How to pull wheel bearing hubs – the right way.
Since the late 90s, wheel bearing hub assembly’s have been used on each wheel of most vehicles. Unlike traditional wheel bearings, which can be taken apart to repair individual components, when a wheel bearing fails in a hub assembly, the entire hub is taken off the vehicle and replaced.
Wheel bearings are either pressed or bolted together as a "wheel hub and bearing" assembly. Unfortunately, as vehicle manufacturers begin cutting costs and using lightweight metals such as aluminum in more places on the vehicle, pulling the old hub and bearing assembly off has become a nightmare on vehicles that utilize this type of bearing, especially in the rust belt (or salt belt).
As with most time-consuming and frustrating repairs, the demand to provide technicians with a more productive solution has grown with replacing wheel bearing hubs and assemblies. Here are a few tools & techniques that technicians are using today to remove pressed in wheel bearing assemblies.
1. Slide hammers
Slide hammers have been around for years, traditionally being used for removing seals or popping out dents. Tool manufacturers have adapted this tool by creating a plate that attaches to the studs on the wheel bearing assembly. It’s a slick tool that takes almost no technical skill to use. In many cases, the 30-pound weight that rides the steel rod has enough force to pop out wheel bearing hubs. However, in cases where a steel wheel bearing hub is pressed into an aluminum housing (knuckle), especially in areas with harsh winters that use road salt for de-icing, a chemical reaction occurs that causes massive corrosion, fusing the components together. In these cases, a slide hammer will rarely provide the force necessary to pull the wheel bearing from the knuckle.
2. Hammer bar
A large steel bar is bolted onto the wheel bearing studs, then the technician uses a sledgehammer and smacks the steel bar until the hub comes out. Again, the only skill required to use this tool is the ability to swing a big hammer. This can be a quick and effective method on many vehicles; however, it is attempting to walk the bearing out at an angle. For many makes and models, the wheel bearing that is pressed in is completely flush with the housing (rather than tapered as it goes in). Using this method on such a bearing assembly will either prove ineffective, jamming the bearing in place or cause damage to the knuckle, resulting in further repairs and costs to the customer.
3. Hardened bolts
Some technicians have perfected a rather simplistic method of extracting wheel bearing hub assemblies from vehicles which have seized components. First, the technician will knock the studs out of the wheel bearing and will place a hardened bolt into it (towards the steering knuckle), with a nut on each side of the hub. Next, the tech will work the hardened bolt by hand, pressing the hub out of the knuckle mechanically. This method can be cheap and effective; however, most dealerships will bill between 30 minutes to an hour and a half for this repair. This method can take up to an hour and requires extensive energy. In addition, the hardened bolt takes a beating and is only good for one use.
4. Hydraulic press
A last resort for some technicians, especially those in the salt belt, is pulling the entire knuckle off the vehicle, placing it in a hydraulic press and pushing the hub assembly out. This method is highly effective, yet incredibly time-consuming. In addition, when a steering component such as the knuckle is removed, realignment is necessary. This means added shop time and costs to the customer.
This wheel bearing puller bolts right onto the wheel hub flange, then three unique push rods exert a tremendous amount of force, removing the wheel bearing hub. The Tommy ProKit from ProMAXX Tool is engineered to triangulate and distribute the force necessary to remove the most stubborn, pressed-in wheel bearings, without having to remove the control arm. The tool takes some assembly the first time it is set up. After set up, the technician will only have to shock the hub with an air hammer, then use an impact wrench to turn a center bolt which contracts two steel plates, pressing the pushrods against the knuckle (not the axle), and pulling the hub straight out. This is essentially the exact reverse of way they are installed.
Currently, the Tommy ProKit is available for the Ford Explorer, Edge and Taurus, as well as the Subaru Legacy, Impreza, Outback, Forester and Crosstrek, with more models on the way. To learn more about the Tommy ProKit or to order yours today, check it out online or call ProMAXX Tool at 724-242-6788.