Is there an average life in years or miles that a glow plug lasts? I will be changing injector o-rings and while I'm in there I'm considering changing the glow plugs as preventative maintenance if they're nearing their life span. They've been in there about 4 years. What you all think?

 

I would if it was me. Your going to have it that far apart anyway.

 

My originals were still working fine at 15 years and 300000 miles. I only did them because I had the injectors out too. The wiring harness goes bad more often than the plugs do. I would just test them with a test light while the valve cover is off and only do them is you find bad ones.

 

Wow thats a lot of years and a lot of miles. I plan on tearin the engine down in a couple years for a buildup anyways, so at that point I'd surely change them. Just wanna make sure they ain't known to go bad in 5 years under normal circumstances.

 

I'm not as easy on my equipment as RRanch, LOL. Mine have been in for 6 years and 100,000 miles but I'm starting to start a little harder. I,m going to change mine soon.

 

Yeah I myself have noticed a little longer starting times but not sure if thats because of other issues or if it's as simple as the glow plugs wearin out.