I have a 91 pickup 4x4 and the rear leaf springs are what you'd expect from a 21 year old truck. My back passenger spring is pretty much flat and the back of the truck sags a little on that side . As of now I can only carry 400-500lbs in it without them completely just touching the frame. My question is should I just buy new leaf springs all together or are the add a leaf systems enough to fix the sagging problem and allow me to carry more weight? Thanks in advance.
Also if anyone has had good luck with the add a leaf systems what did you use? Or what does anyone recommend for new springs?

 

Personally I would replace the rear springs.
Some have had luck with the Zuk mod.
Tons of info on it..give the search a try.

 

big fan of the ZUK mod!!!