Your pickup can shake at an idle for a few reasons, the most common that we see is from a misfire on the engine. It can be from your spark plugs misfiring or if your drive a diesel it would be your injector misfiring. Either way if it goes on to long it can damage your engine. We would suggest to have it checked to make sure there isn't any damage.
Give us a call and let us take care of you.
Happy Adventures,
Heather