Does "coil spins" = "coil springs"? If so, not sure how psi. Maybe he was referring to lbs per inch of travel. Which springs do weaken w/ age. But the spring rate doen't change that much, they just start to sag. Unless you have a lot of miles on it, I wouldn't think your springs would be that weak.

 

thank you, there is not much mileage and I bought by a GMC dealer, so I trust the odometer is not modified, probably the previous owner used a one of those trailer attachment without wheels (for luggage or something like that..... and the rear suspension received allot of weight ...... I guess.....<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
This is what I’m gone to do<o></o>
First I'll make the change of the coil springs/spins, test the bouncing...<o></o>
Then I will add the bags I mention before, this because I will trailer a heavy boat, close to the maximum capacity of the truck.<o></o>
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I'll keep the forum updated on my findings.<o></o>
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just a final note, the bouncing problem is till the point to my lower back (lumbar bones) hurts me when the trucks moves/bounce to the sides (when crossing non a perpendicular bumper or train rails in the road), hope I explained myself well here.... so yes is a problem...<o></o>
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problem solved.
new coil springs and bags in side of them
so stiff as possible.
thanks fo the help.