I have a 2012 Durango with the 3.6L V6 and it has about 192,000 Kms (120,000 miles) on what I believe to be the original spark plugs. I am not experiencing any obvious problems with performance, but that seems a lot of mileage on the original plugs. Apparently that model uses iridium plugs which are noted for their longevity.
Since we are snowbirds and drive about 3,100 Kms (2,200 miles) one way to our winter home, I really wouldn't want to have them fail one the way there, but at 2 and a quarter hours labour, and $27 per plug I don't want to do it if isn't required. Any advise from you pros.

 

I'm old. (Ugly too but that isn't germane to this.) I replace my plugs every 30,000 to 50,000 miles. The steel shank can weld itself over time to the aluminum head.A light film of oil or anti-seize when I put them in. Then again, I remember replacing them, along with points and condensor every 6 months. With as many miles as you engine has, I'd have a shop do it so you don't pull the threads out of your cylinder head and if they do, they can put a helicoil in.

 

Check the maintenance schedule in your owner's manual. My 2013 manual states 180,000 Km (100,000 Miles) for the 3.6L V6, and 48,000 Km (30,000 miles) for the 5.7L V8 Hemi. And yes, apply anti-seize compound on the threads.

 

Now that's a novel idea, I guess that falls into the saying "when all else fails, read the manual" OOPS, guess I'm due.

 

Not sure where you are getting the plugs or if that is a Canadian price but on rock auto they are $4.61 a piece for Champion Iridium plugs .

 

That was the price quoted at the mom and pop shop that I use to for oil changes. I plan to check with my dealer tomorrow, we have had company most of last week. FWIW, we drove about 400 miles over the past 4 days and the Durango is still working fine. Also, I have no intention of doing this myself, those days are way behind me.

 

Ive talked to some mechanics who say Iridiums being so hard as a material will go 150K without an issue but always go by the manufacturers specs . They give those numbers so you don't get stranded . I know im going to have to get our minivan with the 3.6 liter done soon too as we near the 100K mark . Also usually tranny service is also due around that time so check that too .

 

As an update, the SUV went into the shop this morning, the plugs were extracted and replaced without any problems, the old plugs showed some sign of wear, but the technician said they were in no danger of failing and leaving us on the side of the road. Having said that, and whether it was my imagination or not, the car ran much smoother on the 45 minute drive home.

 

Yeah just had the plugs done on our 3.6 minivan and new Champion Iridiums went in , My place lets me bring the plugs so it was $4.61 a piece for plugs on Rock auto . Yeah the van seems smoother and more responsive now . Not as buzzy vibration wise .

 

OK, I took the Citadel on a trip last week end, and 2 strange things were evident, one is not related to the spark plugs, but one may well be. When the vehicle is not fully warmed, there is a definite shutter at low revs that diminishes but doesn't fully disappear once it has reach full temp. It is the 3.6 motor and I am wondering if others may have had a similar problem? The other issue that I will have checked this week is that at highway speeds the vehicle is very sensitive to all road imperfections, so it has a tendency to wander and gives a rough ride. My guess is that the shocks, or what ever they are now called, need replacing. Any thoughts?