When I get in higher RPMs, I hear a rattle/vibration in my 4x4 manual shift lever. When it's vibrating I can put my hand on it, and it stops. I took the boot off and checked under it and also checked underneath the truck, I couldn't find anything loose.

This is the only link I found commenting on this issue:

http://www.f150online.com/forums/tra...ift-lever.html

Anyone else have this problem? Know how to fix it? I'm not really sure what the extension housing is mentioned in the article.