Goodparts CVJs - Winter Work - '08 & '09





CVJ Plunge Reserve Test

Now that the axles and differential were all installed it was time to make sure there was sufficient reserve range of movement. This consisted of raising the hubs up against the upper bump stop, taking some measurements, and then lowering everything and taking some more measurements. If you still have lever shocks, the test is different from the one I did.

The directions tell you to use a jack to raise the trailing arm up until it hits the upper bump stop, but after doing it this way I found that I could just lift it to that position.

The jack was needed to hold it in position.
Touching the upper bump stop.
I unscrewed the axle nut to the last thread and measured from the washer to the nut.
I had 3/4" and then I pushed the whole axle in to check the plunge depth.
As you can see, the nut is now against the washer so I used the whole 3/4".
You need a minimum of 1/2" of plunge range.

That tested the plunge reserve range at the top of suspension travel. Now you have to test the bottom reserve range which is done a little differently. Tighten that axle nut down again and make sure your shocks are also tightly secured to their mounts. Now you let the hub assembly drop to the bottom of its travel as determined by your shocks. When I did the left side I discovered where my annoying squeak was coming's the left shock.....and for the past year I've been blaming the Nylatron bushings. So, of course, this resulted in a shock upgrade and the Blind Moose conversion kit. That's being documented in another section of my site.

The hub has dropped as far as the shock will allow it.
The bottom red arrow showsthat the shock is still attached to the Trailing Arm
Now you measure from the center of the axle to the floor.
BTW.... this little level is a must have for hanging pictures with two hooks!

Now that you've taken the first measurement, remove the bottom nut that holds your shock to the trailing arm and let the assembly drop by itself as far as it will go.............DO NOT manually force it down or try and get it to drop more after it stops. You can damage the CVJ if you do.

The arrow shows that the shock is not longer attached and
the whole assembly has bottomed out.
Now you measure again and determine how far the axle has dropped. The difference
between the two measurements is your plunge reserve range at the bottom

The instructions call for a reserve at the bottom of 1" but I only came up with 1/2 - 7/8" depending on how I had the hub rotated. You actually rotate the hub and take a few measurements. I emailed Richard and he wasn't overly concerned with the bottom reserve as it only comes into play if you have the car jacked up and the shock disconnected which would force the assembly down to the full extent of its range......... or maybe if you like to fly over hill crests and get airborne!! The top reserve is the more critical one as you are more apt to bottom the car out and hit that top bump stop. Plus..... the Blind Moose conversion and new shocks may change the I'll be doing this all over again in another week or so.

First Test Drive is next!