Another. Hopefully minor issue
 

Ok first 4wd issue..solved
then wife called....no crank
NOW ! ( happened to me once sitting at idle )
She told me while headed home this am, driving along cool as can be, then .BOOM !! Tach shot to about 1k .Rpm above what was driving at for just like 1/2 .Sec or so.... Any ideas ???

Seized water pump, stuck thermostat. Start with the thermostat...

The tach shooting up like that makes me thing it's something with the transmission. Like it slipped for a second.

I know on mine, when it's pretty low on atf, the torque converter won't stay locked. It'll unlock and lock randomly, resulting in the RPM shooting up for a second or two, before coming down when it locks back up

sounds like the TPS have it scanned for codes.