2003 Sierra Plug Change - 69,000 Miles?

[Mr_Joe]

I'm doing some Summer preventive maintenance on our truck. It's been lightly used the last few years but driven more now that we dropped to two vehicles. In the next few days I plan a coolant flush/change with hose replacements.

I was thinking about the plug issue & see the current recommendation is AC-DELCO 41-110 iridium plugs for the 6.0 liter gas engine. The original plugs have not been out or inspected. A relative had a low mileage truck years back where the plug broke upon removal(attempted), it had been in place many years.

The truck is running fine, but I was thinking maybe it's due after 8+ years. I think if I put the 41-110's in I'd be good for a long time?

 

[chubbs1]

Go for it, you are got your money's worth and you will have to do it sometime (unless you plan on selling it).

 

[hattaresguy]

Some GM motors seem to go forever on plugs, I wouldn't touch them until you get a skip. That motor might go to the junkyard on the originals.

 

[beast3300]

I would replace them with the updated plug if it was me. The iridium Delco's are made by NGK and are superb. They will last at least another 70k.

 

[Chris142]

My gf's 5.3L started running funky @ exactly 100K on the original plugs. I put new ones in and they fixed it.

The old plugs looked fine.

Have fun getting to the ones on the passenger side head near the rear. There is a heat shield back there thats got sharp edges.

 

[daves87rs]

Originally Posted By: chubbs1
Go for it, you are got your money's worth and you will have to do it sometime (unless you plan on selling it).


+1

 

[EricF]

whatever you decide to do, stick with the AC Delco's.. albeit I believe Denso makes them instead of NGK..

 

[Mr_Joe]

I have a few days off & I may as well do it. I did hear one or 2 may be hard to get at. I'll keep an eye out for that pax side rear plug. How helpful is one of those jointed extensions for the socket wrench? If it's even helpful at all? I see them mentioned at times.

According to a web search the local Autozone has the plugs in stock. Since I don't want a plug someone messed with(factory gapped) I may go with them over an e-bay deal.

 

[sandy_d]

Originally Posted By: Mr_Joe


According to a web search the local Autozone has the plugs in stock. Since I don't want a plug someone messed with(factory gapped) I may go with them over an e-bay deal.


Good point, FleaBay is a real gamble when buying ANYTHING unless it is a legit store doing business as an outlet, I never buy anything on there.

 

[mechtech2]

Sure - put those great new plugs in!

And I don't recommend any flushing . Just drain and fill.
Unless you have a specific need or problem, don't flush.

 

[FZ1]

It ain't the miles:It's the miles and the years. 6 years max change interval for me.

 

[Jim Spahr]

Does the 6.0L have alum or iron cyl. heads? If alum.heads, I would say def. change the plugs. If iron heads, although not as urgent, I would change the plugs to the rec. Delco plugs and use anti seize.

 

[Mr_Joe]

Today I planned to take a plug out to look at. For the life of me I can't get the boot off. It's tighter than anything. Now I'm looking at that Schley 'boot puller', or one of the others, any advice?

I was just going to look at one plug, & the 2 easier ones I tried I can't get the boot off - pulling rather hard too.

I still plan my anti-freeze fluid change, mostly drain & refill. I think I'll do the plugs also, just need to get the plug wires off.

 

[Mr_Joe]

I did get the one out, it was worn but still not to bad. The gap was up to .o55 with the center showing some wear. As mentioned elsewhere, I don't feel like putting them back in after the effort expended. I plan to get some plugs tonight, $6.99 Autozone & tackle them one at a time. With the 41-110 plugs in I think I will be done for as long as I own this truck. I may pick up a 'boot puller' also, if it looks like it will help.

 

[Jim Spahr]

The boot puller will def. help. When you put the nose of the puller on the plug, twist them left and right as you pull ....The rubber boot welds on due to engine heat. Be sure to put a s/p boot dressing on the inside of the boot before you reapply or they will stick again. Permatex makes a tube of boot dressing. Some discount stores sell the dressing in foil packets at the counter. Good Luck.

 

[GMBoy]

Replace the wires when you change the plugs. Age, ozone, heat and all have taken their toll on those wires. Why have new plugs and not get all the fire to them? I changed my 2006 Sierra Denali (6.0 also) plug wires with MSD red wires and Bosch Iridium Fusion plugs at around 45k miles due to a small miss. Now at 66k still running good. No horror storys the Bosch haters spew about check engine lights, misses and all.

 

[Mr_Joe]

The 'boot puller' has been working very well. The boots are still tight & sticky, but at least I can get them off. I did the 4 plugs on the driver side yesterday & will do the other 4 later. I have to leave town for 2 days.

I used anti-seize on the threads & the 'boot grease' with the boot contact. I'll research the wire some, but for now just put the old wires back in place. The old wires looked good & will be easy to change compared to the plugs later.

 

[FL_Rob]

I'm going to spoil the party ,spray wd40 ,aero kriol ,pb blaster .etc, whatever you have.wait a few hours then pull...twist.. yank, that boot off.The worst that can happen is you slide the boot up on the wire.On the topic of extenions,I use whatever combination of u-joints, extentions ,wobble joints /hands tightening as I can get.No fear, as long as you hand start first.Next,Getting the plugs out ...all bets are off.As for your relative? You have Iron heads, not aluminium( yes the british tense)should take the strain of removal of said threads,and do it cool,you can spray the spray all up in there at the same time ,dont be shy.Goose it..

 

[Mr_Joe]

Just FYI, the plug change is complete, the new iridiums are in. The key was the boot puller pliers I borrowed from a guy. I used the anti-seize & 'boot grease' for the new plugs. Even that rear plug on the passenger side went fine with the boot pulling pliers. These may be it for as long as I own the truck.

I also changed the upper & lower radiator hoses & the coolant fluid. That was partially to remove an inline heater.