I have my car lowered and was wondering how you would tell if you struts are bad. Everytime i hit a bump i can hear a weird noise in the cab

 

If it is a "scrunching" noise, even over somewhat small smooth bumps...that's not good. It'll usually be from the front or rear. Both don't usually go at once. Since I lowered my car on stock struts the whole thing seems to amplify the road noise...but no scrunching

Oh btw...there is a suspension section that will answer most of your questions...