More new bolt pattern/offset combinations have emerged in the last few years than in the last 20 years combined. Remember when there were only a dozen common bolt patterns, and almost everything had a standard offset? Oh, how I long for those days.
Today, though, we have double that number, and it seems we are bombarded with another oddity every year. If we don’t keep our training current and apply the principles we’ve tackled over the years in this column, there will be a lot of room for error.
First, we’re going to take a look at one of the most common and heavily accessorized platforms in the industry the new Ford F-150 and Expedition/Navigator. Ever since Ford came out with the 5-35-mm bolt pattern with medium offset, the wheel industry has had to produce another series of SKUs to fit these vehicles.
Then, just when the wheel makers were hitting a good stride, along comes the 6-35-mm bolt pattern with a high positive offset. You might remember that, in the last few Wheel Turnings articles, we looked at how much it costs to build a wheel mold. With that in mind, it’s no wonder the wheel manufacturers are drilling this new bolt pattern into existing wheel styles.
But here’s the dilemma. The OE wheel for these trucks is 17×7.5 with a +30-mm offset. That is as high as most front-wheel-drive vehicles. Now, look at where the tire sits in relation to the fender (Photo A).
Notice that the OE tire is flush with the top of the fender. If you sell a wheel to a customer with no regard to width or offset, this is what can happen. In Photo B below, you can see how we have simulated where various wheels would sit in relation to the fender.
All of the width and offset combinations simulated here use wheel dimensions currently in production at several well-known wheel manufacturer plants.
The first panel shows the tool simulating a 20×8.5 with a +35-mm offset. You can see that it is at near-stock offset. This provides a nice plus-size application. The second panel shows where a 24×10 with a +35-mm offset would sit. Notice that we have split the extra 1.5-inch addition from 8.5 inches and only one inch sticks out farther than stock. This isn’t too far, but considering that an Expedition/Navigator is a luxury vehicle, your customer may not appreciate the side of his or her new SUV being pelted with mud and rocks. Use this opportunity to sell fender flares to provide a smooth look and protect the paint.
The third panel shows where a 17×9 with a 0 offset will sit. Notice that the width is narrower than Panel 2, but the offset pushes nearly 1.5 inches farther out than stock.
The fourth panel shows a 18×9.5 with a -19-mm offset. This is for a lifted suspension application. An important point to note: Don’t assume that a wheel with a 6-135-mm bolt pattern will fit a customer’s vehicle the way that he or she expects.
Notice the offset before you order your wheel, and educate your customers. I promise they will appreciate the effort. By the way, Ford replaced the two-piece mag/washer lugs with solid conical seat lugs on these trucks (Photo C).
It only took five years and two recalls, but I’m glad they came to their senses. Also, be sure to check torque charts. On some trucks, these 14-mm x 2.0 lugs require 150 ft-lbs. of torque.
Another vehicle that can potentially cause a problem is the new Chevy Colorado/GMC Canyon. The issue with this truck isn’t so much the bolt pattern and offset as it is the hub diameter. The truck uses a standard 6-5.5 bolt pattern and medium offset like the full-size GM trucks, but it has a large hub (Photo D). For several years, the aftermarket has been building hub-centric wheels for GM trucks. When the 1999 trucks and 2000 SUVs arrived, there were several vibration issues you couldn’t avoid unless you used a hub-centric wheel.
The wording in the box indicates 100 mm (compared to 78 mm for full-size trucks). As you can see, the hub is more than 20 mm larger. That means if you try to install a wheel that is labeled “6-5.5 GM hub-centric” on these new mid-sized trucks, the wheel will not fit over the hub but, instead, rest on the outside edge. You’ll need a large-bore wheel, usually 4.25, that would normally fit Nissan and Toyota.
Two other vehicles to watch for are the new Dodge Magnum and Chrysler 300C. These cars are often candidates for restyling, and wheels are the first things customers want. But the biggest issue is the bolt pattern.
For as long as it has been in the car making business, Chrysler/Dodge/Plymouth has been using 5-4.5 bolt circle applications. Well, guess what? The two new bad boys from Detroit are using a 5-115-mm bolt pattern, like the one GM has been using since 1988.
The Magnum/300C also uses a medium offset. You may be asked to put on a 5-4.5 bolt pattern with a medium offset wheel that will fit an older Explorer/Mustang. Apart from being the wrong application, it will not ride very well. Without knowing this, you may be tempted to rebalance the tire/wheel assembly, when the problem is actually misapplication. Be sure to research your choice of wheels before selling a customer on a particular style. Most wheels are not available in 5-115 mm with medium offset yet.
More application issues exist, and more are sure to come. Always dry fit aftermarket wheels to the application before mounting. Any combination of these problems can turn a potential profit into a bad situation.
If you are struggling with a fitment issue or ride complaint, feel free to send me an e-mail or call. In many cases, myself or one of my colleagues has dealt with the same problem, and one of us may be able to provide a clear answer.