Hi All,
What are the best plugs for a 03 Hemi?
Thanks
Bob

 

I used NGK 5306s when I changed mine. Bosch are OK, but some folks have had issues with them. Don't use platinum, use good ol' copper core. If you're running any boost, you'll want a cooler plug (4306s, maybe). Remember, there are sixteen plugs. The back four are a bear to get to.

 

Just put the original champions back in. I found them at http://www.sparkplugs.com/. Just remember 16 plugs not 8.

 

Yup, I agree. Go with the stock Champions, the expensive plugs won't help one little tiny bit.

 

does the 4.7 have 16 plugs too? or is that only on hemi's? and does the 07 hemi have 16 as well?

 

The new 4.7ho has 16 right, but not for the 07.

 

Team

Honestly.. I have been runing Champion platinums for nearly 7000 miles now and I have not had a single performance, idling or fuel consumption issue from my truck. I tow a 4500lb travel trailer and a small 600lb trailer behind it with gear when I go out with my family and I have not had a single issue at all (knock on wood).
I am not sure why people have issues with the platinum plugs...

 

I have ran NGK Iridiums in my 4.7L and my Daily driver civic and noticed the vehicles idled alot smoother but felt no performance gain or gain in MPG.I would stick to factory spec and just get the stock Champions.Alot cheaper and you would get the same outcome than the expensive plugs.Why put a more expensive spark plug when you cant adjust how much power you want to send to the plug when everything on the truck is computerized.

 

Yep............NGK Iridums in my03 Hemifor over 28,000 miles now. Not one single issue.
They should be good for 100,000 miles, that's why I went the expensive route.
I still pull a couple of plugs and look at them every now and then, just to check etc.
Al.

 

Thanks for the advice, is there a good way to get the back four out. A trick of the trade maybe?