HOWTO: Replace your Coilover Bearings

Someone recently asked me for the list of what I've got stacked up on my top hats, and I couldn't for the life of me remember exactly what was there. Today, after doing this maintenance, I took a picture to show my setup. I've got a large washer on top, followed by a thin bearing race, a needle bearing, a thick bearing race, another needle bearing, and finally another thick bearing race.

Here's what it all looks like.

Here are the steps involved in replacing the top bearing on your Ground Control (or equivalent) coilovers. Note that you've only got bearings in the front since the rear struts do not rotate.

If you're getting creaking and popping noises from your front springs when you turn, then chances are that you either don't have proper bearings there or something is causing them to bind up so they can't turn properly.

If you've already got all the proper parts in place, you may just need to lift the car up and clean and lubricate them. If not, then this page may help you to find what you need and get it installed.

Over the years I've been running with Ground Control coilovers, I've tried to deal with the binding issue in several different ways and all have worked to some extent but ultimately failed. My current iteration however appears to be working well. I will give the details on this in a moment but for the most part, this page is here to give you the source and the specs for getting new bearings if you need them.

Originally, GC provided very thin bearing races (machined, hardened washers) with their kits but on a somewhat recent install, I found that they've since replaced them with thicker ones. I actually recommended these years ago on j-body.org so perhaps they were listening or maybe they came to the same conclusion on their own. Either way, if you have an older kit with the thin races, it may be a benefit to you to replace them. At the same time you can add a second bearing, as I have, and hopefully eliminate the binding issues entirely.

The main purpose to this page is to provide the specs on what to order. They can be found on j-body.org here but it takes some searching. With this page, it should remain easily accessible to all.

I ordered mine from Motion Industries and they were a pleasure to deal with.

These are the specs on what you should order:

Bearings (You need 2)

Description: NTA-1423, UNSEALED, 
THRUST BEARING
MFG Part #: NTA 1423 BRG
Manufacturer: TORRINGTON BEARING CO.

SHAFT DIAMETER (BORE): .8750 IN.
OUTSIDE DIAMETER: 1.4375 IN.
WIDTH: .0781 IN.
CLOSURE TYPE: UNSEALED
TYPE OF NEEDLE BEARING : THRUST BEARING

Races (You need 4)

Description: 
TRC-1423, UNSEALED, THRUST WASHER
MFG Part #: TRC 1423 THRUST RACE
Manufacturer: TORRINGTON BEARING CO.

SHAFT DIAMETER (BORE): .8750 IN.
OUTSIDE DIAMETER: 1.4375 IN.
WIDTH: .0920 IN.
CLOSURE TYPE: UNSEALED
TYPE OF NEEDLE BEARING : THRUST WASHER

I would add to this at least one large washer that will fit snug in the opening at the bottom of the strut mounts. This prevents some lateral movement of the strut assembly and allows the bearings to maintain a flat surface on which to make contact and rotate.

As for the actual replacement, this is quite simple.

1. Start by loosening, but not removing, the top nuts from the struts. Use an impact wrench on the lowest setting that gets them loose. If you spin them right off, just put them back on by hand without tightening them down.

2. Now lift the front of the car up. If you lift both sides the suspension will drop further down making it easier to access the bearings. If you intend to do this, however, ensure that you break loose the lug nuts first since once both sides are raised, the front wheels will turn freely making it difficult to loosen them.

   Check your manual for the proper lift points for your car and always make sure the car is properly supported by jack stands when working underneath it.

3. Remove the front wheels.

4. Remove the top nuts from the struts. This should be easy since you loosened them in the first step.

5. Now you can reach up and grab the top hat on top of the spring and pull the strut rod down. Pull it down enough that you can lift the top hat and bearing assembly up over the top of it. Be careful not to drop any of the pieces.

6. Now use some solvent (brake cleaner works wonders) to clean off the existing bearing and races. Inspect the parts for any wear or damage and replace as necessary. Add a healthy dose of WD-40 (bicycle chain lube is even better if you have any but don't use grease) and put them back on.

7. When putting them back on, be mindful of the order of the parts. At the very least, from top to bottom you should have the following pieces:

   • Thick washer provided by Ground Control.

   • Bearing race.

   • Bearing.

   • Bearing race.

   • Top Hat

   • Spring

   On my setup, however, I've added a little extra. Under the washer that Ground Control provides, I've added one or two larger washers that are about the same diameter as the opening in the bottom of the 00-05 strut mounts. These fit flush into the opening and prevent lateral movement. Then I have my original thin bearing race followed by the original bearing. Under that I've got the new, thicker, race followed by a second bearing and then another thick race. Under all that is the top hat followed by the spring. This setup adds around 10 mm to my overall ride height, but this is nothing that can't be adjusted for with the perch. This solution has resulted in no binding at all in the past few months despite driving through enough heavy rain to remove all of the lube I had added. This doesn't mean you should still clean and lubricate them every few months (they're open to the elements and collect dirt) but it seems to be a good sign in the quest to eliminate top hat binding and the embarassing noises that come with it.

8. Now work the strut shaft back up through the strut mount and put the top nut back on. You don't need to be concerned with tightening it down right now. You can do that with an impact wrench once the car is back on the ground.

9. Put the wheels back on and torque the lug nuts appropriately. If you've got both sides off the ground, you can just tighten them down and torque them properly once one side is making enough contact with the ground to keep it from turning.

10. Lower the car back to the ground.

11. Tighten the top nuts on the struts.

That's all there is to it. Since you didn't remove the struts from the car, and there is no adjustment where the strut shaft goes through the mount, you will not need an alignment after this procedure. If your alignment was good before you started, it will still be good when you're done.