When replacing automotive fasteners on your truck, car, SUV, or motorcycle, you should consider a few things before you start. They may be small, but these fasteners are vital to the functionality and safety of your vehicle.

Replacing automotive fasteners improperly can cause more harm than good, damage your vehicle, and cost you more money in the end. Whether you’re replacing fasteners in the spark plug ports, oil drain plugs, transmission, carburetor, exhaust and intake manifolds, engine block, brakes, or anywhere else, consider these five things before you start.

1. Do the Automotive Fasteners Need to be Replaced?

Firstly, consider if you need to replace your fasteners at all. You may think that they need to be replaced after a certain time, but a quality automotive manufacturer will invest in state-of-the-art nuts and bolts for its vehicles—these fasteners are strong and coated to protect them from the elements. Before you invest your time and money in replacing your automotive fasteners, check out how they’re holding up first.

2. Removing the Fasteners Safely

Having the right tools is the first step to removing your old, broken, or worn out fasteners safely, but it still takes skill and knowledge to ensure you’re not stripping out threads entirely or breaking or rounding off screws—which is just going to make your project more difficult and frustrating. There are some tricks to removing your broken fasteners—use penetrating fluids, apply heat to immovable fasteners to cause expansion, or use friction enhancers to fill in the damaged areas first.

3. Don’t Buy Cheap Parts

You shouldn’t be replacing the original fasteners with cheap new ones. If you’re going to replace them, make sure your new bolts, nuts, or screws are high quality and right for your automotive application—from their size and material to the coating used to protect them. If you cheap out on these new parts, you’re going to quickly realize your mistake when they break on you.

4. If in Doubt, Go to a Professional

Removing and replacing automotive fasteners isn’t an easy job. A lot can go wrong fast and you could be causing more harm than good. If you’re not sure you have the skills or experience to do it correctly, go to a professional who can do the job safely and effectively.