Romanova

Today I changed out the plugs on my '12 with 107k on it. This isn't a step by step how to, but some general observations and tips for the next person. Let me say that this was a challenging job... almost everything is in the way. I thought plugs were hard on my old V10 Excursion... no, I would say that the GX was harder. If you have the right tools and some patience, you can knock it out though. Total time was probably about 90 minutes or so.

I started with the driver's side first and went one at a time. The plugs for the COPs were all pretty difficult to remove, especially when you get towards the firewall and things are in your way. Some required using long needle nose pliers to squeeze the clip and then they would pop out. There is one bolt for the fat wire harness that runs down the valve cover, make sure you take that off to have some room as well as the plastic cover by the master cylinder. The COPs came out easy, no problems. The plugs came out easy too with enough extensions. The ones at the back required some creative work getting the socket on the plug, but was then easy after that. I torqued the plugs to 15ft pounds per the manual and just snugged up the bolts on the COP.



Had to pop this plastic piece off the fuel line...

Last one on the driver's side was a challenge... just have patience and it will come out.

Prepare to curse accordingly...


Passenger side was just as challenging. Take off the plastic cover by the firewall, as well as the airbox (top and bottom). The bottom part of the airbox has 2 12mm bolts inside and one on the outside in the back. Mine was full of deer corn from where the previous owner had it out in the country. No signs of mouse turds or anything like that, thankfully.

The passenger side has a similar wire harness except it has two bolts to remove. Keep a magnet handy for the second one as it is easy to lose when it comes off. I lost mine. The plug for the MAF is on a plastic retention piece, pop it off and move it out of the way.

From the front, the 3rd one back on the passenger side was the hardest out of all of them. Everything is in the way. If you do that one first, the rest will seem so much easier!

Tools used. Several 3/8th ratchets, one 1/4 inch ratchet with several extensions and a universal joint. The spark plug socket is a flex unit from Gear Wrench. Did NOT need a 3/8th universal joint, though it might have made the job only slightly easier. You can also see the needle nose pliers for some of the COP plugs, as well as the telescoping magnet and torque wrench. Had everything on hand.


I used new OEM plugs that matched the ones that came out. I think they are the same for 2010-2013, but 2014+ might use a different plug.
Again, a do-able job for most people. I really wouldn't want to do this again, but it would be much easier the second time around.
Good luck!

Acrad

Thanks!! Really good info.

Looks like everything was dry in there and no oil. I'm not gonna change the plugs for quite a number of years since I am only at 43K but will be pulling the coil packs before next May to confirm mine are dry too.

Romanova

Should add that I didn't use antiseize... didn't feel the need to. Also, I could have put a dab of dielectric grease on the COP tips, but with the upper gasket on them, it seemed to keep the tubes free from dirt intrusion. I did remove the upper gaskets to clean and condition them.

tecman

Thanks for this info. I changed the plugs on my last 3 Acura’s and other cars. I looked at the GX layout awhile back and decided I didn’t want to deal with the frustration. This confirms that I will pay the price for a reputable mechanic to do this.

Rufio

I’m with you. I might bite the bullet in the next year and drop OEM plugs at the dealer and save myself the headache. I wonder how much the dealer charges for labor only.

mceagle555

Figured I would add a bit of info to the DIY Spark Plug page. I just changed mine out today after purchasing my 2010 GX460 Premium this weekend. Below are high res pics if you want an idea of of what 10-year old, 106k mile spark plugs look like.
.

• 2010 GX460 Premium
• 02/2010 Build Date (10 years 2 months on plugs)
• 106,000 Miles
• Plugs are in order as they would appear in the engine

LexusGXFan

Sounds like another project to do yourself to make sure it's done CORRECTLY !!!

Thank you for posting

ObsidianBl

Can someone help interpret @mceagle555 pictures? Do they look okay for the time and mileage? I’m trying to learn by looking at pics online, but i figure asking will be the best way.

bbqsoup

I'd say they look pretty good at 106k. There was no visible oil and no burn. The tips are still in good shape with no rounding or became flat, which could be a sign of running too hot. They don't look wet either so that's a good sign of not running too rich.

nuclearn8

Agreed. Plugs look to indicate nothing abnormal and a best case scenario for 106k miles.

mceagle555

Agreed! While they look quite dirty, they are 10 year old plugs. I checked the gaps and ironically they were still gapped to spec. (Amazing)

I will say that they definitely felt "gummy" pulling them out for the first 2-3 turns of the wrench. I put a small bit of permatex anti-seize on the replacements and they went in smooth as silk.

Truck started up just fine, though I find the GX460 to really "roar" up to 1,500-1,600 RPM on first start, then settlle down to idle around 1,100-1,200 RPM when in park. (Can others compare?)

bbqsoup

Mine is pretty loud at first start too. I think the air pump kicks in when cold.

nuclearn8

standard for any fuel injected car... the idle revs come down as the engine warms up. it's just more noticeable than on the smaller NA 4bangers

Romanova

Compare them to mine which had about the same mileage. They look fine to me.

WRD4chano

probably too soon to take notice but, have you notice any increase in mpg?