Multi grade oil in a detriot diesel ??

[Timbercruiser]

I talked to a cutter today been running a 353 detroit for 30 years he puts 10w 30 in in the winter he said he did that for ever. Never had engine problems at all. Another old bush mecahanic told me multi grade was fine and he fixed many many detroits. So i guess its ok anyway to run multi grade oil in my 353 ?? I still have 30 wt in her and run the propane heater and it fires up fine ??

[barbender]

I think the one thing you will find consensus on is that you want a low ash content.