3" is the max without some further mods. You will eat UJ's for the prop though. Watch the cross member the rear prop runs over the top of, on my 2.8 it kept hitting on large articulations.
One of the reasons I wnet LWB is its easier to go bigger.
Fronty no.4, pimp mobile Treg 3.2 LWB lifted 2.5"
Fronty no.5 2.8 swb hd coils +2" 31"machos.