1994 Mazda MX-5 Miata: Preventative Maintenance
June 01, 2010
Not unexpectedly, Project Miata has some worn-out underpinnings. Old cars are like that.
It could be argued that this oozing tie rod end is still serviceable -- hey, there's no real play in the joint, and the grease is... well, there's still grease left. But we'll use this image as a good excuse to swap 'em out with new tie rod ends from the LE / R-package cars. Slightly longer (and a whole lot fresher) than the stock Miata tie rod ends, these will reduce bump steer somewhat on our lowered car and lower the blood pressure of our Risk Management department staff.
Other preventative maintenance we'll tackle at the same time: upper control arms and new wheel bearings.
What's up with the control arms? During the suspension overhaul, I noticed that one of this car's front upper balljoints has about 1/16" of axial play. And you can hear it rattling when you drive it over rough pavement. Since Miatas have their upper front balljoint integrated into the control arm, they're not serviced separately -- you simply buy new control arms when the balljoints go bad. On the plus side, the new control arms also come with fresh bushings.
A sticky-tired Miata that's driven hard (particularly on a track) will go through wheel bearings faster than do many other cars. As such Spec Miata guys are fastidious about their replacement even though they repack their bearings with high-temp synthetic grease.
Our bearings are very likely original and if so have 176,000 miles on them. They're not roaring, but Miata wheel bearings can be totally shot and not make noise. Also, determining a bearing's health using the ol' grab-and-shake-the-tire technique doesn't always work on a Miata for some reason. What you do get just before the bearings are ready to completely self-destruct is crummy turn-in and accelerated tire wear. So, while we're in there...
Jason Kavanagh, Engineering Editor at 176,429 miles.