I have a set of h&r coilovers with a about 40k miles. Lately it feels like the ride is super bouncy and very uncomfortable to be in. I'm looking to buy a new set or can i rebuild these coilovers?

 

A coilover has the same components as the stock suspension - Struts up front, shocks in the rear and springs. The wear item is the struts and shocks. Same rules applies to those struts and shocks as to the factory parts or Konis, Bilsteins, Megans etc.

A blown strut or shock, will leak oil out of the shaft and you'll probably see some on the strut or shock body.

A strut or shock that is nearing the end of its life will loose its ability to control the spring movement so the car will 'float' and 'bounce' a bit over road irregularities. Its harder to diagnose on a coilover b/c the stiff springs keep the car from 'floating' as much.

You should be able to have them rebuilt. Most shops test them on a shock dyno prior to rebuild. Contact the manufacturer or the shop you bought them from. If they are a dealer, they will know how to handle it. I had my Koni shocks rebuilt last year for roughly $125 each.