Jarm, I changed the plugs in my '08 LS 460 at about 65K (about 35K ago). The job was fairly straightforward using normal tools, but with a couple of minor exceptions. First, I had to (very gently) lever the valve head covers away (just a fraction of an inch to rock the engine on it's rubber mounts) from the inner fenders with a 2x4 to get enough clearance to get a socket extension bar into position to loosen and tighten the middle plugs. Second I had to dismount and disconnect a crowded electrical bracket in front of the master cylinder to make enough space to turn my socket wrench arm on the left rear cylinder. Other than that it's just a sequential process of unbolting each of the cylinder coils, pulling the coils off the top of the plug and removing the plug - then everything in reverse. (I usually ensure correct plug threading by first slowly turning the plug counterclockwise a turn or so until I feel the threads seat and then retightening it in by hand until it bottoms out. It should turn easily until tight - if it stops or binds from the start, it's probably cross-threaded and you should back it out and start over to prevent damaging the threads.) Once hand tight, torque the plugs to spec with a torque wrench to make sure you don't strip the threads. (Oh, and one other tip - make sure your spark plug socket mounts snugly on the extension bar. Or else the rubber "grabber" - not sure if that's the technical term - that's inside the socket to hold the plug in place for removal and insertion into those deep plug wells, might cause the extension bar to disconnect before releasing the plug when you try to extract the socket after installing the plug. If that happens you can try reinserting the extension bar and wiggling the socket around to get the rubber to release before the extension bar disconnects from the socket.) Hope this helps.

 

I just had mine changed at the dealer it was 416 for just the spark plug change.

 

If you have changed your spark plugs, did you experience smoother idle/quieter engine?

I have 2008 LWB with 48K miles and hoping that changing spark plug will help improve idle and engine noise, specially at cold startup.

Thanks in advance for any help!

 

I just changed plugs yesterday at 60k (07ls460) and no difference in idle or noise. Sorry,

 

+1, I had same experience changing out at 73K mi (08 ls460). If anything seemed slightly smoother when accelerating

 

I just got four quotes to change the spark plugs in my 08 LS600hL and the cost ranged from $499 to $730. All were dealers relatively close by, no idea why the range is so high.

 

Tony. good post. What if we just wait for 100k miles on my 2008 ls 600hl? Your opinion? Is it the same engine as the 2007 ls 460 on the 2008 ls 600 also?

 

I planned on not to replaced until it hit 100K miles, since most owners didn't feel a different.

 

A big shout out and thank you to Tony P!!!

 

On my old 460 I changed them out at 115K, it was no difference and my tech said the old plugs looked used but fine. I'm 62K now and thought about changing them but I might just hold off based on my passed experience.

 

If anything, order the plugs yourself and pay for labor only. Lexus of South Atlanta or Sewell have good pricing.

 

So I changed my plugs OEM $80 bucks off of ebay, it wasfairly cut an dry although I was nervous of the amount of force I had to applyespecially to the driver’s side coils in order to get them out. The batterytray bolts were very rusty and what I thought was a nut that would not turnended out being a different size, upon further investigation below the tray I discovereda clean new shiny 10 mm bolt directly below and lodged apparently since lastplug change. All plugs were correctly gapped and seemed to be in fair shape I wasn’texperiencing any hesitation or drivability issues actually I think my MPG isabout average from what I read here, I changed them because I was at 120,000 myconcern is two plugs on the driver’s side and passenger had small amounts ofoil residue on them. The car has sat all weekend after driving for 154 milesfrom Ft. Campbell KY to Elizabethtown KY, and the plug directly beneath thebattery tray was the worse with oil that would not drip but was very close tothat effect. Can someone help me with how to add pictures and I will post theones I took.

 

If you click on the yellow square, which is 5th from the left while I am typing this reply, it will open a new window.. Click on the browse button and go through the upload process.
If you are taking pictures with your phone, use an app like image reducer which will reduce the file size.. this is not necessary but I don't know if there are any file size limitations.

Is the oil coming from inside the cylinder chamber or a drip from the outside of the engine?

Absolutely I am no mechanic.. Hopefully, a lexus tech will answer.. but just an observation/question:
If the oil is on the outside of the engine and dripping on the plug, You might want to inspect the gaskets.. I hope it is not cylinder head gasket.

 

I just changed mine recently with OEM Denso Plugs purchased off eBay (roughly $90) using Roadfrog's DIY found on this forum. Install is very easy and can be done in less than 2 hours. I was shocked that after 130k miles, the plug chambers were as clean as they were.

 

Below battery tray I am not sure what the black item on the round piece is but i notice now there is resodue there also.











This is the worse one its below the battery tray.