Change Spark Pugs at 70,000 Vs recommended 100,000 Miles

[Zoe Saldana]

I'd wager a new PCV valve had the major impact. We experienced major losses of power on engines with restricted PCV's at work (these from icing in adverse weather test conditions).

Engine Masters ran dyno tests on all types of spark plugs, worn, new, etc., and saw little difference in output. In other words, unless the combustible mixture isn't burning thoroughly, there's not much difference. So why change spark plugs? Because we don't know exactly when they will become that worn. That's why we change at different intervals to see when the electrodes start to erode and arc-flash over. But it may become more difficult to pull the wiring boot and unscrew the plug if we wait too long. I had a helluva time pulling plug boots on my big block Chevy in my motorhome. Plugs were too close to the exhaust manifold and got thermally welded to the boots!

My experience has been 30 k miles for nickel coating, 50k miles for platinum coating, 100k miles for iridium coating, who-knows-what for ruthenium coating.

My understanding is that the 2500 6.4L has an internal PCV or something - that can not be changed. I just looked on my 6.4L and I don't see one.

Is there a PCV that can be changed? If so where is it?

Thanks

 

[HEMIMANN]

My understanding is that the 2500 6.4L has an internal PCV or something - that can not be changed. I just looked on my 6.4L and I don't see one.

Is there a PCV that can be changed? If so where is it?

Thanks

Correct. It was not intended to be changed according to MOPAR service (told me), but as we all know, there's no such thing as "built for life" haha. I've discussed this with Nick @ got exhaust and he confirmed. I think this one requires pulling the intake manifold as well, I'm not sure. Anyway, I kind of forgot about it.

 

[Zoe Saldana]

Correct. It was not intended to be changed according to MOPAR service (told me), but as we all know, there's no such thing as "built for life" haha. I've discussed this with Nick @ got exhaust and he confirmed. I think this one requires pulling the intake manifold as well, I'm not sure. Anyway, I kind of forgot about it.

Taking the manifold off is too much for me. I'll forget it also.

 

[HEMIMANN]

Taking the manifold off is too much for me. I'll forget it also.

Ask @[email protected] I don't know where his user name went. He knows all about this.

 

[4xdad]

Changed the plugs on my buddies 2011 5.7 what a pain don’t do it until you have to 2 plugs per cylinder and some are a real pain to get at

 

[DILLIGAF]

Changed the plugs on my buddies 2011 5.7 what a pain don’t do it until you have to 2 plugs per cylinder and some are a real pain to get at

Its super easy to do plugs on these trucks. just go thru the wheel well. literally only take 2 minutes to pull them off and you get full access...

 

[Zoe Saldana]

Its super easy to do plugs on these trucks. just go thru the wheel well. literally only take 2 minutes to pull them off and you get full access... View attachment 481576View attachment 481577

Those plugs look pretty good from here.

 

[DILLIGAF]

Those plugs look pretty good from here.

I change them out every 2 years. regardless of mileage. Its 30$ for 16 Champion 446 at RockAuto.

 

[4xdad]

If we had of known that’s what we would have done lol thanks for the tip

 

[HEMIMANN]

I change them out every 2 years. regardless of mileage. Its 30$ for 16 Champion 446 at RockAuto.

Your manual say 30k or 100+k miles?

 

[crash68]

Ask @[email protected] I don't know where his user name went. He knows all about this.

you mean this username: @Nick@GotExhaust

 

[DILLIGAF]

Your manual say 30k or 100+k miles?

Manual ? I like keeping my Vehicles as long as possible so I would never follow them.

That manual says to use 5w20 lol....

 

[scott lass 18]

change mine at 50,000 cuz had a bad injector , coil and is had another misfire no 1 so change some plugs did some had shop do rear ones too had to get at for me . it seems to start better faster when turn the key and did a new battery it went bad so after years felt it just needed it all done . start right up at 30 out side and runs fine now ! hope lifters hang in there !

 

[huntergreen]

I'd wager a new PCV valve had the major impact. We experienced major losses of power on engines with restricted PCV's at work (these from icing in adverse weather test conditions).

Engine Masters ran dyno tests on all types of spark plugs, worn, new, etc., and saw little difference in output. In other words, unless the combustible mixture isn't burning thoroughly, there's not much difference. So why change spark plugs? Because we don't know exactly when they will become that worn. That's why we change at different intervals to see when the electrodes start to erode and arc-flash over. But it may become more difficult to pull the wiring boot and unscrew the plug if we wait too long. I had a helluva time pulling plug boots on my big block Chevy in my motorhome. Plugs were too close to the exhaust manifold and got thermally welded to the boots!

My experience has been 30 k miles for nickel coating, 50k miles for platinum coating, 100k miles for iridium coating, who-knows-what for ruthenium coating.

How often should the pcv be changed ? Thanks

 

[DILLIGAF]

How often should the pcv be changed ? Thanks

Pull it and check it is the best option. I changed mine out after 4 years the first time.

I can also confirm that the STANDARD MOTOR PRODUCTS V470 is the exact same as the OEM mopar one as it even has the mopar logo on it... lol...

 

[huntergreen]

Pull it and check it is the best option. I changed mine out after 4 years the first time.

Thanks dillgaff

 

[Sherman Bird]

I've read many posts that people have changed their spark plugs at 100K and the plugs still look good.

I have 70K miles and looking to do all the maintenance I can. Will I see any benefits to changing the plugs now vs 100K?

Thanks

Many well meaning responses here.... That said, take the vehicle to a trusted shop that has a high end scanner where they can look into Mode6 data in hexidecimal computer control monitor, and see if there are any events of misfires shown there. This will occur LONG before you'd ever get a check engine light or any hard misfire(s). TID 56 is Ford's and GM's. FCA might be different, but continuous misfire monitor is required under OBD2 protocol.

This is THE accurate way to see IF you need to change the plugs early. E.G., I have recently run across a few vehicles with no check engine light on, but in doing diligence to my customers, I'll run mode6 diags when the vehicle is in for other services. Catching problems BEFORE there is a big issue really serves to save the customer big money later.

 

[HEMIMANN]

Many well meaning responses here.... That said, take the vehicle to a trusted shop that has a high end scanner where they can look into Mode6 data in hexidecimal computer control monitor, and see if there are any events of misfires shown there. This will occur LONG before you'd ever get a check engine light or any hard misfire(s). TID 56 is Ford's and GM's. FCA might be different, but continuous misfire monitor is required under OBD2 protocol.

This is THE accurate way to see IF you need to change the plugs early. E.G., I have recently run across a few vehicles with no check engine light on, but in doing diligence to my customers, I'll run mode6 diags when the vehicle is in for other services. Catching problems BEFORE there is a big issue really serves to save the customer big money later.

Wow, that's useful info, thank you.

I think it would be useful though to know the approximate "L10" life when this would occur with iridium coated spark plugs instead of random, occasional checks, though? At what mileage should an owner start checking or change knowing the average lifespan mileage has been reached?

Remember the old spark testers where you had to take out the plug and put it into the machine?

 

[Sherman Bird]

Wow, that's useful info, thank you.

I think it would be useful though to know the approximate "L10" life when this would occur with iridium coated spark plugs instead of random, occasional checks, though? At what mileage should an owner start checking or change knowing the average lifespan mileage has been reached?

Remember the old spark testers where you had to take out the plug and put it into the machine?

Iridium plugs are supposedly good for the life of the vehicle. Good theory, but not practical in the real world. Plugs will leak past the ceramic to either the outer shell or the inner electrode. 100K miles should be plenty often enough, but, there again, I live in Houston, Texas.... where the freeways are rife with Indy 500 wannabees!

Looking at TID (Test Identification) 56 in mode6 will show events of misfire across the board. My 2004 Ranger shows 22.000 and change.... not enough to flag misfire codes in the PCM to set a code or illuminate the Check Engine light. It's enough of a concern that I will chase down the cause so as NOT to burn out the MOSFET transistors in the PCM (it's a waste spark system). I suspect the cam sensor, mounted on top of the oil pump drive (was a distributor on early renditions of this engine) is not in perfect phase to the crank sensor. It will eventually flag a P0300 "random misfire" code if left unattended. That, in turn will kill the catalytic converters over time.

 

[HEMIMANN]

Sure glad they upgrade the waste spark system on 1st Gen III Hemis to normal direct spark! I had the waste spark on my 2012 with the 30,000 mile change interval with copper/nickel electrodes only. Wasn't too happy they were too cheap to put on enough coil to fire both with resistive coatings. Ah, well - all is well now with my factory dual iridium's (NGK for Mopar).