Liberty Springs

[peterb]

Hi,

What is the typical life of rear coil springs? My 2002 liberty with 180K miles, is getting a bit soft in the rear. I measured the distance from the ground to a point on my hitch with an almost empty fueal tank, filled it, and noticed a drop of half an inch, is this normal? The vehicle has never towed a heavy load, and the only consistant load at back, is my 90 pound lab.

 

[SteelHeadz]

Vehicle ride height audits should be performed utilizing the following procedure:

1. Drive the vehicle straight and forward on a non-tacky surface for a minimum of 20 feet to neutralize track width.
2. Bounce the front of the vehicle five times.
3. Measure and record the dimensions
   FRONT RIDE HEIGHT
   
   Front ride height is defined by the relative vertical distance between the spindle center line and the rear pivot point of the front lower control arm to cradle attachment. The spindle center line is to be measured at the outer wheel face (point A). The rear pivot point is to be measured at the center of the cam bolt (point B) at its rearward most end (nut end).(Front Ride Height Measurement)
   
   REAR RIDE HEIGHT
   
   Rear ride height is defined by the relative vertical distance between the top of the lower spring seat strike surface and the bottom of the jounce cup (true metal to metal jounce travel). This is to be measured vertically inside the coil from the point intersecting the inboard edge and the for/aft center of the jounce cup (point C) down to the strike surface (point D).(Rear Ride height measurement)
   Measurement Target Minimum Maximum Front Ride Height Distance AB 48.8 mm Z=996.81 - 948.03 38.8mm 58.8mm Front Cross Ride Height Left - Right 0.0 mm -10.0 mm 10.0 mm Rear Ride Height Distance CD Target:116.1 mm. Minimum: 106.1 mm. Maximum:126.1 mm Rear Cross Ride Height Left - Right 0.0 mm. Minimum: -10.0 mm. Maximum: 10.0 mm

 

[peterb]

Interesting info, but I would have to know what the specs are for the vehicle rear travel distance, and compare the difference to see if its within manufacturers specs.