Iridium vs Ruthenium spark plugs

[Popsy]

So, spark plug replacement time for the Mazda (2.3 engine).

On the right, standard iridium that are OE on the car.

Price is identical, actually the Ruthenium are a few cents cheaper, but that's negligible.

Gap is the same, form factor too. I always thought the Laser iridium meant double iridium electrodes, but now that I look closely I can only see one ?
Not sure about the replacement interval, but it's a very long thing like 100k Km.

Ruthenium seem to have two visible pointy electrodes of whatever fancy metal they are advertised.

There is little I can find about Ruthenium spark plugs, except it's the new sliced bread, better, last longer, etc etc.
If the Laser iridium have indeed only one iridium (or platinium + iridium) pointy electrode, I can see the Ruthenium lasting longer.

So, what's your take ? Can you educate me on spark plugs ? On most 4 cylinder they are real easy to replace so I always them as a maintenance item, replace every few years and don't think twice about it.

 

[Astro14]

Ruthenium is a metal. Element 44. It has a slightly higher melting point than iridium. Element 77.

Do they perform better? Last longer?

No idea.

 

[dailydriver]

I have a set of factory heat range Rutheniums for this 1.6 EcoBoost which I have not yet installed.

I will do so right before the summer rally working season to see if my long highway drives to get to these events yield any better mileage (or performance) than the factory Motorcrafts still in the car at this point.

 

[geeman789]

Don't Iridium plugs already last 100 000 miles ? Are we moving to LIFETIME plugs now ?

 

[WobblyElvis]

The dual tip is not necessary for most applications. In a waste spark system the spark jumps the opposite way on every second plug, that why the special tip is needed on those plugs. Over time the spark tends to carry some of the base metal from the plug with it eroding the electrode. These fancy metals prevent that from happening.

 

[Number_35]

Funny, a few weeks ago I bought the same Ruthenium plugs, to replace the Iridium plugs in our '09 Mazda (with the same 2.3 l engine). Per NGK, G-Power Platinum plugs are good for 60K km, Iridium IX 100K km, and Iridium Laser 120K km. Not sure about the Ruthenium HX plugs, as they were not around when I contacted NGK about the longevity of the various grades. Nevertheless, I expect them to last at least as long as the Iridium Laser plugs. My main reason for the upgrade is to eke out that last little bit of fuel economy, and to help prevent undue stress on the coils.

Agreed, on the Mazda 2.3 they're easy to change.

Here's NGK's qualitative description of the Ruthenium plugs:

http://www.ngksparkplugs.ca/products-spark-plugs-Ruthenium HX.cfm

 

[Cujet]

We are getting to the point where plugs fail in other ways, well before the electrodes are worn out. Internal resistor breaks down, insulator cracks or the seal fails.

 

[Popsy]

Agreed. I've seen cracks in insulator, plugs fooled by carbon deposits...well also electrode very worn out, but the plugs probably weren't iridium, more platinium maybe ?

I guess in this Mazda application they are cheap and easy to replace, so why not get the new NGK top of the line ? It won't probably make any difference, but they cost the same

It'd be interesting to see a slight fuel economy improvement, I doubt so with a modern coil on plug ignition system, but why not.

 

[slacktide_bitog]

Iridium is already good for 100k, but the ruthenium is definitely worth it on cars where it's hard to do them on. Almost any transverse V6/V8, 4th gen Camaro/Firebird, Aerostar, Subarus, etc.

For cars where it's easy to do them, no need to waste the extra money on the ruthenium

 

[Popsy]

In my case they are a few cents cheaper than the Laser Iridium

 

[rubberchicken]

Originally Posted by WobblyElvis
The dual tip is not necessary for most applications. In a waste spark system the spark jumps the opposite way on every second plug, that why the special tip is needed on those plugs. Over time the spark tends to carry some of the base metal from the plug with it eroding the electrode. These fancy metals prevent that from happening.

Is that how a waste spark system works ? I always thought it just means that the plug fires twice as often.

 

[oldhp]

Originally Posted by rubberchicken
Originally Posted by WobblyElvis
The dual tip is not necessary for most applications. In a waste spark system the spark jumps the opposite way on every second plug, that why the special tip is needed on those plugs. Over time the spark tends to carry some of the base metal from the plug with it eroding the electrode. These fancy metals prevent that from happening.

Is that how a waste spark system works ? I always thought it just means that the plug fires twice as often.


How can the spark jump backwards? Waste spark is the plugs firing on compression and exhaust stroke. I thought ruthenium was a joke............Guess I ought to check out the spark plug section more.

 

[pbm]

If I had that choice I'd choose the 'Rutheniums'......I dated a girl named Ruth once.....J/K....I like the fact that the precious metal is on both tips and I trust NGK....

PS: Popsy....your pictures are awesome....my (old) eyes can't see my plug tips as clearly as your great pictures show them....Thanks.

 

[das_peikko]

I'm going with NGK double platinum next time. The Iridium plugs have always looked too delicate.

 

[clinebarger]

Originally Posted by oldhp
Originally Posted by rubberchicken
Originally Posted by WobblyElvis
The dual tip is not necessary for most applications. In a waste spark system the spark jumps the opposite way on every second plug, that why the special tip is needed on those plugs. Over time the spark tends to carry some of the base metal from the plug with it eroding the electrode. These fancy metals prevent that from happening.

Is that how a waste spark system works ? I always thought it just means that the plug fires twice as often.


How can the spark jump backwards? Waste spark is the plugs firing on compression and exhaust stroke. I thought ruthenium was a joke............Guess I ought to check out the spark plug section more.

 

[Snagglefoot]

Iridiums last a minimum of 100,000 miles. Rutheniums have only been here a while so I guess we'll have to wait and see. It might take 5 to 10 years for most people to rack that up over 100,000 miles. Once you see Rutheniums show up in vehicles from the factory you'll know they are good stuff.

GM has been running Iridiums in LS engines from the factory for over 10 years.

 

[Popsy]

Originally Posted by pbm
If I had that choice I'd choose the 'Rutheniums'......I dated a girl named Ruth once.....J/K....I like the fact that the precious metal is on both tips and I trust NGK....

PS: Popsy....your pictures are awesome....my (old) eyes can't see my plug tips as clearly as your great pictures show them....Thanks.

We are in the same boat ! I admit while I was taking the picture I wasn't too sure the tips were in focus.
The picture isn't good enough, but it seems there is something at the bottom of the iridium plug...it's supposed to be a platinium disc of some sort. Honestly when I look at the plug in real life I can't see anything.
Originally Posted by das_peikko
I'm going with NGK double platinum next time. The Iridium plugs have always looked too delicate.

Don't they look the same ?
Originally Posted by Snagglefoot
Iridiums last a minimum of 100,000 miles. Rutheniums have only been here a while so I guess we'll have to wait and see. It might take 5 to 10 years for most people to rack that up over 100,000 miles. Once you see Rutheniums show up in vehicles from the factory you'll know they are good stuff.

That was also part of my thinking. How recent are the Ruthenium plugs ?

 

[nthach]

Originally Posted by das_peikko
I'm going with NGK double platinum next time. The Iridium plugs have always looked too delicate.

Toyota has been running Ir-tipped plugs since the late 1990s. GM has been running them for a good while as well.

 

[Snagglefoot]

Quote



That was also part of my thinking. How recent are the Ruthenium plugs ?


NGK announced Iridium plugs in 1994. My 2008 LS engine had a set of AC Delco Iridiums from the factory. NGK then released Ruthenium plugs at the 2018 SEMA convention.

 

[Snagglefoot]

On the left is an AC Delco Iridium plug with 180,000 miles on it. On the right is a new AC Delco Iridium plug. If Ruthenium is more resistant to erosion, that would be interesting.