In my repair shop, I see some really dumb mistakes that, well, they’re pretty common. First, we have cartridge type oil filters these days, and on most cars that use them, they have a plastic housing that screws into the engine. Well there’s a special tool that has to grab these fingers on the outside. You try to do it any other way, like this guy did with a great big pair of channel lock pliers, you break the plastic and you have to buy a new one. This leaked when the engine got hot. Sixty five dollars down the drain.

Alright. Regular drain plugs: if tight is good, then a whole lot tight is better. Wrong. It is not. First, you may strip the threads in the oil pan; very common. Or you may strip the threads off of the plug itself; also very common. And almost always you’ll destroy the seal that is part of many of these modern drain plugs. Don’t tighten it too tight. It has to be the proper amount of tight.

Lug nuts. What could there possibly be with lug nuts? Well here we have a two piece lug nut that has this chrome plated cover on it to make it look good. But what that does in certain parts of the country…what’ll happen is that moisture will get up inside it, and it will freeze. And when it does, it causes that cap to expand. But, in every part of the country you’re going to find a technician that’s going to use one of these miserable air impact guns on them, and that distorts them.  So what do you wind up with? You wind up with a lug nut that has expanded to the point where you cannot get any wrench over the nut. So you’re out beside the road; your lug wrench in the car won’t fit. You have to be towed; you have to have the lug nuts chiseled off. Hundreds of dollars in many cases. How do you prevent it? Well, one way is to replace the lug nuts before they swell up like that with one piece nuts. Sounds extreme. But it’s a lot cheaper than towing and chiseling and things like that.

Alright here we have something that is often overlooked or cheated on. This is a seatbelt pre-tensioner. The airbags deploy, this thing has a charge in it that expands, and it pulls this cable tight. That cable then pulls down on the seatbelt buckle, the seatbelt holds you in the proper position so that the airbag protects you instead of hurting you. So these have to be replaced every time the airbag has been deployed. Make sure that it happens. Make sure that you get the old one in return. Believe me, there are some people out there, they’re dishonest and they know how to make this appear to have been replaced. And if you have a question or a comment, drop me a line, right here, at MotorWeek.