Oil Change and Spark Plugs Question

[ttmedical]

Hey everyone, I'm about to reach 105000 miles and I figured along with an oil change I'd also replace the spark plugs. I've viewed a lot of how-to and DIY guides but have two questions.

1) Should I change the spark plugs first or do the oil change? I have an '03 so I don't think I deal with any spark plug tubes but don't know if order matters.

2) It seems that warming up the car will help make the oil less viscous and so it will flow out better but I'm not sure what temperature to get the car to before draining the vehicle. I'm honestly terrified of burning myself so I wanted to get advice on this point about safety or any good techniques.

Thanks!

[Steve Tinker]

Personally, I jack up the car (4 x jackstands) and change the oil & filter first, but it really doesn't matter.
Loosen the rear wheels before jacking up the car. You have to remove the wheels as gives you more room to remove the coil packs and plugs.

Getting the oil up to temperature is subjective, but I run the engine a idle for +/- 5 minutes before draining. If you do this before jacking up the car, it gives the exhaust (which is hot) time to cool off. Also use good quality mechanics gloves and long sleeves to protect your arms. Then you are good to go.

[cribfiller]

Definitely change oil once it has warmed up, drains better. Change the plugs cold.

[steved0x]

Yeah, the plugs will be hot as $34%&. When I do an oil change I drive around for about 10 minutes or so, giving the coolant gauge time to come up to 180 plus a few minutes.

Then I jack it up, it gives a little time for the exhaust and so on to cool down some.

If I was combining plugs with an oil change I would let the car sit for a while, a few hours, to cool down before doing the plugs.

Taking the rear wheels and the front inner fender liner will give you plenty of room to do the plugs.

Alternately, if you didn't want to wait that long you could jack the car cold, do plugs first, then run it for 10-15 minutes to warm the oil, then drain and do oil change.

I prefer method 1 and hotter oil, I always let it drain a long time. It keeps coming out, it will surprise you.

[mikesz]

Just be ready when the oil starts pouring out. It comes out FAST and if you are not careful you will be swimming in it.

[CoBeerToad]

Originally Posted by mikesz

Just be ready when the oil starts pouring out. It comes out FAST and if you are not careful you will be swimming in it.

Had some fun the last oil change I did. I used one of those drain pans that have a hole in the top and it plugged up on me after about a quart drained. Naturally, this time, I didn't pay attention and went in the house to let the oil drain. Came back out to about 8 quarts of oil on the ground.

I was also planning on changing the center mount and draining the coolant. Got to lay in moist kitty litter for all that fun. A mistake I will not be making again.

[dghii]

Change oil hot! Get some disposable gloves and you won't feel a thing!

[911monty]

I would suggest doing these as 2 separate jobs. Reason being you want the oil hot to change, BUT you want that engine STONE COLD to change the plugs. The aluminum cylinder threads strip/gall very easily. Also, break the plugs loose, then try to remove by hand. If the plug gets tight then reverse and screw in and work back and forth. Carbon on the plug end can also damage the threads. When installing be sure to use a good type anti seize (copper) on plug threads, and torque carefully. Take your time, do not rush this job. Good Luck

edit: just saw the question on safety. The oil is Hot, but is not going to scar immediately. Just have a rag to wipe off. To keep from burning fingers on the hot drain plug I recommend using the allen wrench to unscrew the plug. This way you keep upward pressure up against the case and when you feel the threads jump as it is completely loose just tilt and pull the wrench toward you. You control the drain and don't lose the plug in the drain pan, that can plug the drain holes. Thanks CoBeertoad.

[particlewave]

There is absolutely no reason to warm the car up before changing the oil. If you recall, the last time that you shut the car off it was warmed up, so all the oil already drained down into the sump.

By warming the car up your circulating oil through the engine. When you go to drain it, though it may run more freely, it has to drain out of the entire engine again. Warming the car up is completely unnecessary.
I don't see any benefits.

[911monty]

While the maximum oil is in the sump when it has been sitting cold, I believe the intent of hot oil is to circulate any heavier debris/contaminants back into the oil that have separated and settled into the bottom of the sump where they can then be removed when the oil is drained. Since the heavy materials are on the bottom they tend to resist flow and remain in the sump.

[Gilles]

Originally Posted by 911monty

While the maximum oil is in the sump when it has been sitting cold, I believe the intent of hot oil is to circulate any heavier debris/contaminants back into the oil that have separated and settled into the bottom of the sump where they can then be removed when the oil is drained. Since the heavy materials are on the bottom they tend to resist flow and remain in the sump.

+ 1

I also believe that this was the main reason for changing the oil hot..
folk lore..?

[particlewave]

Sounds like a bunch of Internet-based hogwash to me.

Never heard of such a thing in my years as a mechanic when I was younger. Never heard of such a thing from my father or grandfather who have a combined 70+ years of experience as mechanics between them.
I guess it can't hurt anything, but I'll stick with cold oil changes. Whatever floats your boat!

[cas951]

my preference is to warm up (Not Hot) the car to circulate the oil in the system and let it cool a little before draining the oil. The reason for this is you want some oil in the journals before starting the engine after the oil change. Keep in mind the oil filter housing is empty when you change the oil and new oil will take a little time to reach the journals. This is a safety precaution. I normally allow the oil to drain about an hour to try to drain as much as possible.

The engine should be cool when changing the plugs. This is for your own safety as well as the engine when removing hot components.

[jdraupp]

Originally Posted by Gilles

+ 1

I also believe that this was the main reason for changing the oil hot..
folk lore..?

I thought it made the oil drain faster?

[dghii]

If changing the oil cold, what kind of oil should the OP use?

just kidding...

Our forum could turn a discussion about air pressure into an oil thread without even blinking!

[stelan]

Originally Posted by dghii

If changing the oil cold, what kind of oil should the OP use?

just kidding...

Our forum could turn a discussion about air pressure into an oil thread without even blinking!

No kidding!
I change the oil cold but I let it drain overnight

[Dlirium]

Originally Posted by mikesz

Just be ready when the oil starts pouring out. It comes out FAST and if you are not careful you will be swimming in it.

boy did I find that out the hard way :-(