Have a 98 S10 Blazer 4x4. It had been quite some time before I paid attention to the maintenance. Well with that said I have made it a point to replace many parts to include the suspension; pitman arm, idler arm, inner-outer tie rods, control arm bushings, sway bar bushings, shocks, lower-upper ball joints, sleeves & links. My issue is when it hits around 40-50mph it begins to shimmy. Not consistently but intermittently. Any and all suggestions are welcomed.

 

Get the steering parts replaced and it'll likely fix that issue. If there is a lot of slop in the steering components, it can cause the truck to want to wander around and even shimmy.

 

Great. Will give that a shot. Thanks much!

 

I would also check the balance on the tires