Debate: Should you warm up a diesel engine before driving or just send it?

I've been going back and forth on this with my buddy Mike from the shop. He says letting a cold diesel idle for 5 minutes before moving is non-negotiable, especially in winter temps below 30 degrees. But I've been just firing up my 2005 Duramax and driving gently right away for the last 6 months with no issues. Which side are you guys on, and do you have actual proof one way beats the other?

2 comments

2 Comments

sam_rivera1mo ago

Five minutes minimum in cold weather sounds about right to me Mike's been doing it forever and knows his stuff.

skyler_kim151mo ago

Oh man, give it five minutes and you'll be out there shivering while the engine's barely warm. Guess Mike never had to jump-start a cold truck at 6 AM like the rest of us. But hey, I'll trust the guy who's been doing this since before hoodies were invented.