swerving ?

[NEK5]

ok i think i`ve narrowed it down to this...could having my tires at 20psi be the cause of my swerving in and out of the lanes around 50mph on the highway?

 

[1985_K5_Silverado]

Yes, that (low or uneven tire pressure) is one possible cause of "poor directional stability". Also bad shocks, ball joints, loose wheel bearings, bad front end alignment, and a few other things.

Did you deflate them to ~20psi, or is the the first time you've checked them in a while? Is the front sway bar still installed?

 

[NEK5]

Yes, that (low or uneven tire pressure) is one possible cause of "poor directional stability". Did you deflate them to ~20psi, or is the the first time you've checked them in a while?

well my tires sayy 20 psi max

 

[1985_K5_Silverado]

well my tires say 20 psi max

Ah, I see (looked at your sig). One thing about tire sidewalls getting taller is that extra sidewall flex effectively loosens your steering feel a little bit, makes it a steer a little sloppier.