Change Your Spark Plugs

Mar 8

Article by: RobRed

Applicable Models: 1998 – 2007 / 100 Series Land Cruiser or Lx 470

Changing you spark plugs can improve mileage and performance and make you truck feel new again. In my case the plugs went in easily and the truck runs better after 138k with originals. I just love working on the cruiser – everything is accessible and well laid out. Here’s how to do it:

For those that have not done this yet it’s very simple but you may want to have a couple of “special” tools handy.

my tool list:

1/4″ ratchet drive
1/4″ 3″ extension
1/4″ 10mm socket
1/4″ 10mm deep socket
3/8″ ratchet drive
3/8″ 16mm Spark Plug Socket
3/8″ 3″ extension
3/8″ 6″ extension
3/8″ 9″ extension
3/8″ universal extension
Shop Rag
Diet Mountain Dew

Optional Feeler Gauge to check Spark Plug Gaps (1.1mm / 0.043 in.)

Passenger side is super easy to access – tons of room. Just remove the intake resonator (black box) by unplugging 4 small hoses and removing 2 10mm bolts. Release the clamps on the engine intake and airbox output – Boom access to the first 4 cylinders. Release the coil pack electrical connections, remove the coil pack bolts and pull the packs up to reveal the spark plug. I recommend doing this one at a time to minimize mistakes. Continue this process on the other bank with notes below.

The drivers side is more challenging as there is a bracket covering half of 6,

all of 7 and half of 8. No problem, undo two 10mm bolts and the bracket is free. Plugs 5 and 6 are a breeze. Plug 7 and 8 needs a “special” tool:

Plug 7 Tool

Plug Tool 8

I was able to use a couple of differnt extension lengths with the universal and got 7 and 8 out easily. Start to finish including the air filter was 70 minutes.

I’m running the OEM Denso Iridium, 0.043″. All the plugs came gapped.