You can also hover your mouse to the upper left corner of your monitor to open the menu, and change the friction settings if what you are looking for is more grip on a specific terrain surface
Thanks for all but I want to know where is the grip and height comand lines in the truck file because I take exemple of files that I have to create my own truck file.
Thanks for any reply.
Friction is modified using set_node_defaults as georgy pointed out. Height can be adjusted, poorly, using precomp in the shocks section or by editing the geometry of the N/B.