I sometimes find myself in the middle of oddball arguments. The most recent one was about wheel fasteners, specifically whether wheel bolts were better than wheel studs for affixing the wheel to the hub. The discussion was with a technician who has spent a large part of his career working on only European vehicles. European vehicle manufacturers use wheel bolts, while all other manufacturers use wheel studs and nuts. Having worked as a Honda technician early in my career, I prefer studs and nuts. He was naturally in favour of the wheel bolt. Without having done any actual research on the subject, we were both just expressing baseless opinions, so I decided to investigate the differences, and which one is better to further support my argument.
It is well established that the use of wheel bolts was made mainstream by German auto manufacturing. The most common theory as to why is cost and manufacturing simplification. A European vehicle only requires a mounting hub and a bolt, while all others require a mounting hub, stud, and a nut. Essentially, there are two parts that need to be designed for European vehicles while three are required for everything else. Expanding this further into manufacturing costs, five studs per wheel for most applications, multiplied by four wheels equals 20 studs per vehicle. While 20 extra studs may not seem like a lot, it certainly adds up over the hundreds of thousands of vehicles produced.
From a clamping force perspective, both offer similar results. However, a stud with a nut has superior accuracy when torquing because only the nut is being turned on a single axis. It is for this reason that most sensitive engine parts such as head bolts are replaced with studs when any kind of serious performance engine work is being completed.
The key advantage of using bolts is obviously cost. But a couple of other minor pluses are weight savings and the ability to easily change out to longer bolts should you wish to try on different wheel packages. For the end user, these two minor advantages just don’t seem significant enough, especially when you consider the biggest negative: When the threads are damaged on the wheel hub of your European car, you’re probably in for more than just a hub replacement. The hub is usually integral with a wheel bearing, which means a costly hub and bearing replacement. Damage the studs on your North American vehicle and it is a far easier repair; just disassemble the brakes and knock out the damaged stud, and replace with a new one.
Oddly enough, many European car owners who are track enthusiasts will upgrade their wheel fastener system to a stud and nut system immediately after their first trackside incident. This usually occurs when they accidentally cross-thread a fastener while attempting to do a rapid tire change over.
The advantage goes to the European manufacturer for their upfront cost savings, but the customer takes the hit when any problems arise. Changing your flat tire at the side of the road? Well, the wheel stud wins by a large margin. It’s much easier to align and install your wheel on studs, rather than fussing around trying to line up the hub, rotor and wheel, all while supporting the wheel with one hand and trying to get the bolt started with the other. Stud and nuts for the win, in my humble opinion. Who’s with me on this?
Your automotive questions, answered
Thanks for the article about trailer bearings. I have a light trailer that I use to move a sailing dinghy a few times per year. The trailer is stored indoors and is never submerged, the only time it gets wet is when it’s out in the rain. In a heavy year it will get driven around 1,500 km and 300 – 400 km in a light year. The trailer is of the flat bed variety, open square frame with two sets of wood felt covered bunks on it. It weighs around 250 pounds with a capacity of 700 pounds.
Could you let me know how often I should have the bearings serviced, once per year seems a little high given the low usage.
Thanks in advance for your help.
Most axle manufacturers recommend a bearing repack service interval of once per year, or 12,000 kilometres, whichever comes first. Boat trailers that are submerged regularly require much more frequent servicing.
The problem when offering automotive advice on this scale is how to best observe manufacturer guidelines. If I offer advice that counters a manufacturer, and some reader has a catastrophic wheel separation failure because of that advice, then guess what is going to happen?
I appreciate your situation, but there is no perfect answer, Jeff. Unfortunately, trailer bearing maintenance is often neglected, relegated to the realm of “it’s never been an issue before, why should it be an issue now?” That is of course, until you are the one stuck at the side of the road scratching your head, wondering how you are going to get your broken-down trailer home. All I can do is provide industry standard guidelines, and then you must make the decision that is right for you. Happy sailing.
My sensors on my Dodge are set for 80 lbs. in the rear and 65lbs in the front tires. That is too much. The sticker for the truck says 65 lbs. in the rear and 50 lbs. in the front. How can I change the computer to those figures? The Dodge dealer said I must have a 4-digit code to enter in the computer. Where do I get the code? Dodge was no help in this matter.
Firstly, I assume we are talking about the Tire Pressure Monitoring Sensors (TPMS) on your full-size Ram pickup truck. I am missing some critical piece of information here Lisa. Code or no code, I am unaware of any way for you, as a consumer, to be able to go into your truck’s computer and reprogram tire pressure information. This would strike me as a huge liability for Chrysler, especially if you could just randomly change tire pressure minimum settings. Therefore, I am not sure what you are asking. My only advice is to go back to the dealer and re-explain your situation and hope for some resolution to come to light.
Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail email@example.com, placing “Lou’s Garage” in the subject line.