new Jeep owner with questions
 

Hi All,

I bought a used 98 Wrangler and have a few questions

1) what is the recommended RPM at idle

2) I have a knock coming from what sounds like under the body by the
passenger frame rail by the exhaust pipe...I held the pipe while it was
idling (and still cool!) anyone have any ideas why i am getting this
knock or suggestions on what else to check?

3) Is there a primer on how and when to use the 4WD settings...my jeep
did not come with a manual (anyone know where to get one online for
free?)

Thanks in advance!