Glow plugs. One or all?

[spock123]

I have a 2012 Silverado 3500 that use to eat glow plugs, now I haven’t had one go bad in over a year. All the glow plugs have been changed under warranty, some twice. Since I deleted the emissions none of the glow plugs have gone bad. The shop that did the delete said not worry if a glow plug went bad, I live in North Carolina

[dodgemark]

Originally Posted by BriaBeck

I'd just replace the defective one... the others may still have a lot of life in them yet.


Even though changing them is like changing a spark plug, they are not spark plugs, and they don't operate like spark plugs or perform the same job as a spark plug.


Ultimately, it's up to you though, and it's your money. They're not cheap.

There like 10 bucks a piece. If one goes bad, others may be close behind. Change them all. Make sure you check connections they can go bad too

[timfromma]

Originally Posted by kbrown1075

I am very detailed about my vehicle maint. Now I live in the south and not a cold environment. I have owned my truck for 6 years, 162,000 miles, and have had one glow plug go out. I purchased the replacement on line and changed it myself, very easily. That was about 3 years ago and 35,000 miles ago. If one fails, I'll replace the failed device. I have been in electronics for many, many years, stuff breaks, but not all stuffs. You'd replace your whole entertainment system because the DVD player stopped working? One glow plug might go out every three years (or more), why would I replace all of them for a defective one? Just my choice.

Glow plugs have a limited life span, like headlights. When one goes out, the others are probably not far behind.

[mrfikser]

All the above is good advice, I would only add that I would compare the electrical resistance of the new glow plug[s] to the old ..if they are not within about 5% of each other I would replace them all, or at least all that were of a different resistance...I have found that with different years etc. that what looks like an identical GP (and aftermarket) may have a different resistance than original models..The GPs with the lower resistance will glow hotter than the rest and go bad quicker...another reason to change them out as a set..

[timfromma]

Originally Posted by spock123

I have a 2012 Silverado 3500 that use to eat glow plugs, now I haven’t had one go bad in over a year. All the glow plugs have been changed under warranty, some twice. Since I deleted the emissions none of the glow plugs have gone bad. The shop that did the delete said not worry if a glow plug went bad, I live in North Carolina

One annoying side effect of a bad glow plug is that the check engine light comes on which disables the remote start.

[spock123]

I can clear the code for the glow plug but it will pop back on later

[kbrown1075]

Originally Posted by timfromma

Glow plugs have a limited life span, like headlights. When one goes out, the others are probably not far behind.

But I don't replace both headlights when one goes out. If I were to change out all the GPs when one goes bad, that means if one goes bad after replacing them 35,000 mile ago, I need to replace them all? Not economical in my opinion. As I stated in my OC, I have gone 35,000 mile (3 years) after replacing just one bad glow plug, and I'm still chugging along. They are cheap enough, and accessible enough to change as they go, IMO. Kind of like changing the fuel filter when doing an oil change. I've gotten bad fuel and needed to change the fuel filter with 80% filter life remaining. An oil change may be 3,000 miles away. At the time of the oil change, I'm not going to replace a fuel filter with 60% life in it.

We all have our looks at this kind of stuff, and we just have to do what we feel works for each of us. Happy travels!

[timfromma]

Originally Posted by kbrown1075

But I don't replace both headlights when one goes out.

It's recommended that you do. That's why headlights are sold in pairs.

[dodgemark]

Originally Posted by timfromma

It's recommended that you do. That's why headlights are sold in pairs.

Exactly. Especially when it comes to glow plugs. Why keep changing them one at a time. If one goes, the others are not far behind. Go in motor once and be done, for the price of them it just makes since to do all.