Popping in steering

[t700]

Last week when coming to a stop felt a popping in the steering.
Took it to a shop in Rippon Ca and tested the steering linkage & replaced the
drag link which had excess movement.

Did not fix the problem.
It only does it after the truck heats up under load.
Does it intermittently mostly when pulling hills whether turning the steering wheel or not.
2011 T700

Any thoughts on how to narrow down the problem?

Thanks T700