So what plugs should I put in my '04 3.7L?

This thread was quite confusing. Advance Auto suggested the bosch platinums. They were kind of expensive. They're still in the box so let me know guys. I can always return them.

Relevant mods consist of: flomaster 50 series exhaust & soon to be air intake

 

Well im not sure about the 3.7 but I know the 3.9,5.2,5.9 love the autolites 3922

 

Re: Bosch Platinums- IMO, return 'em & get your $ back. I've had too much trouble from Bosch plugs over the years(more than 35 years!) and will *not* put 'em in anything. Safest bet is to use whatever Champion the factory recommends- it should be printed on a sticker under your truck's hood. Bet they'll be a lot less $$ than those Bosch Plats too!

My truck is an 02 3.9 V6, different plug than your 3.7. Previous owner put something else in it, but I'll soon put a set of NGK V-Power copper cores in it. And it'll probably never see anything but those or the OEM rec'd Champions(parts store only had 4 of the correct Champions when I bought the NGKs!) for as long as I own it.

 

I returned the Bosch Platinums. I have both the NGK V-Powers (that actually matched the sticker under my hood [zfr6f-11g]) and I picked up the autolite ap3923s that the walmart computer suggested.

The autolites are a bit cheaper than the NGKs, but I decided to pick up both until i could decide which to use. Then I'll return whatever I don't use.

So, Which is it people?

 

4.7 best on autolites

 

Magnum motors love the 3923's. The ngk's are supposed to be pretty good but I havent tried them in my truck.

 

I used Autolite 5224's in my 4.7 and they worked great. A definite increase in power and gas milage over the old worn out ones...

The 5224 is the same heat range as the OEM plug.

 

I have no personal experience with the Autolites, & would install the NGKs if it were my truck. But since so many others do well with the Autolites, I doubt you could go wrong with either one.

 

I decided to go with the NGKs because they were the exact code mentioned on the sticker under my hood. I'm glad I did because when I pulled the old plugs out (they had at least been in there since before I got the truck at 50,000 and I'm now at 120,000), NGKs were already in there.

Thanks for the help guys. I chose to go with what the manufacture recommended and it is so far real nice. I also installed my intake at the same time. So I will fill up and see what kind of mileage difference I'm getting.