When is it time to tune-up a 2004 Dodge Ram 1500 Hemi. I have 41,000 miles on it and it runs fine and avg's 15 MPG

1st tune (spark plugs) is 100,000 miles air and fuel filters every 30,000 miles

30,000 mile plugs but it doesn't meen they need replacement I work for chrysler I would wait till about 50 or 60 thousand remeber just because there is not a problem doesn't meen they should not be replace at the recommened intervals. they are considered a wearable item. when you do the plug do the wires. words of advise when doing the ignition wires do ONE WIRE AT A TIME it will save u from a big headache. Good luck.

You should replace your spark plugs at 30,000 miles if you have the owners manual and look in the maintenance section it will give you chryslers suggested maint..schedule but if you have a regular technican that services your vehicle and you trust this person have them do a 23 point inspection and see what needs to be brought up to date every car/truck is differant and because their is a certan amount of miles doesnt mean it automaticly needs to be done.the vehicles history needs to be known or if you gp to the same shop they should know what it needs also the hemi is a form of a waist spark system and takes 16 spark plugs compared to other v8 engines that take 8 spark plugs so expect to pay well over $100.00 probably $200-$300 based on where you go or if you live in ventura co. you can contact me $149.95