Id start with balancing the tires

 

I would definitely start with balancing. Don't do stick weights. My guys cannot get it right went back 3 times finally told them to add rim weights. Finally they got it right. It depends who you get those untrained young kids just don't know what to do. It's just not put the tire on the machine and hammer a weight on.

Or bent rim. Do you have 20s or 22s?

 

Whew....it's pretty open ended on trouble shooting a shake at higher speeds. Like stated above....out of balance tires, or bent rims are one of the first things to consider. It's always a process of elimination for this type of issue. Other things to consider: Belt separation on one or more tires, bad tie rods or ball joints, bad shocks, alignment issue, dragging brake caliper, Heck, even an issue with a drive shaft can cause shaking at higher speeds.

 

Start with finding a good tire shop with a Hunter Road Force Balancing machine, and with your high miles you will probably need some front end parts, more so if you have 22's vs 18's

 

balancing worked

 

OP both of my rear wheels on my F-150 had mud inside the wheels and it caused the truck to shake at 80-110km/h. Cleaned it off and it drove smooth after that! I would definitely check that out and then re-balance your tires.

 

I get the same trouble with snow pack over the winter months.

 

Sometimes the rim is bent and all the balancing won't work but then you can rotate them and it should fix it (putting bent rim in rear theoretically)



Never had to have my rims road force balanced I know it's a pain to do and some shops charge 150-200 when regular balance is 20 all 4 or 15-20 each at Mavis firestone etc. these young kids don't know what there doing you need to clean the inside of the rim area before you stick the weight on or it won't stick right. Common sense

 

I get troubled in winter

 

I get troubled in winter

What size rims