Over time all CC-01 suffer from this: the steering rod that goes through the chassis wears out, adding a lot of play to the steering. This makes the handling of the car very unpredictable, even at modest silver-can speeds.
To fix this one can either do a DIY repair job as described in https://www.tamiyausa.com/articles/feature.php?article-id=499. or use a simple to install repair kit from GPM Racing Products. For us the GPM kit was the better route as we would otherwise have to buy parts for the DIY solution.
The GPM kit arrived without instructions, but it is pretty obvious how the parts go together. The craftsmanship and finishing of the parts is very good. You need to reuse the ball ends from the existing steering assembly in your CC-01, but all other parts are included.
This picture shows the main shaft that connects the servo with the bell crank assembly through a long tube in the CC-01 chassis. The white bushings contain ball bearings so that wear should no longer be an issue.
Note that in the picture above the bushings are reversed: the taller bushing needs to go to the bottom of the chassis where the bell crank is (right side in the photo), the thinner bushing goes where to the top where the servo connects (left side in the photo).
The bell crank pre-assembled. The original Tamiya bell crank is in the background. The ball ends still need to be transferred to the new piece. Note that since we are dealing with metal-on-metal it is advisable to secure them with blue Loctite during assembly.
The lower bushing installed. One can easily press it in with the thumb.
The bushing on the top fits as well as the bottom one: nice and snug.
The bell crank has been installed and secured. Now all that is left to do is reassemble the front suspension.
Top view of our CC-01 with the GPM steering kit installed.
From the bottom not much can be seen as it is covered by the skid plate.
The GPM steering kit worked very well for us. The slop in the steering is now drastically improved, the only slop left is in the ball ends. The car is now much easier to control and while there is still a bit of bump steer, caused by the over-all suspension geometry of the CC-01, it is tolerable.
Now our CC-01 Unimog is fun to drive again!