The four u-bolts nuts on either side of the rear axle were under-torqued.
Suspension
GMC C35 Suspension problems by year
1 complaints filed with NHTSA about the GMC C35's suspension. Broken springs, struts, control arms, ball joints, noises and alignment that won't hold.
Suspension complaints by model year
Suspension recalls
Trucks were assembled with the left-hand lower control arm to frame rear nut tightened below the specified torque. Low torque on this nut may allow the attachment bolt to loosed and subsequently fatigue and break. The bolt breakage can cause the left hand...
The left hand lower control arm can crack starting at the rear flange and progressing to the ball joint mounting hole and eventually cause the lower ball joint to separate from the control arm.
The left and right front suspension crossmember strut rods, which give added strength, may have been omitted during assembly. Consequently, a frame crossmember crack could eventually develop at the forward vertical front suspension bolt.
Latest C35 suspension complaints
Passengers side lower control arm failed prior to recall, repairs refused for d rivers side broken control arm (91v-217). *Ak
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data