptom "infected" all four times since the rotations. Their "octopus" attached to the rims, not the tires.

These "floppy octopus" fittings were at an actual Ford dealership. My expectations are that they should know how to maintain their products.

thanks,,,,,

 

Both John Bean and Hunter have clamps that attach to the tire. It is only found on newer alignment machines. Perfectly accurate unless you run large mudder style tires with large lugs then tire flex can play a roll.

 

That's interesting. Still, I'd have expected the devices at the center of the wheel on the "tire clamps" to be solidly in place.

I am running stock tires so they aren't contributors to any mis-measurement. Also, you are surely right about new. The measurements are taken in the "intake aisles" where we enter for service and that is recent construction in this dealership.

I'm getting the alignment that I'm sure I need this morning.

thanks,,,

 

They used the same type of device on the rack for the alignment. I'm hoping that in 10,000 miles I recognize that the alignment was done right.