annoying suspension noise

i drive a 2002 suburban with 12000 miles and when i am driving slowly, specially making a turn and the road is a little bumpy, i feel that something is hitting something and feel it on the steering wheel. took it to the dealer and they say its the intermediate steering column, it has to be lubricated or changed, took it to a friends shop and he told me its the pitman arm going from the steering box to the steering bar, does anyone know of a recall or service bulletin for this issue, the dealership told me that when this happened they had to change the expensive steering column, but now the factory issued a bulletin that with a special lubricant the problem is gone, either way they want to charge me for the repair, sounds like a defect to me, anyone knosomething that could help me

thanks

Eduardo Riojas
Monterrey,Mexico

There is a bulletin referencing your complaint #00-02-35-003B...It involves removing the intermediate shaft and lubercating the inner splines.
Don't know about warranty in Mexico, But if your truck is still under factory warranty, the repair should be no cost to you.

thanks, where could i find this bulletin or could you send it to me to my email,

found it, thank you very much for your help, is this just regular maintenance or is it a defect?