Can I Use Diesel Oil In A Gas Engine?

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
My bud puts diesel oil in the crankcase of his Caddy 472. He says it stands up to pressure better and has zinc in it. Is he full of you know what?
I was under the impression that zinc in oil isn't that big a deal, no?

Any downside to using diesel oil instead of conventional?



use of that oil in a 1970s something caddy v8 won,t hurt anything ,
as long as its the correct viscosity and changed at about every 12k-15k miles or less
zinc helps reduce lifter and cam lobe wear on flat tappet cam engines,
wear that is not a big factor in engines set up with roller lifters
and yeah there are more modern oils with better additives,
and some oil is designed to better handle e85 and similar issues diesel oils won,t be set up to handle,
but if thats the biggest potential mistake he ever made hes home free

https://www.machinerylubrication.com/Read/28576/comparing-gasoline-diesel-engine-oils-

If you have an old, classic car that uses a flat tappet camshaft, it is recommended you do run it. It contains higher amounts of additive ZDDP, which bonds to metal and provides a sacrificial wear surface in high stress environments such as a cam lobe against a lifter. The ZDDP is stripped from the cam lobe instead of the cam lobe material itself.

This will prolong cam life in such a hostile environment. ZDDP used to be an additive in conventional oil for gasoline/ petrol engines, but due to emissions regulations, the allowable amount of this additive has fallen below the requirement for older flat tappet engines. Modern roller lifter/follower engines do not care, but flat lifter cams will wear fast without it.
people typically do this all the time, as long as its the right viscosity for the engine… which is mentioned on oil fill cap or if unsure, check out the owners/service manual. Diesel oil has a lot more detergents so, it will clean out a gunky, sludged up, dirty motor internally, very well. Oils such as Delo 400 or Rotella T, in an effort to save money $, is always few bucks cheaper then any gasoline motor oil, and is rated for use in both Gas and diesel engines. Its not ideal for reason said above but it will work fine. Diesel oils, They're referred to as mixed fleet spec. Oil, because its dual purpose oil. A lot of guys with older pushrod ohv engines love diesel oils, especially v8s with flat tappet cams, because its got plenty of zinc in it, so the cam won't go flat

https://blog.amsoil.com/can-i-use-diesel-oil-in-my-gas-engine/#:~:text=Yes, you can use diesel,viscosity requirements of your engine.&text=For the typical gasoline application,for both performance and value.

https://www.api.org/products-and-se...ations/oil-categories#tab-diesel-c-categories
https://www.api.org/products-and-se...d-classifications/oil-categories#tab-gasoline

keep in mind you could easily mix a couple quarts or 3-4 of fully synthetic oil like Valvoline with.
a couple (2-3 quarts) something like SHELL diesel oil.
and have even better lubrication with the benefits from both types


http://garage.grumpysperformance.com/index.php?threads/which-oil-what-viscosity.1334/

http://garage.grumpysperformance.co...ilter-you-sellect-does-make-a-differance.117/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.com/index.php?threads/only-approved-specific-oil-can-be-used.16302/

http://garage.grumpysperformance.com/index.php?threads/viscosity-centistoke.15612/#post-93303

http://garage.grumpysperformance.com/index.php?threads/bearings-and-oil-flow.150/


http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/

http://garage.grumpysperformance.com/index.php?threads/new-mobil-1-annual-protection-oil.13331/

http://garage.grumpysperformance.com/index.php?threads/oil-filters-related-info.2080/
 
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