Bought a 2015 Volvo VNL about a year ago with 480k miles it’s now at 560k. So far I’ve had to replace the crankcase pressure sensor and radiator hoses after they busted while going up AZ mountains. After replacing them I started an having oil leak that I have not fixed yet I’ve just been adding oil as I drive. I’m wanting to know, what are some preventative maintenance things I can do to preserve and renew the life of my truck? Will replacing timing belt be enough or is there more to it? I want to repair my oil leak and reinforce my truck to make sure it’s healthy and last long. I’m new to owning my own truck so any knowledge is greatly appreciated.