Just in case you end up reading your Owner’s Manual or emissions tag to get the plug gap, GM issued a TSB: Bulletin 03D-J-171 back in December of 2003 that covered 4.8L, 5.3L, 5.7L or 6.0L V-8 engines (VINs V, P, T, Z, G, S, N, U -- RPOs LR4, LM4, LM7, L59, LS1, LS6, LQ9, LQ4 that stated: A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, ACDelco Part Number 41-985 (12571164), is gapped to 1.01mm (0.040 inches) when the spark plug is made. The spark plug gap is set during manufacturing and should not be changed to the gap required with the Platinum plug, or damage to the spark plug may result. (For reference, the original gap with the Platinum tipped plugs was 0.060 inches)

As has already been recommended, if you don’t mind changing plugs on a little more regular maintenance schedule, you can run the regular copper plug NGK-TR55’s. However seeing this is the 1st time you’re changing the plugs unless you purchased it with them never have been changed, you may want to run a plug that has a longer life span, which I would recommend either the factory plugs or the NGK-TR55ix plugs.

 

Damn 200$ , I'm in the wrong business , I could be one rich mother if I could find enough suckers that needed plugs changed .

It's ashame they try to rob people like that .

Also put a dab of never seize on the plug thread , and use about a 5" piece of rubber hose that fits tight over the top of the plug , then use this hose as your handle to get the plug started in the threads correctly , this will prevent cross threading and excessive anger lol , this trick works perfect every time for starting plugs in the head.

And use die electric grease on each end of your wire boots .

There is nothing wrong with MSD wires . The 3 year old set I have have been off and on lots of times and still made 630+ hp to the wheels . Nuff said .

 

I was aware of this, and have read it within the past couple of weeks on a different site. I appreciate the suggestions everyone has posted, this is an extremely helpful forum. This is the first time I have ever changed spark plugs, and as far as the truck goes, I dont know. Ive owned it about 2.5 years, and about to pas 100k miles so I figured it wouldn't hurt to change them. After this, it will be brake pads....yes, I have never done that before either
The whole plug gap is just confusing to me, probably because I'm making it harder than it has to be. I double checked with the dealership and they said it calls for a .040 gap. I will find out what they come in when I order them. I guess I'll go with the TR55ix plugs. Will these be overkill? Will my stock coils even get them hot enough to completely burn fuel in the combustion chamber? Yes, I had more questions

 

The stock coils will run anything from a TR5 to a TR7 plug (and maybe beyond) without issue. The heat range refers to how much heat the plug will store/dissipate during the combustion cycle. Too much heat storage, like a TR4, gets you preignition. Too much dissipation, like a TR7, gets you incomplete burn. The amount of spark power doesn't play into the heat range, however it does play into the gap you're planning to run and the spark plug design. For instance, the stock coils will run single-arc plugs just fine, however when you go to double, triple or quadruple strap plugs the coils will fail to power them.

 

Excellent, thanks for all the help everyone.

 

Does this include the heat sink "truck coils" Suburbazine?

 

Never had any issues with my MSD wires either.... To each his own.

 

for the last plug on the passenger side i foumd it easier to just crawl under the truck and get it from underneath rather than fighting with extensions and swivel heads

 

The round heatsinked coils do put out more power (but still not enough to reliably drive a multiprong plug). The square coils are slightly lower output, lower priced options that I've seen only on non-flex-fuel engines.

 

if this helps with the gapping at all, I asked black bear what he thinks would be best when I did mine and he said he likes 0.045"