5W40 synthetic diesel engine oil in a modern gasoline engine?

[sixdogs]

OK, so in my new Toyota that calls for 0W20 I had planned to run that in the winter and 5W20 in the summer. It stays pretty warm here and I park in a warm garage. Any problems with this? I got lost in the conversation.

 

[Soundguy]

I have a tone of antiques that want everything from straight weights and different multigrades.

I run 15w40 c/s rated oil in all my tractors now except for 2 I did some engine work on, switched those to 10w30 syn.

My diesel trucks run 5w40syn. My gas HD van is ?5w30 syn or blend, but its handled by the dealer, I don't do any work on it as its in warranty and has a service plan.

 

[arrow]

OK, so in my new Toyota that calls for 0W20 I had planned to run that in the winter and 5W20 in the summer. It stays pretty warm here and I park in a warm garage. Any problems with this? I got lost in the conversation.

I could give you a lame answer such as "it shouldn't be". In your manual it should state the allowable parameters for oil usage and I would go by that more than I can lend to the subject. There could be manufacturers oiling rationale the common man is not aware of beyond easier cold temp start up. Does Toyota presently also recommend a synthetic?

On a side note, back in the early 60's when "funny cars" were being born, we often used straight 50 weight for runs. Although synthetics might have had existence then, if it didn't say "Valvoline" on the can it wasn't in the shop. Now they use mostly 70 wt synthetics and not just for the reason of lubrication.

 

[Soundguy]

Might have been in existence? 60's?

Try 1913 for the patent. Germany was using syn oil products in ww2.

Bergius , coal-> fuel direct.

 

[RalphVa]

OK, so in my new Toyota that calls for 0W20 I had planned to run that in the winter and 5W20 in the summer. It stays pretty warm here and I park in a warm garage. Any problems with this? I got lost in the conversation.

Why change to 5w20 in the summer? It's 20w at operating temperature. At startup, whether 0w or 5w, it's way heavier than at operating temperature.

Ralph

 

[RalphVa]

If I could get 0w30 synthetic diesel rated, I'd use it in everything. As the market goes, I'm using 5w40 Mobil 1 or T6 5w40 diesel rated in everything except my Tacoma and Jetta TDI. I put 0w20 in the Tacoma to get more mpg. In the TDI, I put 5w30 Castrol special ESP stuff from the dealer because Mobil 1 ESP is not available locally and is much more expensive.

One of the reasons I like the 0wxx is from my experience with my VW Cabrio. Its hydraulic valve lifters (I'm assuming they were; only thing that makes sense) apparently drained down a bit after shutdown. Therefore, they tended to "pound" at startup. I noticed they pounded less with 5w30 oil that I had it on initially. When I found 0w30 and put it on it, the pounding virtually quit.

Ever hear really bad hydraulic lifter pounding? My dad ran a service station. Our HS principal came in and had his oil changed. He quickly came back after taking it out, and the engine's hydraulic lifters were pounding (knocking) like mad. Turned out Dad had forgotten to drain out the old oil. The crankshaft was churning up the oil surface and producing a huge amount of foam. Guess the oil pump was pumping a lot of foam and therefore filled the hydraulic lifters with air instead of oil.

You get the pounding if the lifters have air in them instead of oil.

The other reason I like as how a "cold start" oil weight possible is from an experiment that Imperial Oil did. They put a Chrysler or Dodge 4 cylinder 1980s car in a -40 F/C room overnight. They'd installed a transparent valve cover. They filmed the startup. Any oil that was heavier than 0wxx produced significant amounts of valve smoking on startup.

I want my valves and upper end lubricated instantly on startup. For me, it's 0wxx if I can get it. If not, 5wxx.


Ralph

 

[DEWFPO]

Why change to 5w20 in the summer? It's 20w at operating temperature. At startup, whether 0w or 5w, it's way heavier than at operating temperature.

Ralph

I agree. Your new Toyota can go for 10K on the oil using synthetic. Just stick with the 0W20 year round. No need to change for seasons.

DEWFPO

 

[sixdogs]

The Toyota Tacoma 4 cylinder pickup comes with 0W20 synthetic from the factory and a 5,000 mile oil change interval. Maybe it has to do with the additives required for the "0" rating and mentioned earlier in the thread? Owner's manual says 5W20 is OK but only on a temporary basis and to switch back to 0W20 ASAP.

I would agree that I could go longer on an oil change.

 

[clemsonfor]

I keep 5w-30 oil for the cars and truck..
and Rotella T6 synthetic 5w-40 goes in the tractor, zero turn, ATV, motorcycle, push mowers, generator, water pumps, Etc.

This is what i would do and i do do.

Only time i would differ is in the newer fords and stuff like last 8 years or so that take 5w20, not sure if GM has gone to this weight yet?

 

[clemsonfor]

I used to be in the same boat with lots of different oils on the shelf. Now I use Rotella T5 10W-40 in everything from lawnmowers, cars, truck, motorcycles and tractors. I haven't had any issues with the wet clutch on my Goldwing Honda while using the T6.

Rotella deisel is JASO certified which is what wet clutches need. I use Rotella in my honda ATV for this reason