Diesel oil in gas engines

[Egon]

Some of the new gas engines are getting a little more particular with the type of oil they require.

 

[Eagleview]

We use Castrol RX Super 15W40 in everything we own (even the hydraulics)but dont have the cold weather you guys get . As stated earlier Diesel oil has more detergent in it to cope with the soot , it will cause no harm in a petrol engine . But do not use it in a Propane engine . Propane has an acidic by product that attacks the white metal on engine bearings . You must also not use normal petrol engine oil in a Propane engine for the same reason . I have seen bearings stripped of all white metal within 25,000 miles . You must use an oil such as Penrite HPR Gas to prevent bearing failure .

 

[DieselPower]

There are a large number of engine oils that are multi API rated for use in S and C category's. One thing to watch in automotive applications is the viscosity. Many modern gas engines use viscosity's as low as 5W20. Using a 15W40 viscosity oil is going to effect your fuel economy. Using one oil for all isn't a problem if done with a little common sense. Personally I use two different viscosity oils. 15W40 for my tractors, small engines (lawn mowers/tractors), diesel P/U and older gas engines in cars. For my more modern gas engines I use 5W/30.

 

[RickB]

Many current S-rated engine oils have REMOVED zinc and other trace ingredients for modern engines/emissions standards. These oils are actually WORSE for older solid lifter spark ignition engines than older oil technology S-rated oils or current diesel rated engine oils. Current advise is to use S rated oils on modern gassers but stick with a c-rated oil of the proper viscosity for diesels and solid lifter gassers.

 

[RWEST]

Many current S-rated engine oils have REMOVED zinc and other trace ingredients for modern engines/emissions standards. These oils are actually WORSE for older solid lifter spark ignition engines than older oil technology S-rated oils or current diesel rated engine oils. Current advise is to use S rated oils on modern gassers but stick with a c-rated oil of the proper viscosity for diesels and solid lifter gassers.

Ahh, yes, the "ZDDP" controversy. Much discussion/debate ongoing. Supposedly, the new CJ-4/SM iteration is okay as regards valve-train wear, with boron, and maybe something else, replacing the lost zinc/phosphorous, but I think the jury's still out on that one. There seem to be way too many cam issues reported, primarily among gassers running SM rated oil, to blame it ALL on faulty cam or lifter construction, as some seem wont to do. I mean, if an engine that's worked fine for 20-30K miles on SG/SH rated oil suddenly wipes the cam after a change to SM, I'd be looking at the oil, not the cam.

Personally, I'm scarfing up as much of the older CI-4+ Rotella "T" 5w-40 stuff as I can (found 4 gallons yesterday at Wally's ) for use in my one older, gas powered, flat tappet vehicle. I also use it in the Gator, 955 and 310, but, as long as we can get diesel-specific oils, like the various ones (in my case, J-D 0W-40 and 15-40), which have no "S" rating at all, we're covered diesel-wise. With the number of older, off-road only diesels out there, I'd imagine (hope?) we should be okay for quite a while, in that respect.

 

[Z-Michigan]

Many modern gas engines use viscosity's as low as 5W20. Using a 15W40 viscosity oil is going to effect your fuel economy.

My understanding was that if your engine was designed for say, 5W-30, and you use 15W-40, then after a moderate period of use (I don't know how long) the thicker oil will have allowed more wear, creating bigger clearances between parts, so that while your engine may run fine for a very long time if you stick with that heavier oil, you would never be able to go back without high oil consumption and possibly other problems. Is that true?

 

[Farmwithjunk]

I've heard from what I consider a reliable source that C rated oils aren't good for use with gas engines equipped with catalytic converters. Anyone want to address that?

 

[AlanB]

I've heard from what I consider a reliable source that C rated oils aren't good for use with gas engines equipped with catalytic converters. Anyone want to address that?

Are you / they saying C only, or CS rated oils?

My thought would be that if it was rated for gas engines, such as the Rotella 5W-40 mentioned, there would not be an issue.

But one thing I love about these boards is I am always learning something.

 

[Wayne County Hose]

We use Castrol RX Super 15W40 in everything we own (even the hydraulics)but dont have the cold weather you guys get . As stated earlier Diesel oil has more detergent in it to cope with the soot , it will cause no harm in a petrol engine . But do not use it in a Propane engine . Propane has an acidic by product that attacks the white metal on engine bearings . You must also not use normal petrol engine oil in a Propane engine for the same reason . I have seen bearings stripped of all white metal within 25,000 miles . You must use an oil such as Penrite HPR Gas to prevent bearing failure .

?????? I've been a forklift mechanic all my life. We used regular gasoline rated oil in them forever and never had a problem. I can show you propane forklifts 40 years old that have run regular oil in them all their lives.

As far as running one oil in all your equipment, do you run one fuel in them all? One anti-freeze? One tranny fluid? Then why try one oil?

 

[Egon]

Propane and natural gas engines can run on oil that has less detergent qualities as the combustion process produces less. They also run much cleaner than the other engines.