When should I replace the shocks and struts? The ride feels rough to me, but the car does not bounce.

if you see some wear that is not normal you should change them

Shock absorbers and struts attenuate the bounce and keep the wheels planted. People replace them when the vehicle "floats" on the highway. The springs carry the weight and dictate how the ride feels. When they wear out, the vehicle sits lower, has reduced suspension travel and has a tendency to wear out the insides of the tires. --- The Highlander is truck like and it has weight. It has strong springs to hold that weight. If you want the original ride, replace the springs, struts and shocks. It shouldn't cost much more (other than the cost of parts) than replacing the shocks and struts.

After reading postings on numerous websites that imparted very little information, I was happy to find this one. It is a clear, logical explanation with educational value for the novice. Thank you!

I was told that the suspension pads need to be changed because it won't pass inspection without this. I have already had the alignment done, i was told by the shop that this shouldve been enough to pass...but it wasn't? Ive never heard of suspension pads??? Is there a cheaper solution, I don't have $1500!