I have a leaking shock,so do I need to replace both sides? Also what indictes springs are worn?
The car has 91K and is 97 model accord,Any imput on this subject is appreciated

 

Shocks should always be replaced in pairs unless it is a brand new car or new shocks, with one gone bad. Ride height is measured to indidcate springs are weak.

 

When you have the springs out and off the damper, place each pair of springs on a flat surface and carefully compare each pair of springs for equal height. It would be unlikely for both springs to sag entirely equally, so if one spring is shorter than the other at least one spring is sagged, and maybe both (but one less than the other). If they are both exactly the same heightthen it's likely they are not sagged (stock Honda springs are very good quality springs and less likely to sag over time than some others).

This doesn't utterly rule out both springs having sagged equally, but if they are equal lengths at least they will be supporting that end of the chassis equally on each side.My understanding is that asagged spring will retain it's spring rate (until it's near fracturing), just provide a lower ride height. This isn't a big problem if you don't mind the lower height, and both springs happen to be equally sagged. However if only one spring is sagged then the chassis will be unequally supported at that axle line and one spring will be effectively more 'pre-loaded' than the other, one wheel will be carrying more static weight than the other, and the car will probably handle differently in right vs left corners.

 

To put it in perspective, my old stock springs had 225k on them and were just fine. At 91k I think yours should be just fine.... unless you go off jumps lol.