Plugs and Wires for the 5.3L

[RedEnvoyDenali]

I have read several threads regarding only using AC Delco 41-110 spark plugs in the I-6 motor. Since I have 115000km on my 5.3L and will start gathering parts to replace plugs, and wires before next spring I would like to know which plugs are recommended for my Denali. I have read that the 41-985 is a direct replacement for the 41-110, any truth to the rumor?

Second question does anyone have and preferences for Aftermarket or OEM replacement spark plug wires?

Thanking everyone in advance.

 

[jrSS]

Why would u change??? Does ur engine have any mods??

 

[Wooluf1952]

I have read several threads regarding only using AC Delco 41-110 spark plugs in the I-6 motor. Since I have 115000km on my 5.3L and will start gathering parts to replace plugs, and wires before next spring I would like to know which plugs are recommended for my Denali. I have read that the 41-985 is a direct replacement for the 41-110, any truth to the rumor?

Second question does anyone have and preferences for Aftermarket or OEM replacement spark plug wires?

Thanking everyone in advance.

The recommended plug for the 4.2 I6 is actually 41-103

 

[RedEnvoyDenali]

Why would u change??? Does ur engine have any mods??

No mods except for an SS engine cover ( I like the looks). I believe in preventive maintenance. Due for a change at 160000 km but going on 7 years old. For the money I would rather not take any chances.

The recommended plug for the 4.2 I6 is actually 41-103

See what I mean there is definitely a lot of misunderstanding out there. I did not know it was a 41-103 for the I-6thought I had read they were 41-110's . I have since found out that the 41-110 is a replacement for the 41-985.

Any recommendations for brands of replacement plug wires?

 

[C-ya]

Hmmm.... The Haynes manual (24072, 2011 copyright) shows the '04 and up I6's use the 41-981, and the V8's use the 41-985.

 

[TollKeeper]

I just did a tune up on my 5.3. After looking over the engine, I decided I would let a shop do it. It just did not look very freindly..

7 of the 8 plugs are easy as pie. The 8th plug, the one on the passenger back side is a pain in the ass! The mechanic, and freind of mine, took 30 mins to do the 7 plugs, and another hour to do the 8th plug.

With all the rare metals that GM has been using in their engines, I recomend using only the GM plugs.

 

[Wooluf1952]

Hmmm.... The Haynes manual (24072, 2011 copyright) shows the '04 and up I6's use the 41-981, and the V8's use the 41-985.

In the 2007 and 2008 owners manuals they do call for the 41-985 for the 5.3 and 6.0. However they also call for the 41-103 for the 4.2 I6 and that is the AC Iridium.

Not saying Haynes is a bad manual, but I trust the owners manual and the knowledge on this forum more. YMMV

 

[C-ya]

In the 2007 and 2008 owners manuals they do call for the 41-985 for the 5.3 and 6.0. However they also call for the 41-103 for the 4.2 I6 and that is the AC Iridium.

Not saying Haynes is a bad manual, but I trust the owners manual and the knowledge on this forum more. YMMV

That's why I posted, both for my own edification and the forum's. I didn't go out and look in my owner's manual to see what it called for, just happened to have the shop manual handy. I did d/l the service manuals from Mooseman's link, but I haven't looked in those, either.

 

[OMGTruk]

what did you end up going w/?

I plan on running the PCM4less wires w/ the heat socks and a set of NGK tr6's, maybe the tr55s.

 

[06Envoy]

what did you end up going w/?

I plan on running the PCM4less wires w/ the heat socks and a set of NGK tr6's, maybe the tr55s.

I'm just curious. What made you go with PCM4l wires vs MSD? I can't find specs on their wires.
PCM Wires link here.. With heat socks the price is double that of MSD. I can't figure out why....


Personally, I'm at 156k kms. I'm due for a change anytime. I'm going with;
ACCEL 140043-8 - ACCEL Super Coils
MSD Ignition 32829 - MSD 8.5mm Super Conductor Spark Plug Wire Sets
ACDelco 41-110 - ACDelco Iridium Spark Plugs

 

[jimmyjam]

i use the pcm4less wires because they clear headers better the stock-style, straight boot wires. if you are running regular manifolds, no real reason to run them or heat socks

why are you looking at changing your coil packs? i would not change them out unless one failed, and if they did i'd look for stock replacements, aftermarket coils are nothing but trouble

 

[06Envoy]

i use the pcm4less wires because they clear headers better the stock-style, straight boot wires. if you are running regular manifolds, no real reason to run them or heat socks

why are you looking at changing your coil packs? i would not change them out unless one failed, and if they did i'd look for stock replacements, aftermarket coils are nothing but trouble

Aw! That explains the PCM4l wires. Thanks! I am still dreaming about getting the Stainless Works LT headers and true dual exhast with x-pipe, but I seem to have spent my Envoy header $$ on Polaris Ranger mods instead. When I do eventually get my headers, then I now know where to get proper fitting wires from. Thanks again for that explaination!

As for the coil packs, my OEMs are fine but upgrading is better?
In my previous truck, I ran a Vortec 5.7 with all MSD ignition. Coil, wires, Digital 6al, everything. So I assumed that the 5.3l would need to be upgraded as well?
Unfortunately MSD doesn't sell replacment coil packs for the 5.3l. Oh wait! Is that because the truck doesn't need them? Is that what your saying?

 

[jimmyjam]

just do some searching on ls1tech or tbssowners about msd coil packs. the general consensus is that they are expensive and cause problems

 

[am-radio]

Reviving an old thread here. I have the 5.3 also and I'm almost due for plugs. I'm going to use AC Delco 41-110 as everyone recommends. From what I've read though, if you haven't removed the wires in a while, you'll most likely damage them removing them. I might as well buy new and change them also for the price. My truck is stock. The stock AC Delco wires (748RR) are 7 mm and after markets are thicker. What does everyone use or recommend for the 5.3 V8? There are so many, I'd like to run wires that have been "proven" on our trucks.

 

[OMGTruk]

I ended up going w/ the MSD LS1 wires from Fast Motorsports and a set of Denso iridiums because i had a rebate for them that I don't think i recieved. Truck ran smoother instantly w/ 75k miles on it and i've put another 10k since then and its still running good.

I would definately go w/ the AC delco factory plugs again but the MSD's hold up well. I believe my dad's had them on his truck for 100k miles.

on the MSD wires you can re-angle the boots about 20-30* as needed, don't go crazy w/ them but you get the idea.

make sure you lube the plug or you will scrap the nice new wires if you need to pull them again.

 

[jimmyjam]

oems are fine. sparkplug wires are one of those products where purported claims of improvements get blown out of proportion

the only need to consider alternatives is if you have headers, the stock style boot tends to touch a couple of primaries and burn though.

 

[am-radio]

Sounds like OEM is my best bet. Are the 748RR the correct wires? Rockauto shows two AC Delco wire sets for my 5.3 V8