Finding the correct hubcap, axle cover and lug nut covers for your semi truck can be difficult, but it doesn’t have to be. Here are our tips for measuring the wheel to determine what you need before you buy.
When finding a hubcap for the front (steer) axle, first count the number of notches. Notches are sometimes also referred to as pilots. We offer many universal fit front hubcaps that fit wheels with 4, 5, and 6 uneven notches. There is usually no need to measure the diameter of the opening, all semi trucks have a standard 8-23/32″ diameter center hole.
Next measure the lip height. Most aluminum wheels have a 1″ lip and most steel wheels have a 7/16″ lip, however it is always best to measure to be 100% certain before buying. We also offer a universal fit front hubcap that will fit both sizes.
Choosing a hubcap for the rear (drive) axle requires a bit more measuring to be sure you get the perfect fit. First, measure the diameter of the axle.
Next, measure the stud size. Common sizes and quantities are 8 of 5/8″, 8 of 3/4″, and 12 of 1/2″ studs. A Dana Spicer hub has eight 5/8″ studs. A Rockwell hub has eight 3/4″ studs, some may also have one flat bolt instead of a stud. If the wheel has eight 5/8″ studs it usually uses an 8″ hubcap. If the wheel has eight 3/4″ studs it usually uses an 8-1/4″ hubcap. If the wheel has twelve 1/2″ studs it usually uses a 7-1/2″ hubcap.
One more thing to consider is the stud length. If the wheel has extra long studs you will probably need a hubcap with a 1-1/2″ lip.
Now let’s find lug nut covers to complete the look. First, determine the size of the lug nut by using a socket that fits snugly. The size marked on the socket is the size of lug nut cover you will order. Some lug nuts have a flange or washer where it meets the wheel, others do not. Be sure to read the product description while shopping online, we offer covers for lug nuts with and without a flange. 33mm lug nuts usually have a flange and are commonly found on trucks 2006 and newer. 1-1/2″ lug nuts are often found on trucks older than 2004. If you do not have a metric socket set, you can make a educated guess as to your socket size using standard measurements. 33mm is smaller than 1-1/2″, it converts to 1.29″.
We offer both push on and thread on lug nut covers. Thread on nut covers require at least a 1/2″ of stud thread to secure properly. Use push on nut covers if the wheel has less than 1/2″ of stud thread protruding beyond the nut.
More options include axle covers (also called top hats), oil cap covers, aero covers, wheel simulators, and wheel covers. Here at Iowa 80, we have an extensive variety to choose from, so let’s start shopping!