My 2009 Hybrid Tahoe is due for routine spark plug replacement since I'm @ 107K miles and I am considering doing it myself because my dealer is delusional with the price they want to charge.

The dealer wants almost $500, 3 hours labor, $10.72 per plug, and 129.06 for the wires, which they insist on replacing not checking.

I can get all 8 plugs online for $42 shipped(PN 12621258 Delco 41-110) and the wires for $67 shipped(PN 19206447 Delco 748UU). I may check the wires and reuse if they pass.

The driver side bank looks like a piece of cake from the top, the passenger side bank is blocked on the top by the DMCM but i'm pretty sure if I remove the wheel/tire and fender liner, I can get to them pretty easily from the bottom with a swivel socket.

Has anyone completed this task?

 

I had mine done by the dealer including changing brake build, tranny fluid, differential and transaxle fluid and radiator fluid.

 

The passenger side rear are NO fun at all. Driver's side relatively easy. Twist at the coil and spark plug ends to avoid tearing the wires. That is if you intend to re-use the wires.

3 hours labor is delusional. At least one On-Line labor guide says 1.5 hours labor. That's about right.

 

I had my trasmission fluid, differential fluid, engine coolant & DMCM coolant(A separate system) changed, this dealer was very reasonable for these items.

Shockingly my brakes still have over 50% left @ 107K miles.

If they would charge me a reasonable 1.5 hours labor and discount the parts slightly, I would just have them change the spark plugs becuase it's 115 degrees here and I don't cherish the idea of performing automotive repairs in this heat(this is our winter, trapped in the house). I get the feeling they have never done this on a Hybrid before and the DMCM location scares them. Maybe time to call a few other dealers.

HH-I did read that extra care needs to be taken with the wires as they get "fused" on the plugs and coils, gentle back and forth twisting or they rip apart.

 

If I were doing the plugs and wires I would upgrade to high performance sets.

 

The Stock Delco ones are 100K mile Iridium ones made by NGK, can't do much better.(NGK is an excellent manufacturer and Iridium is one of their higher lines)

Yes, I understand there is a slight life span difference between basic/standard plugs and higher quality plugs but I don't buy in to the performance claims of "fancy" plugs, that's not how ICE engines work.

My opinion is any perceived performance gains from "Fancy" plugs are most likely due to replacing completely worn out plugs that are already having issues.

Delco does sell "performance" wires(9748UU) as opposed to "Standard" wires(748UU) but I honestly think the only difference is, 1. The performance wires appear to be red(Black for standard), 2. they soak the buyer for more money, Probably same manufacturer.

Again, functioning wires are functioning wires, performance claims are snake oil, yes quality and life span are factors but performance gains are not, ICE engines don't work like that. unless you are referring to a hi-performance turbo, blown, nitrous, etc., then strong reliable spark is imperative for engine health.

Also, the wires on the Hybrid Tahoe are so short and properly shielded from the exhaust I would suspect age is the only thing they are susceptible to.

 

Lower ohm resistance wires will deliver more energy ( Joules ) in this case milli-joules to the plug. More energy in the spark is the single most and best thing where MORE is actually better.

 

Yes, this is theoretically true to a point. In non-high performance engines the benefit beyond adequate spark is miniscule.

In high performance engines, better/stronger/robust spark can be measurably beneficial.

 

Looks like I'm going to have to take this task on myself(when it get's cooler).

I called several other Local Chevy dealers and they are all extremely high priced. Judging by their reaction on the phone, I honestly believe they are afraid to work on a Hybrid. There are only a handful of Hybrid Tahoe/Yukon/Escalade's here in the Phoenix area, I drive a lot and I can literally go weeks without seeing another(and it's usually the same one-lol)

 

How about a local shop? Spark plugs are not hybrid specific. On the driver's side same as standard truck. Passenger side has lots of sharp sheet metal in the way.