 If you haven't replaced those, they definitely need. You should be replacing your shocks and struts about every 60,000 miles because they just wear out. The fluid becomes thin. They've made the seals where they don't hardly ever leak anymore, but the car becomes bouncy. And one of the ways you can tell, we don't have a lot of bridge embankments, but if you go over a bridge or something that bounced, does your car keep bouncing? If it keeps bouncing, you know that the shocks have just worn out, and that would be something you need to replace. At 300,000, I'm sure you need shocks and struts.