Why Aftermarket Parts Don’t Fit

Aftermarket Parts: Not Always Manufactures Fault for Poor Fitment

We’ve all experienced a brand new aftermarket part designed for our cars that just doesn’t fit. Why is that? Did the manufacture purposely design a part that wouldn’t fit? No, that’s not the case at all. There’s several reasons why an aftermarket part won’t fit, let’s go over each one step by step to get a better understanding. 

Reason One Aftermarket Parts Don't Fit: 50 Year Old Cars

The first reason is these are often 50-year-old cars built by hand on an assembly line by actual people! They were never built to the standards of today’s cars which are mostly assembled by highly precise robots. Go look at un-restored cars from the 60s, 70s, and 80s and you’ll see all sorts of ill-fitting parts and panels. That was just the norm back then. When we restore them and try to make everything perfect it can be a snowball effect where we fix one bad fitting part which then makes others fit incorrectly. Again, these cars are usually 50 years old. That’s 50 years of wear and tear, rust, repair, and whatever else. Things sag, bend, wear out, and just don’t fit. How does one reproduce a part for a 50-year-old car that was in a fender bender and has rust issues? They can only design the best they can off factory parts. 

Why Aftermarket Parts Don't Fit

Reason 2: Too Many Modifications

We are just as guilty as the rest, we modify almost everything. Not too many of us are out there creating a perfect 100% original build. We aftermarket parts such as headers which then means the original exhaust doesn’t fit anymore. We upgrade to better disc brakes so now the factory wheels don’t fit. There’s always a bit of give and take – you want better parts on the car, sometimes that comes with the cost of having to make them fit. When you add aftermarket suspension, rear end, engines and transmissions – do you really expect an aftermarket exhaust to be bolt-in around all your aftermarket parts? No. 

Reason 3: Working With What's Available

Sometimes it’s the only option. There might only be one or two companies that make a particular part and that’s all we can offer you. Other times there are several manufactures of varying quality and price points – with these, we only offer the best parts that we can. But when it’s a part that only one manufacture makes, that’s simply the best available part on the market – whether it fits perfectly or not. 

That doesn’t mean that we have to accept the parts as they are. We are constantly relaying information back to manufactures on how to improve their parts, and even going to the extent of having some of our own GM licensed products since other options were not to our standards. Mediocre fitting parts isn’t okay in our books – we want to bring you the best parts available period. We aren’t afraid to reject parts from manufactures as well if they don’t meet our standards, guaranteeing what you ordered is of the highest quality available.

By working with manufactures, we are able to help bring more and more parts to the market. We can relay to them what you are asking for and what you need for your ride. It’s another version of the squeaky wheel gets the grease – if enough people are saying hey this doesn’t fit right, or they don’t make this part, then we can go to the manufacture and ask they make it right or produce the part, again sometimes taking on the burden of tooling costs.  

Even with new cars aftermarket parts don’t always fit the best. We try our hardest to offer the biggest selection of quality parts available. Just remember that these are old cars and weren’t the best to begin with – that’s why we are all fixing them up better than new and sometimes they require a little massaging to fit perfectly. It’s not so much that aftermarket parts don’t fit, they just don’t fit to our standards today. Rest assured though we have selected the best fitting parts possible for your ride! 

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