toy4x4runner
1/2 ton status
can you run 15W-40 "diesel" oil in a gas motor? Other than it keeping the engine squeaky clean will there be any issues? I'm running 10W-30 Mobil1 right now and am thinking about switching to Amsoil 15W-40 Diesel oil.


CyberSniper said:If the motor has had ****ty oil in it for its entire life then putting in an oil with a lot of detergents in it (diesel) will cause the ****ty oil's deposits to break loose. In those deposits is usually everything from dirt to carbon to old bearing material... which when released makes real good abrasive material... and tends to plug up things like rod bearing passageways and lifters.
A good place to look for deposits is on the high side of the head under a valve cover. It'll also be all over in the valley.
If you want to clean a motor out and let all that crap loose, dump a quarter of ATF in 15 minutes before you change the oil. I've gotten "floaters" out of motors with only 20,000 miles on them.
Yes, 5W-30 in a Ford Powerstroke.... The main reason is that the injectors in the Navistar engines are hydraulically actuated. It's the HEUI system and Cat also uses it on some engines. the slightly thinner oil seems work a little better with this system.toy4x4runner said:well I was at Amsoil's site and they "reccomend" 5W-30 Diesel oil for the powerstroke fords! I coudn't beleive it... 5W-30 oil in a turbo Diesel. I think my 10W-30 Syn Mobil 1 is better than running dino 15W-40. I'll stick with my 10W-30 syn.
Yes you can, I have ran 15W-40 diesel oil in multiple gas engines and it works just fine. The oil is just over kill, thats all.toy4x4runner said:can you run 15W-40 "diesel" oil in a gas motor? Other than it keeping the engine squeaky clean will there be any issues? I'm running 10W-30 Mobil1 right now and am thinking about switching to Amsoil 15W-40 Diesel oil.