Spark Plugs at 44k

[Mike GMC]

They are probably Chinese knock offs.  

[royalkangaroo]

Ones from the local store are much better.




Sent from my iPhone using Tapatalk

[MY164X4]

Looks way better now.

Sent from my SM-N976V using Tapatalk

[royalkangaroo]

Sorry to hijack this thread. I just replaced mine today and put a new set of wires on as well, just for the heck of it. These are mine at 70k miles.




Sent from my iPhone using Tapatalk

[CKNSLS]

19 hours ago, royalkangaroo said:

Sorry to hijack this thread. I just replaced mine today and put a new set of wires on as well, just for the heck of it. These are mine at 70k miles.




Sent from my iPhone using Tapatalk

Those don't look bad at al-IMHO.

[IndyRob K.]

  Has anyone tried the NGK 90220 {#LTR5AHX} Ruthenium HX ?  Im at 86,000 and have some minor shaking during idle so I am gonna do my plugs and wires. I am considering paying the extra cash for these. I remember how well my old truck did when I installed the iridium plugs. Hoping these will benefit my 6.2L with the Ruthenium.  Also anyone go with aftermarket wires?

[Sir Dan]

43 minutes ago, IndyRob K. said:

  Has anyone tried the NGK 90220 {#LTR5AHX} Ruthenium HX ?  Im at 86,000 and have some minor shaking during idle so I am gonna do my plugs and wires. I am considering paying the extra cash for these. I remember how well my old truck did when I installed the iridium plugs. Hoping these will benefit my 6.2L with the Ruthenium.  Also anyone go with aftermarket wires?

At that mileage a rough idle could also be caused by carbon build-up on the intake valves. There are products you can spray into the intake to clean them. 

[IndyRob K.]

1 minute ago, Sir Dan said:

At that mileage a rough idle could also be caused by carbon build-up on the intake valves. There are products you can spray into the intake to clean them. 

Yes I agree. I bought it used last month. The service records showed top cleaning at 60 something thousand. I tried the spray can seafoam but the hose kept getting crushed and not much went in.  I just put on a CAI and I will use a vinyl tube and a funnel and pour liquid seafoam into the throttle body . I did wipe the butterfly when putting the CAI on and it was clean. So I think plugs need to be done asap.

[Sir Dan]

17 hours ago, IndyRob K. said:

Yes I agree. I bought it used last month. The service records showed top cleaning at 60 something thousand. I tried the spray can seafoam but the hose kept getting crushed and not much went in.  I just put on a CAI and I will use a vinyl tube and a funnel and pour liquid seafoam into the throttle body . I did wipe the butterfly when putting the CAI on and it was clean. So I think plugs need to be done asap.

Just FYI, seafoam is a great product but doesn't have the stronger chemicals needed here.  Use Berryman's or a CRC product instead, something with PEA in it. 

[14burrito]

On 11/16/2020 at 5:53 PM, CamGTP said:

Where you live really has nothing to do with heat range temp on the plugs. If you have no power adders and have no need for the electrode to stick out less, don't run anything other than the stock heat range.

Can you please elaborate? 

 

AZ summer heat easily reaches 120F (even hotter at times). Engine heat, soaking, heavy loads, hot air removing heat from hot coolant, ect - this all equates to heat. Hot engine, hot intake temps, just heat in general. Let's not forget the L83 runs on the hot side as it is (210F nominal with a fully open t-stat at 232F).

 

FI generates heat.

 

So how would/could going one heat range down not be beneficial?

 

FI applications utilize colder plugs.

 

Hotter plug, retains heat, high cylinder temps, higher probabilty of pre-ignition and pulled timing.

 

In any case, I installed a setup colder on the L83 and we shall see how she runs over time.

 

I'd still be genuinely curious your thoughts and happy to chit chat via DM if that happens to be easier! Thanks

Edited December 1, 2020 by 14burrito

[IndyRob K.]

6 hours ago, Sir Dan said:

Just FYI, seafoam is a great product but doesn't have the stronger chemicals needed here.  Use Berryman's or a CRC product instead, something with PEA in it. 

I didnt want to turn this into a top cleaning thread.  Im the only one who gets nervous using products with hose adapters and such that with my luck will get sucked into the engine? I love the vinyl tube method for this reason. If I can find the chemicals you stated in a liquid form I would feel much better about switching from seafoam. Thanks again for your advice..

Edited December 1, 2020 by IndyRob K.

[Sir Dan]

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.berrymanproducts.com/products/maintenance/berryman-intake-valve-combustion-cleaner/&ved=2ahUKEwirlrf4pK3tAhXPVzABHQTzBSsQFjABegQIARAB&usg=AOvVaw0FFNs5k8m61RWrCF9T6uFo

This has a nice setup with a curved injection tube.

[ftwhite]

Update:

I now have close to 49k on the truck, or about 5k since the swap. I swapped in NGK plugs (LTR5AHX 90220) and MSD wires (33829). It has been a very nice improvement. Idle and acceleration are smoother. In early Dec, I found the MSD coils (82688) on sale so installed a set of those as well. With that combination all pinging at WOT is gone, and idle is as smooth as I ever recall it being when new. I'd make these changes again, and think waiting until 40-50k+ miles make sense since the improvement seem to get me back to what I recall the new truck felt like (Idle and WOT), rather than better than the original. So it seems some of these parts just wear out sooner than the factory would like to claim. 

 

I also agree with keeping the intake and top end clean. I run Seafoam and CRC through the PCV port next to the TB on my 6.2 every oil change, and this certainly helps with idle smoothness as well. 

[2015 High Miler]

On 11/16/2020 at 2:31 PM, Colossus said:

^^^^^   That is why I tell people to change their plugs wellllll before 100,000 miles.  (Same with coolant and tranny fluid and front and rear diff and transfer case) Just because the manual and GM says they are rated for 100,000+ miles doesn't mean they really are.  But then there are the bone heads who say: "Well... I uh.. have 200,000 miles on the original plugs and never a problem..." 

197,****** same plugs same wires same coils.  
 

signed

 

I have been searching for good replacements for no other reason than I feel guilty.

Edited January 13, 2021 by 15 hi miler

[whistleblower]

 

Glad I found this thread.  Just bought a new-to-me 2020 Yukon XL with 62k miles on the 6.2L.  Previous owner was not mechanically fluent in the slightest and I have no maintenance records outside of verbal "I took it in for an oil change" statements.  

 

Noticed immediately that I have a "rough" idle.  I use "rough" loosely - not a cough/spit/shake about to die rough but a +/- 50-100 rpm change, enough for an observant operator to notice.  Slight shake when idling.  I've seen a couple threads arguing that this is normal on a 6.2L and to just live with it.  I'm wondering if a plug/wire/coil swap would help...?

 

Re: keeping the intake and top end clean - any chance someone has a video on this procedure [quoted below]?  

 

On 1/7/2021 at 1:56 AM, ftwhite said:

I also agree with keeping the intake and top end clean. I run Seafoam and CRC through the PCV port next to the TB on my 6.2 every oil change, and this certainly helps with idle smoothness as well.