Spark Plugs

[CapitalTruck]

Man, don't go to the dealer for a part like this. There are many parts stores that can give you the exact ACDelco part for much less. I was quoted 8.00 or so per plug for the iridiums. Very same ACDelco part number and everything. Shop around a little bit, 20.00 is way too much. I have 70,000 on my truck, I took the plugs out and put them back in just to keep them from fusing too the block. It still runs fine so I don't feel the need to replace yet. One issue, how do you all get the right furthest rear plug out? I couldn't get a socket in there w/wrench to save my life. Maybe a universal joint is necessary?

 

 

OEM Irridiums are 20 bucks a hole for my 02 Tahoe 5.3L from a recent parts quote from several dealers. I've got 160,000K on the originals and the truck still runs like a top but I think I will change them out before winter as preventative maintenance. Guess thats why they are pricey.

[jblakeney]

Sup group. I am a NAPA Jobber owner. As Per, my ACDelco suppler-tech school. The ACDelco Platnium & Iridium Spark Plugs are built by NGK. The Delco plugs are the correct plugs. Most of the trucks with the 5.3 6.0 8.1 came with 41-985 ACDelco plugs. If the truck came from canada put the 41-985 plugs in the truck or a 7164 Iridium NGK. Walk in my store for the ACDelco 7.36 vs NGK 8.26! The 2 plugs are near the same in appearance the heat ranges are the same. A Rapid Fire ACDelco is not the OE PLUG this plugs will run approx. 20k and require replacement again, as they are not designed for the 100k voltage that DIS produces.

 

Jeremy

[smbsierra]

I switched from the stock (I assume) AC Delco plugs when I bought my truck (used about 2 years ago) to the Bosche Plat +4 and at first noticed little or no difference. Now, about 12K miles later, I have a roughish idle and my check engine light is on. I had it scanned by my local shop and was told that it was the sparkplugs triggering the code. Not only that, they said that they see that quite often in the GMC/Chevrolet platform when switched to a non-OEM plug. This weekend I'm going back to the ACDelco Iridium (41985 at my local Advanced Auto) and then I'll have the light reset and hope that was it.

[silversport]

What about the two sets of (now no longer made) AC/Rapidfire Platinums I have???...My Corvette came with GM supplied Platinum 'Denso's (formerly Nippondenso)...sure about the NGK or are they using them too???

 

Bill

[ws6_guy]

I'm gonna replace my stock plugs & wires with NGKs & Taylor wires when the time comes, 35,000 miles I should need to do this until 75,000 - 100,000 right?

[silversport]

...using the AC Delco RapidFires (#12) in my OBS Escalade (5.7 liter/350ci)...mine are the newer RapidFire Platinums...

Bill

[WFO]

IMO Go cheap and change more often.

[carl425]

How about Pulstar, anyone tried them? At $25/piece (sparkplugs.com price, I'm sure they can be found cheaper...) they should be something amazing... Check out this pseudo-independent dyno test http://www.sparkplugs.com/sparkplug411.asp...ults&mfid=0 . If this was done right and they really gained 3HP from plugs alone, I'm impressed.

 

I still don't see me shelling out $200 for plugs EVER.

[crazymex88]

So when should you replace the stock spark plugs from your truck? When I bought my truck, they told me from 80,000-100,000 I should do a tune-up.... Is this correct, or should I do it sooner.

[Doomsday]

I voted NGK, but I also really like Denso plugs as well.. I run the same stuff in all my rides so my performance vehicles get Royal purple and denso's/ngk's. Wires arent a big deal anymore none of my vehicles have them. Well the chevy has some but there about 1.5"s long so I'm not worried about it.

[Gray Ghost]

 

 

I had NGK Iridium TRI55 in GTO

 

I put E3 plugs in the sierra.. She runs great!!!

[jbone22]

How about a review on the E3's ? Are they up to the claims such as more horsepower, better MPG, etc.

[txab]

'04 Sierra 5.3 T

 

What is the opinion on Autolite XP Finewire Iridium plugs? Also Autolite Professional wire sets? Anybody using Denso?

 

I can find the Auto XPs for $2 right now.

 

Comments anyone? Everyone?

[zaac]

I have never changed plugs yet, on my 99 GMC Z-71. Though I did checked them last week and they looked great. My truck runs better than my L48 vette did.(77) Current mileage is 258k km and I bought it at 160k km. 5 years ago. It's been a great truck and I don't baby it, but I don't abuse it either.

schmuly

Thats too weird. I changed my original plugs at 180k kms and they were in bad shape. Truck still ran good though. I have the Delphi ignition system, what do you have? Maybe that's the difference. I can't remember what the other ignition system was called.

[zz50]

I have 210km on my 2003 5.3 and no issues. The OE plug is AC Delco irridium. I will replace with the same since I bought them 6 months ago and found my plugs are still OK. I think the ACD are made by Denso since I don't believe they have the technology to make their own. ACD number is 41-985 or GM 12571164 Gap is .044" (1.1mm). These stories of more power and incresed fuel mileage are bogus marketing gimmicks with todays' ignition systems. Today's systems will fire anything to 1/8" gap and more so misfire is a thing of the past. So if you don't have misfire what is a plug change going to do? Just another way for the masked marketers to separate you from your $$$.

 

I have never changed plugs yet, on my 99 GMC Z-71. Though I did checked them last week and they looked great. My truck runs better than my L48 vette did.(77) Current mileage is 258k km and I bought it at 160k km. 5 years ago. It's been a great truck and I don't baby it, but I don't abuse it either.

schmuly

Thats too weird. I changed my original plugs at 180k kms and they were in bad shape. Truck still ran good though. I have the Delphi ignition system, what do you have? Maybe that's the difference. I can't remember what the other ignition system was called.