I recently bought a 02 Ram 1500 5.9L 4x4 Mega Cab with 150,000 for cheap. Are there any common problems that I should be looking out for or that problems are inevitable? Thanks

 

I will move this to the 3rd gen section for you (2002-2008 model years), since that is your body style. However, you may want to take a peak at the 2nd Gen (1994-2001) area's FAQ section in addition to the 3rd gen's, as you have a 2nd Gen powertrain. The 2002 model year was a "crossover" year, so to speak.

 

Gas engines only go for so long and with yours having 150k, the time is coming. No one can say for sure how long or far you can go but the odds are against you with 150k. I would never buy an engine with that many miles unless it was rebuilt recently or was very cheap.

The first thing I would do it treat it like no maintenance has been done to it and replace all the plugs, plug wires, air filter, brakes (if needed), engine/trans/front & rear axle oil, ECT

 

You may experience the notorious intake manifold plenum gasket leak. It causes oil consumption and pinging under hard acceleration. A timing chain set replacement might be in your near future.

I have a 1998 Jeep Grand Cherokee with the 5.9L (360 c.i.) engine and 165,000 trouble free miles. The plenum gasket was replaced in 2003 with 68,000 miles. Still on the original timing set and still running strong. The transmission (46RE) was rebuilt a couple of years ago at 135,000 miles. Only because a trouble code popped up regarding the torque converter. It was still shifting fine but I did not want to be surprised by it going out all of a sudden. Good luck!

 

the thing is the 5.9 will ast forever keep up with oil changes and tune up and these trucks will go over 300,ooo without a rebuild.

things that go bad is the plenem which will make the truck run like a dog and also 5.9 are known for cracked heads.

also dodge put a death flash on 2000-03 5.9 too try and fix the plenum failure to fix the ping . get a tuner from sct from hemifever and it will feel like a new truck with the newfound power !

these trucks are very picky on plugs also , change em too autolight 3923 for great throttle responce .

i just changed my manifold out to the sigle plane airgap. i love the new pwer and sound it puts out ! !

 

my dads got a 98 chevy truck with 230k miles and its still running strong. keep up with normal maitance and you should be fine. tho it all depends how well the person before you took care of it

 

i have 100,000, the only thing i had to fixe was hoses, spark plugs, t stat, radiator and battery.