I was told that if the leaf spring appears to be flat (ie no arch) then it is time to replace them.
The spring appears to be even with the ground in front of the axle, but still has an arch in the rear between the axle and rear shackle.

I was also told that the stock factory springs are rated at under 900 lbs. I see that sdtrucksprings.com has replacement springs with a 1400 lbs capacity for $128. Wonder how stiff a ride these would give?

EDIT: '02 4dr 4wd

 

Usually, my springs crack when they're worn out.

 

usually a flat spring means time to replace or re arch. there was a place down here that did both of mine on my dodge ram for $60. Did that last summer and so far they are good. look for rearch prices before u buy new.

 

Is the re-arching done with the springs on the vehicle?

 

Check rear ride height, that will tell if they're sagged. Is it 2 door, 4 door, 2WD or 4WD?

 

Its my understanding that the front half of the spring does no springing, its just a trailing arm. Its the back half that deforms to make suspension compliance.

 

4dr & 4wd

check ride height?...compare left to right measurements or should there be a set distance between the top of the axle tube to the frame?

 

nope. you have to remove the packs and bring it to them.

 

Rear ride height is measured from the axle bumper bracket surface down to the top of the rear axle housing. Blazer, Jimmy, Bravada spec is 5.1 to 5.8 inches. Pick ups are 5.1 to 6.4 inches.

 

Made the measurement and well within range; so I guess they are not worn-out....just weak. Does not take much of a load to bring the backend down....couple of 60lbs bags of concret and its 5" lower at the rear bumper; have to watch it or I will hit my head on the glass door.

Perhaps I just need to replace the springs with higher capacity ones....but concerned about the ride quality if I did this...???