[mikeymike]

I have the volvo D12 motor. I have @610K on it now. After having it serviced the dealer said I should probably have the valves adjusted. Not because they heard or detected something just since I have had the truck it has not been done . Anyone else have this done or not done?

[solo379]

Don't know about D12, but i do it every 150,000 miles, on my CAT.

[uncleal13]

Check the engine owners manual. I found a VHD operators manual on the internet, it says every 12 months or 2,000 hours. I have a Mercedes, my manual says first time at 60,000 then every 100,000 after that.