How do I tell if I screwed up my oil change?

Question

I just changed my oil in my 2500 HD Silverado for the first time by myself. I've changed my oil in a 2004 Toyota Camry a handful of times, but I always had a friend supervise me. I need to know common signs that I messed up.

I took it for a drive around the block, and noticed a slight amount of smoke coming off the side of a giant pipe (I think the exhaust manifold, but I'm unsure) It's directly under my oil pan.

I did spill oil on it, but I'm worried.

The oil pressure also drift from 40 psi at idle to 60 psi with gas. I've heard that this is normal but i never noticed it before.

I checked my dip stick, but my driveway is on an incline. None of the oil looked burned, and it was a healthy brown.

I understand that I am both a total noob, and paranoid; but I would like to defer to you guys for diagnostic tips to make sure I did everything right.

Answer 1

I believe you just dripped some oil on your exhaust when drained it, don't worry, and your "paranoid" stuff is good - it means you care. Good job Snake! ;)

Answer 2

Here's a "tip to make sure I got everything right" for the future. One that I use myself, and taught my Auto Tech students as well:

The very first thing is to take off the oil cap, and place it over the latch area for the hood, such that you can't close the hood unless you move the cap.

This prevents the worst possible thing: finishing the job but forgetting to put fresh oil in. Sounds silly, but in a dynamic shop environment, the tech that starts the oil change might not be the one that finishes it.

Another thing to be careful of, is make sure the o-ring on the oil filter comes out with the oil filter. (And always lube this o-ring with engine oil before installing the new filter.) If some other tech doesn't do this, the o-ring can "weld" to the vehicle. If this isn't noticed, the double o-ring will blow out at the worst possible moment and lose all the engine oil.

And on some vehicles, Subarus especially, make sure you recognise the difference between the engine oil filter and the transmission fluid filter -- as these look identical, the same size, and are actually physically interchangable.

Just a few hints while I can remember them. The nurse has to put me to bed now...

Answer 3

I think you'll be OK. Drive it around a bit more, and that oil, which sounds like it's on the exhaust pipe, will burn off.

Your oil pressure sounds in the normal range - it's usually lower at idle (even down to 20psi is OK).

If you're really paranoid, take it to a local jiffylube or similar, and slip them $10 for them to check your work.

Answer 4

So, to answer the more general question – how to verify that everything is OK with the oil change (TL;DR - If you were reasonably careful and aren't standing in a puddle of new oil, you probably didn't, but still its nice to know how to check your work, so keep reading, its not really that long…):

1. Double check everything before you start the engine – oil reads full on the dip stick (or maybe just a hair low since it takes a bit of time to drain down), oil cap on, no leaks from the drain plug, all of your tools and other stuff out of the engine compartment. You don't want oil splashing or stuff flying around…
2. Wipe up any spills you see. If you've dripped oil onto the exhaust manifold (which is usually rusty and a bit rough) it may be hard to get it all off, as a result you may see/smell some burning oil as the engine comes up to temperature. This is to be expected if you spilled some oil in the manifold, but otherwise it is worth investigating – especially if it persists for more than a brief moment (unless you know that you spilled a lot of oil).
3. Start the engine and watch the oil pressure (some fluctuation with engine speed and a small decline as the engine heats up is probably normal) or the warning light. It should go out promptly. Get out and check for leaks, especially around the oil filter, double check the drain plug. The drain plug should be completely dry and free of oil. If there is any weeping, you might try tightening it a bit (check the torque specs, even if you don't have a torque wrench you can imagine picking up a sack of flour or something to help you estimate), but don't just tighten it more and more, you don't want to strip the threads or crack the pan. Just remember that you're loosing some oil and next time replace the gasket and/or the drain plug.
4. Shut the engine down and check the dip stick. You'll probably be down a bit since the oil filter will be full of oil now. Add enough oil to bring it right to the top (makes it easy to judge how fast you're consuming oil).
5. Verify that you've reset the service reminder if you have one.
6. Get yourself a treat.

The next time you fill up, check the oil (not a bad thing to do every time you fill up) to confirm that you're still near the top and look again for leaks. If you park in some regular places keeping an eye out for fresh drips is a good idea too.

As you start working on your car(s) you'll get more "tuned in" to them. That's a good thing, you'll start noticing things you didn't before – some will be completely normal things you've never noticed (fluctuating oil pressure) but some may be signs of developing problems (oil on the spot you know you wiped clean, the oil pressure light starting to flicker). When you spot stuff that puzzles you, ask about it – it will make the site better.

Answer 5

If you did spill oil on the engine, it can take a pretty good while before it will burn off completely. The oil pressure readings you're getting sound great. If you are getting different oil pressure readings now, it could be because you used a different viscosity oil than before, which could be helping your oil pump. The pump is basically a little propeller that's driven by the engines timing, which is why when the throttle is applied the pressure rises, much in the same way as your voltmeter, which displays the current amount of electricity being produced to run every electrical system the car has but also maintains and refills the amount of electricity in your battery, so it'll start the next time you need it to.

To find an oil leak, get under your car again, as if you're gonna change the oil, and use a rag to clean all around the drain plug, oil pan, and oil filter, especially where the filter meets the block. If it's not obvious that you just cleaned up oil from where it shouldn't have been, the next part is check those recently cleaned spots again in a day or so.

If it's still clean you can rule out the most common places oil ever leaks from. It also wouldn't hurt to get yourself a good sized cardboard box, cut it or break it down, and place it directly beneath your engine where you park. If a drop of oil drips on that cardboard you won't be able to miss it, and if it does leak, the position of the drop on the cardboard will indicate where the oil is leaking from. On your next oil change, make sure the gasket on the drain-plug isn't cracked or really dried out, and always keep an eye on your oil levels several times within the first few days of performing any oil change.

Hope this was informative enough to help.