how do I know if my leaf springs are worn out on 94 Suburban?

290,000 miles. The truck doesn't look like it's sitting low, to me. They make slapping noises because some of the plastic insulators are gone, though I replaced all the ones I could get to (8 or 10) without
putting the springs in a press and disassembling them. I can't get 4 of them out, the H-shaped ones.
Is there a typical life for these springs?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I traded my '94 Suburban K1500 6 years ago with 175,000 on it. Had the Z71 and trailer towing package, and the rear leaf springs on both sides had cracked and broken leafs from normal use at about the 7-8 year mark. Spring shop fixed them. It also sat down a bit lower in the rear at this point too. It wasn't used to tow anything, just my wife and two kids. Did a fair bit of hunting and moderate off roading in fall. The odd heavy load for landscaping or to the dump. My experience is that the rear springs do "wear out" over that amount of time and miles.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.