I have a GT mountain bike which is about 15 years old. The bike is generally in good condition and works as a great commuter tool and casual rider. The only problem I have is that the suspension forks appear to have play in them. When I apply the front brake there is a juddering; not from the vertical movement which appears smooth but from within the fork sliders as though there is excessive play somewhere. I'd like to strip the forks to investigate but not sure if thats possible.

I've taken a few photos and wonder if anyone could help?











The nuts at the bottom of the forks come off to expose a threaded section and I assume that the black plastic top cap should unscrew in some way. I've seen a strip down video on YouTube on a similar set of forks but wondered if mine are in fact serviceable. Bit loath to strip down without advice as I need the bike for daily use.

Would appreciate any pointers. Many thanks.