Ruthenium spark plug
- Thread starter Dmflash
- Start date
Matt
Member
- Dec 2, 2011
- 4,039
Probably not. Our trucks seem to favour the Delco 41-103 iridiums for the 4.2.
The acdelco plugs are made by NGK. The design is more than two decades old. Maybe these new ones from the company are improved - I can't imagine them being any worse than the OEM plugs.
The NGK part# is LTR5AHX. I would suggest that if you need plugs, you should try them
And give us a report of the results!
If I didn't change my plugs 2500 miles ago, I would do it.
The NGK part# is LTR5AHX. I would suggest that if you need plugs, you should try them
And give us a report of the results!
If I didn't change my plugs 2500 miles ago, I would do it.
Mooseman
Moderator
This engine is VERY picky about its spark plugs. I'd stay with the Delco 41-103 iridiums or NGK equivalent. As for difference in performance, probably meh. It's like the difference in lighting a BBQ with a match or a lighter. Both will still cook your steak.
Just my 2 cents worth: The iridium plugs last 100,000 miles with zero problems. They are a bit costly, but with their longevity they are worth every penny (provided they aren't bogus knockoff plugs). When I was younger plugs didn't have a chance to last that many miles, so not "worrying" about them for 100k miles is nice. So I thinks: if it ain't broke, don't fix it. And the iridium plugs aren't broke (but subject to making us broke at the cost of them )
Matt
Member
- Dec 2, 2011
- 4,039
Agreed, but they're not that expensive, $8 from Amazon.
The plugs for my SS Commodore back home were $25 each in 2002...I needed 8.
Hmm those may be worth a try, $8 on RockAutoThe acdelco plugs are made by NGK. The design is more than two decades old. Maybe these new ones from the company are improved - I can't imagine them being any worse than the OEM plugs.
The NGK part# is LTR5AHX. I would suggest that if you need plugs, you should try them
And give us a report of the results!
If I didn't change my plugs 2500 miles ago, I would do it.
FitsTrailblazer Base Model; Gap 0.050"
orTrailblazer EXT; Gap 0.044"
Is that correct?
- Jul 22, 2015
- 2,724
I can't imagine the 4.2L uses different gap in SWB vs. LWB. If it did, people could just gap at the EXT spec for "more power". LOL
The 'EXT' spec must be assuming the V8 is present.
Mooseman
Moderator
One of the cheap brands on RA has these gaps, which doesn't make sense. And it's not because of the V8 as it uses another plug part number so I have no idea where this is coming from.
In any case when using Iridium or Ruthenium plugs, the gap should not be adjusted as indicated.
In any case when using Iridium or Ruthenium plugs, the gap should not be adjusted as indicated.
Heed @Mooseman 's warning...
You WILL break the electrode if you attempt to adjust the gap as if it were an ordinary plug. Genuine (because there are counterfeits) Iridium and Ruthenium plugs never need gapping as they are pregapped from the factory and shipped with a plastic or cardboard collar that prevents the gap from closing during shipping. If the gap is closed or the collar looks damaged, return the plug. Iridium and Ruthenium electrodes are extraordinarily brittle and will pretty much shatter like glass if you apply mechanical forces to them.
Gapping can be done on any plugs without touching the electrode with the proper tool. Having said that, it should not be required if the plug was spec'd properly (ie. not "fake3") for the target vehicle.
According to NGK the 90220 LTR5AHX Ruthenium are pregapped to .043" so those should require no adjustment?
This is interesting:
This is interesting:
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Mooseman
Moderator
To gap them, you'd have to put a feeler gauge in there to measure and that is where the risk of breaking them lies. And with those Ruthenuims with skinny electrodes on both, you might get them out of alignment. As @TequilaWarrior said, if the gap or electrodes look off, return it.
