Well, tell that to a friend of mine who does their own oil changes. They installed the steel plug into the aluminum pan and torqued it to spec. Three hundred miles later the plug fell out. When they installed a new plug, there was nothing wrong with the threads in the pan.
Needless to say, they now tighten the plug a little over spec.
Tester
Sorry, but I stand by my post. A properly torqued plug in an undamaged drain hole will not fall out. Assuming, that is, that the plug itself hasn’t been changed to a shorter plug somewhere along the line.
Well I do it my way because it takes a while for the oil to drain and instead of having a smoke, I work on the filter. By the time I’m done with the filter, the oil is drained. Its smoother that way and no oil dripping on my arm. I just have to make sure I tighten the plug afterward. Minimizes the times I have to get down on the ground and crawl under the car again too. On rare occassions of memory loss where I can’t specifically recall tightening the plug, I just have to crawl under again and check it. I spose I could use two ratchets, but this has worked for me for 50 years and never had one fall out.
I use a new washer on the Acura every time because the book calls for it and it has a cast aluminum pan. On the others that have a stamped steel pan, I re-use the washers unless they look worn or there is leakage.
Nylon drain plug washers are so deformed after using them, you’d really not want to reuse them
I don’t trust nylon washers. When I said I reused washers sometimes I meant metal ones.
@mustangman, sorry, I hit your disagree by mistake while trying to hit agree with Bing.
Danged little buggers are so easy to touch by mistake on iPad.
I always use the same type of washer that the factory put on
If it originally came with nylon, that’s what I’m using
My old Toyota pickup had a nylon washer. I too always use whatever the vehicle came with. and I agree with your earlier post that nylon washers deform and should not be reused. But I’d be lying if I said I never reused one… I’ve run out on occasion.
I agree with @Whitey. There are many who wouldn’t think twice about using a lock washer of locking nut or a castle nut with a cotter pin for critical holding power but somehow think that reusing the same oli pan washer which essentially becomes just a flat washer after being used, is OK. The entire motor depends upon that one washer and we still reuse the same one.
I recently had my transmission fluid changed at a DEALERSHIP and left the car with a friend while we went on vacation. We asked him to use it as much as he wanted as they were due for snow and the car was Awd with snow tires, neither of which he has.
When we returned, he said the car was leaking pink fluid on the snow under the car on his drive. I quickly checked the plug when we returned, snugged it down and still saw leaking around it. Because It still had sufficient fluid in it, I took it back to the dealership. It seems they had reused the same washer ! WTH ! I asked them to drain the fluid out again, add a new washer, then refill with fresh fluid at their expense. They did, sheepishly. No one it seems thinks it’s important to put on a new washer…even those who should, till it’s too late.
Aaaarrrrrrrrgggggggggggggg!!!
Those choices make me shudder!!
OK…I’m not saying that replacing the washer or torqueing the drain plug is not a good idea but… I never replace the washer unless it’s damaged and I never torque the drain plug on my own vehicles. I’ve never had a drain plug fall out and I’ve never even had one come loose. I do, however, always remember to make sure the plug is tight and that it doesn’t leak when the oil is added to the pan. I must also confess that I never just hand tighten the oil filter…I snug it up with the oil wrench. If I remember anything else I do against the book…I’ll let you know later.
I agree that reusing the crushable washer does not gurantee failure. All that I would like to reinforce is that adequate and correct torquing IMO, is best done with a new crushable washer. Can you crank it down enought to “never” have a problem ? Of course, the same in just about any nut/bolt application. But, appropriate procedures minimize the chances of leakage while still not stressing the threads by just cranking it down over time which results in that type of failure.
Just using a washer of a softer metal helps retain some holding power which is what my tractor oil pan bolt uses and it never requires replacement. But, i bet the threads are much, much deeper and the pan is much heavier with much more holding power and resistance to thread damage; know that for a fact ! I never have a problem with leakage. But, a tractor, a lawn mower and a car all have different requirements and I would guess for different reasons. Cars are getting lighter and lighter and thread depth may be less then other equipment.
Again, it’s amazing how we expect the drain plug which is some times bathed in a lubricant to hold as well as nuts and bolts in other places we would not think of using without the aid of a locking nut, or locking washer or cotter pin. Washers have several applications and one is for holding power as well as leakage. Lock washers have little leakage control but crushable ones have both functions. Personally, when not installed as directed, I’m surprised there aren’t more problems. That’s probably because many change their oil sooner then they have to…
Double checking is ALWAYS prudent!
I tighten the filter wrist tight only, but I wipe it down and use latex gloves, so I’m able to apply decent torque to it. The latex gloves act like the rubber jar openers… the less energy expended getting traction on the filter (or jar lid) is the more that can be applied to torqueing the filter (or jar lid).
@sameMountainbike
I respectfully disagree about a properly torque bolt in undamaged threads or drain hole will not fall out. It may not fall out in the time between your oil changes but with out the aid of a properly installed washer, it will fall out sooner and or be prone to leakage sooner. There are bolts on the chassis that regularly need retorquing over time and are installed in undamaged areas. But, because of their potential failure being a consideration, they need retorquing . These bolts are not protected by cotter pins and castle nuts and can’t be because of their use. It is assumed that drain bolts are “protected” buy proper installation, including washer replacement and should not fail between oil changes. The longer the oil change interval, the greater the need to follow directions. Retigtening an oil pan bolt or having to defeats the purpose of using a crushable washer. But, like I have said, if you change your oil sooner then the recomended interval, you will probably never experience any failure by not following directions. But, if your recomended oil change interval is 10k miles, doing it right becomes much more important. It is in many applications including municiple vehicals that use synthetic oils with much longer oil change intervals.
If some of you don’t want to bother with a fresh crush washer on your personal vehicles, I’m okay with that. You’ve weighed the risks, and if there are consequences, you’ll be the ones dealing with them. However, anyone who doesn’t use a fresh crush washer in a professional setting is a hack.
There. I said it.
Ehh, the discussion about why drain plugs fall out has left out about (my guess) 50% of the cars out there now. They use neither a crush washer or a nylon/fiber gasket. What about the o-ring that is an integral part of the drain plug? Surely we aren’t supposed to replace the actual drain plug at every service.
Dag, I absolutely agree that it has to have a proper washer. It was not my intent to omit that, I was just focusing on the thermal expansion coefficient question.
ASE, O rings perhaps don’t need to be replaced at every change, but if mine had one I probably would get in the habit of doing so, just so I don’t forget and neglect it when the elastomer gets old. Besides, elastomers “cold flow” too.
Some people never expierience certain things in life, and therefore, never think it can occur.
Tester
Curtain things? Or certain things?
Sorry, I couldn’t resist. 
All of the talk about the difference in thermal coefficient of expansion of steel vs aluminum could make one worry about steel spark plugs in aluminum heads. That said, I have never lost an oil pan bolt nor a spark plug from many bikes, all with aluminum crankcases and heads as well as many cars with aluminum oil pans and heads. The difference in heat expansion of the two materials is compensated by elasticity if the tightening torque is sufficient.
Without using a torque wrench, “tight” can result a large difference in torque from different people.