No, V-6 was introduced in 2007, the 2004 Rubicon would have a 4.0 Liter I-6 (Straight Six Cylinder) Hope this helps.
Straight 4 or straight 6
The thermostat on a straight 6, 4 litter Jeep Cherokee is located on the very front of the engine. Just follow the valve cover to the front of the engine and you will see the thermostat housing it has two heater hoses coming out of it (one to the radiator and one to the heater core). Simply take out the bolts holding the housing on and remove the heater hoses and the thermostat will pry right out.
I know from owning two that at the very least, some Jeep Grand Cherokees have straight 6 engine. i do not know about other models.
The 2004 Jeep Grand-Cherokee has an inline 6 engine.
The 2004 Wrangler 6 cylinder is a 4.0 liter.
6
It is about 190 f.
The thermostat is located below the alternator on the drivers side. The coolant sensor is right above the thermostat.
my jeep Cherokee 1998 4.0 is a straight 6
10w30
The 6 cylinder engine in a 2004 Wrangler X is a 4.0 liter.