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Spark Plugs

T

TonyAngel

Full Member
Joined
Oct 27, 2015
Messages
51
Location
New Orleans
Hey all,

I can't believe I'm tearing my hair out over something as simple as spark plugs, but...

I'm getting terrible mileage and the idle is a little rough on my 2004 Avy with 5.3.  The guy that had it before me only used the truck for short trips so I'm figuring that a spark plug change will likely help, although I only have 57k miles on it.

I've combed through the forums and am still confused as to whether I should get platinum or iridium plugs.  Whenever I go to a parts site and search for parts by vehicle, I'm told that my application calls for platinum plugs, but many here are saying that they are getting good results with iridium.

I found this...
http://www.acdelcotechconnect.com/pdf/tsb/tsb_03D-J-171.pdf ...which led me to think that iridium was the way to go, but then, I saw this,

http://acdelcoadvantage.saepio.com/LWServlet/prod_data/originals/assets/Weekly+Update+Attachments/5+May+2013/13D-070.pdf and am now thoroughly confused.  From what I understand, they went back to platinum because peeps were complaining of degraded gas mileage.

So...what is it that I'm "supposed" to be using in my '04 Avy?

Thanks.
 
long ago it use to bethe old type plugs, but now GM recommends iridium in all trucks.
 
Look plugs up on rocket.com and get the AC Delco iridium plugs.  Can't go wrong.
 
The second link is correct they are phasing out the iridium plugs, so if you can find them buy a set or 2.

They also changed the gap from .60 to .45
 
MS03, ok. Appreciate that.  My knee jerk was to go with iridium, but was concerned about the number of complaints I've read about regarding bad mileage with iridium.

Your comment indicates that the iridium are indeed better regardless of the bulletin.
 
I used to have an '03 and I ran the Iridium plugs with updated Taylor wires ..  I got the NGK's ...  tr5ix's ...  

I got my plugs from sparkplugs.com

John
 
Working in a car parts store, I cannot tell you how people go "on the cheap" when it comes to replacement parts; brakes primarily but spark plugs are no exception.  I always suggest going with OEM, but...some people.  :E:

My Owners manual states AC Delco 41-985.  I may have to look into a TSB for my 2008.
 
2013 tsb says acdelco 41-110 for 07 and up. I think it's just a new part number for the 985. I just got a set of 41-110 for my '04. Tried to install them, but wires wouldn't budge. After the time I had changing the oil, I thought I'd better wait until I can work in the day light for the plugs. I suppose it should have been expected. They've been in there since 04.
 
As I mentioned, the oil change was a real PITA. Jiffy put the filter on TIGHT. I broke a plastic end cap wrench and the strap type wrench slipped when trying to loosen it. I wound up using a pipe wrench and a good bit of muscle getting it off. Tore it all to hell. Oil all over the place.

I went with Mobil 1 extended performance synthetic oil and filter.

For the plug wires I just used a pair of long needle nose with a 90 angle at the tip to grab the heat shields. Giggle and pull. I went with 41-110 iridiums.
 
TonyAngel said:
...I went with Mobil 1 extended performance synthetic oil and filter.

...I went with 41-110 iridiums.
Click to expand...

This is plan for this 08 Avy in the not-so-distant future...plus the Mobil 1 filter  (y)
 
According to Mobil 1, that combo is supposed to go 15,000 miles. I'm curious to see when my change oil light comes on.
 
TonyAngel said:
According to Mobil 1, that combo is supposed to go 15,000 miles. I'm curious to see when my change oil light comes on.
Click to expand...
Oil light does not know what type of oil you use.
 
I understand that, but it's also my understanding that the change oil message is something more than just a "dummy light."
 
Think of it as a reminder to change the oil and please please do not try to get 15,000 miles without a oil change no matter what Mobil1 website says.
 
Yeah, I wasn't planning to.  Synth oil at Walmart is cheap and the act of changing the oil is pretty easy on the Avy.  I'm a small guy and don't even need to jack the truck up.  When I did the last one, it would have taken no more than 15 minutes or so, but for the fact that the butthead at Speedy must have used some sort of impact driver on the oil filter when he put it on.
 
If you want to make oil changes easier, use a K&N HP filter. They have a 1 inch nut on the bottom, just use a 6 point socket with a long extension, makes it real easy to reach up there to take the old one off and to tighten the new one.
 

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