sdmartin65

Change the bushings at Ibeam to frame and radious arm to Ibeam. If you are getting excessive backup lean this is all that's left to change, as stated a minor amount of lean will always be present by design. These two bushings are rarely changed because of the amount of work required to do so. Their life has to be similar to the rest of the front end components.

RLXXI

There are no radius arm to I-beam bushings, the only bushings on the radius arm are at the frame brackets. Other end of radius arm is bolted metal to metal at the beam.

Radius arm bushings I have changed by the hundreds of dozens. Very easy to spot when they are bad and any alignment tech worth his weight will see that. The I beam to frame bushing how ever are often over looked. Not by me but yeah I can see a tech out for a quick buck just not even bother to check them before an alignment.
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stxlt

Lots of things to check, it seems. All part of the fun of owning a truck with a few years on it!