When do I need a tune up? 130K miles

Jworks · May 29, 2021

I have 2011 Sierra, 5.3. Runs good; no issues. As far as I know plug wires and plugs have never been changed. Dealer says $500-600 for a tuneup. Local garage I trust says $200-300 and said somewhere around 100k miles is generally time to tune-up. One of the two (can't remember which one) said its expensive because each wire had its own coil. Wow, didn't know that !

It "seems" the truck may not be getting quite the mileage it use to get. But, there is no flat ground here in north Alabama to give it a good test. On a 400 mile trip last summer (mostly level ground) the computer said it got 21 mpg. What little flat area I can find locally is limited and the computer shows the engine running at around 19-21 mpg..... at that point in time. I don't know if thats reliable or not. With 130k miles should I pay the price and do the "tune-up" or just leave it alone? Should wires and coils be changed?

Edited May 29, 2021 by Jworks
shortened wording

Grumpy Bear · May 30, 2021

Buy plugs and wires and change them yourself. Coils don't need changing "just because".

CamGTP · May 30, 2021

GM says the plugs should be done around 100,000 miles.

New OEM plugs are like $8-9 each and a new set of wires is $50ish. Obviously shops will upcharge on parts, then it's just the labor to install. That's basically it for a tune up, not much else you can do. Personally I'd spray down the throttle body and clean the MAF sensor with MAF cleaner and that's about it.

diyer2 · May 30, 2021

Ever heard of an owners manual?

Change the plugs.

KARNUT · May 30, 2021

Many years ago when I hit 100K miles I asked my shop owning friend that question. He knew I usually trade in before 130K. He said when the light comes on. I bought a set threw them in my tool box. I kept that one until 180K, no plugs. That was an 04 Z71. My wife’s car has 110K on it. It’s stays in town. I’m going to wait it out. It’s been so long I can’t remember the last ( tune up). I looked at it this way. Do we change water pumps, alternator, power steering because they may go out? How about batteries, lights, radio? They use to end most maintenance logs in the owners manual at 100K. That gives an idea of the life expectancy of a vehicle. In reality it should be around 200K average. The stuff I mentioned is a pain to change in comparison. There’s no schedule on those. A water pump or alternator will shut you down. A little miss fire will not.

Jworks · May 30, 2021

Grumpy Bear, I guess I was wrong; I was thinking the coil already came built on to the wires. I use to change my own plugs and wires, but that was many years ago....at least 20 years ago. Its all different now I suppose. When they told me each plug had its own coil I just assumed (apparently wrongly so) that it all came built together -- wire and coil as one unit.

Grumpy Bear · May 30, 2021

39 minutes ago, Jworks said:

Grumpy Bear, I guess I was wrong; I was thinking the coil already came built on to the wires. I use to change my own plugs and wires, but that was many years ago....at least 20 years ago. Its all different now I suppose. When they told me each plug had its own coil I just assumed (apparently wrongly so) that it all came built together -- wire and coil as one unit.

They keep it intentionally confusing sir. Watch a Youtube on plug changes to these critters. Save yourself a few hundred or find a more honest shop. Hint, dealer ain't it.

Ruger · June 2, 2021

Your 5.3 getting 19 to 21 mpg? Wow. My 2013 Z71 getting 13 mpg

Jworks · September 10, 2021

Ruger, yes that is correct. Mine is a z71 4x4. I just have regular tires on it....nothing big or overdone. Where I live its not level ground. I get about 17 around locally. But flat out its 19 min. up to 21. I made a trip from Birmingham down to the gulf coast once and back...a trip of about 600 miles. Below Birmingham it starts flattening out. Just before I got home the computer hit an overall avg of 22. On average though its 19-21. I have a 6 speed trans, 3.08 differential.

Edited September 10, 2021 by Jworks

swathdiver · September 12, 2021

On 9/10/2021 at 10:12 AM, Jworks said:

Ruger, yes that is correct. Mine is a z71 4x4. I just have regular tires on it....nothing big or overdone. Where I live its not level ground. I get about 17 around locally. But flat out its 19 min. up to 21. I made a trip from Birmingham down to the gulf coast once and back...a trip of about 600 miles. Below Birmingham it starts flattening out. Just before I got home the computer hit an overall avg of 22. On average though its 19-21. I have a 6 speed trans, 3.08 differential.

Mileage is spot on, did you change the plugs and wires? How about all the fluids?