The C5 Corvette is an amazingly well engineered machine. It needs nothing from the factory, and for most folks, the car only needs routine maintenance or replacement of items as they begin to push 20 plus years of age. However, raise the performance ceiling a bit, and you start to find new limitations. One such limitation folks start to encounter early with Autocross, Track and Drift, is the OEM wheel bearings. As soon as you introduce frequent and more significant braking forces or introduce lateral loads beyond what was possible when the cars were released (see the progression of 200tw tires and lap times), the wheel bearings on the C5 Corvette quickly become a point of failure, and we don't need to tell you how dangerous having a wheel fall off is.
Don't just take our word for it though. Here's a picture of the near catastrophic wheel bearing failure of our author Shred Jesse's 1999 C5 Corvette time attack Corvette. As you ca see, it developed a crack radially along the wheel bearing. By the time Jesse caught it, only 1/3 of the wheel bearing was holding the wheel on!
So what's a C5 Corvette owner to do? If you've replaced a wheel bearing already on a C5 Corvette, you know you don't want to be treating this item as a rapid consumable due to the involvement of swapping them out. While the job is well within the wheel house of most driveway level mechanics, there's still a decent chunk of time involve in pulling everything apart. So when it comes to wheel bearings you're going to want a one and done solution ideally, especially since if it does fail mid-event, the consequences can be lethal.
There are a lot of aftermarket parts store options such as Moog and the like. These... are not recommended for anyone whose Corvette is operating above the stock level of the original state of their car. These parts store wheel bearings just don't last and are really meant as a street going replacement. What you want is an upgrade.
There is the option of the SKF X-Tracker wheel bearing. These are renowned for their durability and have been tested at the highest levels of racing with C5 Corvettes... but at $1600-1900 a set, they're a fair bit of money out of pocket.
Enter: Mechanical Power (MPI) and Their Wheel Bearing for the C5 Corvette. MPI has been making bearings for half a century and counting. They recently decided to pop on over into the C5 Corvette market with a better priced and equally if not superiorly robust solution to the current offerings. At $249 a wheel bearing, a set of 4 of these will run you just under $1000, which at nearly half the price of a set of SKF X-tracker wheel bearings they're worth stopping to consider.
Now well informed C5 Corvette owners will know that MPI has had C5 Corvette offerings for a few years now with their Gen 1 and Gen 2 offerings. Our author Shred Jesse actually got on some of the original bearings and has been helping field test them on his White C5 Corvette, and still to this day runs the MPI Gen 1 wheel bearings on the rear of his C5 Corvette. The bearings were good and for most users functional, but Shred Jesse and others racing the MPI bearings exposed where they product could improve. MPI took the feedback, reviewed where they could make improvements, and developed their Gen 3 bearings.
As luck would have it, we've been building up the chassis of our Dead to Shred C5 Corvette for hitting the track, making our car a perfect test mule for the new MPI V3 wheel bearings. We reached out, received a full set of MPI Gen 3 bearings for testing, and here's what we found.
Visual Comparison of the MPI Wheel Bearings to OEM
Here's a side by side shot of the OEM wheel bearings next to the MPI Gen 3 wheel bearings. If you can't already tell, the MPI is notably stouter. Besides the nicer finish, the wheel studs are also increased in length to accommodate larger aftermarket wheels along with easier wheel changes in general.
If you really want to see how much more stout the wheel bearings are though, look at the two of them from a side on view. The MPI has nearly twice the hub thickness of the OEM wheel bearing, which then quickly flanges to be even thicker. These are truly impressive pieces of kit!
Track Tested & Abused
Now what's a good product review of a product that's meant to take some serious abuse without some serious abuse? We bolted the MPI Wheel Bearings on and threw a ton of different drivers, disciplines and tracks at them. From several rounds of autocross and an open track day with 5 different drivers shredding the car (all before we even had ABS figured out) to another open track day calling, we put the MPI V3 Wheel bearings Corvette through it's paces!
Above is our Dead to Shred test mule C5 Corvette at a WMC Autocross event. This event was just after restoring ABS but before we had fully added aero onto the car. Two different drivers of two different skill levels took to the course and put down good times for both of their respective categories, along with finishing with the fastest Corvette of the day!
(Insert ORP picture with white Corvette chasing it)
We also hammered on the car at not one but TWO open track events at ORP with multiple drivers. This not only meant the car endured 3-4 events worth of seat time, it was done back to back to back with little time to cool down between drivers. With some seat time and solid configuration on the car Shred Jesse was able to run just 1 second behind his Time Attack C5, which is both insanely impressive for a largely stock car and VERY abusive. We were also able to get one of our other intermediate level testers down to a sub 2 minute lap time at ORP, the barrier to break for most drivers out there.
Now like we said, we drove the pants off of this car. In fact, we drove the Dead to Shred Corvette so hard and for such extended durations that we cracked the 14" solid front rotors! That just goes to show you how much heat and abuse we put into the chassis of this car, with the MPI Gen 3 wheel bearings literally right in that area enduring the same heat and stresses.
So how did the wheel bearings stack up to the abuse?
Pulling the Grey Corvette back onto the lift after the event and checking for bearing play, we found not a thousandth of deflection in the wheel bearings. The ABS sensors are holding up great as well, and we're well past the point where OEM bearings would have failed us as demonstrated by the cracked brake rotors... and yet the MPI Wheel Bearings are still trucking along!
After years of testing and product refinement, we think MPI really got their details right and have put together a product that unseats the SKF X-tracker. We'll be running these on our Grey Corvette, and we'll keep you all updated if anything changes... but thus far we'd be real surprised if these weren't in it for the long haul!
Check out the MPI Gen 3 Racing Performance 30 Spline Brake Hub Assembly on their Website
For folks running upgraded axles or running C6 Corvettes, check out the Gen 33 Spline Hub Version.
