Hey guys. I am supposed to change the plugs on my friends 2000 3.9L V6 Dakota tomorrow and wondered if I could get a heads up on what to expect. I've never even seen under the hood of it before so I am going in blind! I did some looking online and read that you have to remove a few things.

Well guys, what all should I know?

 

well, you need six new ones.....

nothing special, pretty mundane.

 

Autolite 3923's run real well in the 3.9 and are only about $2.00 each, a little less if you can find them at Walmart. Remove the air cleaner and air hat assembly for better access and you need a 5/8" spark plug socket and a 4 and 6 inch extension for your ratchet. If the plugs in it now are the original be prepared for some difficulty in removing them. Put a little anti-sieze on the new ones and you won't have that problem next time. The one on the driver's side closest to the firewall is a bear to get to. Use the short extension and work the ratchet from below the brake booster. On the driver's side I always use a long pice of wire to wrap around the heater hoses and vacuum hoses on that side to hold them up out of the way to get better access to the plugs. I personally use a can of air that is used for blowing the dust off of electronics to blow the dirt and crap out of the spark plugs holes before removing them. Walmart and drug stores sell the air duster cans. Gap the 3923's at the factory gap if the engine is stock, you can go to .040 if it has modifications. I gapped mine at .040 and it runs fine and gets great MPG. All I have on my Dakota is a 180 degree thermostat and V8 throttle body though. If the spark plug wires are old, replace with new and put in a new cap and rotor button otherwise it may not do much good to replace the plugs. The rotor button and distributor cap with brass contacts from Napa work very well in the 3.9. Part # MO 26 and MO 28 I think. The Belden OE equivalent spark plug wires from Napa work great in the 3.9 too. They cost a little more though, here they are about $35.00 a set but still well worth the money. Don't forget to put a dab of dielectric grease in the boots on the wires.

These few things will get better spark to the plugs and your friend should have a very noticable improvement in performance and MPG. With time, patience and the right tools this is a pretty easy job on the 3.9.

Jimmy

 

the wires from napa are good wires, the premium ones. soak the plugs in pb blaster the night before to make your life easier when taking out the old plugs. and also if you'd like, remove the spark plug heat shields, they do squat. without them, the engine looks cleaner and also made it a hell of a lot easier to remove and install plugs. without them, you can thread the new plugs in by hand without stripping the threads, or use a piece of 1/4" inner diameter tubing to start threading in the plugs, so you dont strip them.