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Check the back page of your manual for the correct amount of oil. The AWD version needs 6.8 quarts.
Things you'll need, include:
7 quarts of 5W30 oil. - around 35 bucks(walmart); I used synthetic, it's cheaper if you use conventional oil.
Oil filter. - $6.55+tax(lexus dealer) Lexus Part #:04152-YZZA5; Wix Filter: 57173
Drain plug gasket. - got it for free, a pack of 3 similar ones was $2.33(local auto parts store)
Paper towels. - It gets messy no matter how hard you try
One time buy
Oil Filter Wrench - $3.26(walmart) Made by Imperial(65/67mm - 14 Flutes)
Latex gloves - Keep your hands clean, not required.
Eye protection. - Highly recommend this. Dirt and Oil can get in your eyes.
A pair of jack stands. - ~$20 for a pair(walmart).
Instead of jack stands you can buy a pair of ramps.
Oil pan(something to collect the old oil). - ~$10(walmart)
And a funnel. ~$1
Things most people have
Size 14 wrench - Lexus roadside kit
Scissor jack - in the trunk
3/4-inch socket wrench - you should have this
Screw drivers, flat head and phillips - phillips is in the Lexus kit
Old cardboard box split in half to lay down on.
You'll need the phillips screw driver for the one screw on the plastic underbody filter cover. And a flat head one for many uses.
This is the official Lexus gasket that I was provided with
You'll need this cup thing(filter wrench) with the help of a socket wrench for the removal of the oil filter casing(metal). A 6" extension for the socket wrench helps a lot.
The filter on the left is the one you'll need. The one on the right is the wrong size and it only works for the RX350. If you do decide to go with WIX, the part number is 57173 - but keep in mind that at my local auto-parts store it came out to be more expensive - ~$9.
I chose to use the 5W30 Synthetic from Castrol. You can choose any other oil as long as it's 5W30.
If you want, you can check your oil level before starting, here's how to do it. Pull out the dip stick(on the right side of the car), wipe it dry and reinsert, then pull it out and look. It seems like the Lexus guys over filled my car. Your oil level should not be higher than the top mark. The distance from the top to the bottom mark indicates about 1 quart. So if your level is at the bottom, add one quart of the same oil from the same company.
Put the Parking(Emergency) Brake on before lifting the car up. Also do not sit in the car and try not to move it around while it's up on jacks stands(common sense).
Using the scissor jack, raise the car as high as possible and then set it up on jack stands(do this on both sides). Make sure you're parked on a flat ground and don't ever go under a car that's only supported by a jack. Always use jack stands(in this case)
This is the oil pan. There is a similar pan more to the back of the car - make sure you don't go to it. Since I almost did. The other one is for your transmission. Place your container for catching the oil underneath.
Untighten the drain plug with the size 14 wrench until it gets loose and then finish by hand. Get ready for the oil to come out and let it drain. The old gasket was stuck to the oil pan so I used a flat head screw driver and pulled it off from the inside of the ring.
The filter cover is labeled "IS 4 WD". You will need to remove the one screw at the top and once you'll try to pull it, there is gonna be a clip holding it down. Remove that too by pulling the inside part out with a flathead screw driver.
The clip and the screw that you need to remove from the cover.
You'll realize that the plastic filter cover is actually attached to the whole underbody so you'll just need to open it like a door. Behind it is the oil filtercasing(metal). Place the oil pan underneath since it's gonna leak. Using the cup-like filter wrench and a socket wrench(an extension of about 4" helps), untighten the casing and then finish opening it by hand. The manual suggests to open up the little cover and drain the remaining oil before removing the casing(which I forgot about). So it got a bit messy and oil came out of the sides.
After removing the filter casing, wipe off the mess. If there is any...
Remove the old filter from the casing along with all the old rubber seals. My filter wrench got stuck to the casing so I had to use a hammer to get it off.
There is a small cover on the actual casing which you can use to drain the remaining oil, before removing the whole casing. But if you didn't do that and just removed the whole thing, open it up now and remove the small rubber seal and replace it with a new one. It's easier to pick it up with a flat head screw driver. Before !Removed! the cover back on, apply some fresh oil onto the rubber seal for easier removal in the future.
Insert your new filter into the casing and change the rubber seals with the ones you're provided.
Put everything back together (new oil filter, and two new rubber seals). Don't forget to coat the o-rings with some new oil. Clean up any oil that's on the car with paper towels. You should also wipe the casing so that you could tell if there are any leaks later on.
After you put everything back together start to pour the new oil in.
You should end up with this much oil(.2 of a quart) in the last 1-quart container.
Start the engine and let it run for no less than 3 minutes. At this time you can start cleaning up your tools. While the engine is running, check for any leaks on the filter casing.
And around the drain plug.
If everything is okay, turn the engine off and check the oil level with the dip stick(just like in the beginning, it should be at the right level). Close the filter cover and put the screw and the clip back on. Now you're done, just lower your car by raising it up with the scissor jack and removing the jack stands one at a time. Close the hood and finish cleaning up. You can drain your used oil and get rid of the used filter at a local gas station(that has a service building).
Congratulations, you've just completed your own oil change!