Synthetic oil in Onan

[Budman]

Originally Posted by chunker21

Since temps in south AL easily hit close to 100 in the summer and below 20 in the winter, 15W-40 for me.

Yea same here in Birmingham. I had genset shut down when dino oil but never w syn. Better in heat and for cold starts (in WV). I use genset a lot when very hot and humid here. When traveling to beach and more than wife and I even use while driving. When traveling anywhere, we use genset to keep small dog warm or cool while eating.
It doesn't cost that much more if u shop ahead of time!!! Thx, Dennis.

[chunker21]

Originally Posted by Budman

Yea same here in Birmingham. I had genset shut down when dino oil but never w syn. Better in heat and for cold starts (in WV). I use genset a lot when very hot and humid here. When traveling to beach and more than wife and I even use while driving. When traveling anywhere, we use genset to keep small dog warm or cool while eating.
It doesn't cost that much more if u shop ahead of time!!! Thx, Dennis.

The cost of oil when looking at motorhome expenses is minuscule. Might as well get good stuff rather than scrimping. Penny wise, pound foolish. That said I don't take recommended intervals and cut them in half or third based on the theory that more/sooner is better.

[Chateau_Nomad]

An important consideration, especially with new generators, is suspended metal/dirt particles recirculating across friction points. It's critical to do oil changes BY THE BOOK - Onan has published those guidelines based on their own engineering data.

As far as conventional vs synthetic... keep the above in mind. Synthetic may give you "better" lubrication qualities and temperature protection... but you STILL have those fragments grinding away inside your engine... especially the small ones with no oil filter. Bottom line is don't try to outthink Onan engineers and fall for marketing hype. You CAN'T GO WRONG by following your Onan maintenance schedule.

[EA37TS]

Originally Posted by chunker21

The cost of oil when looking at motorhome expenses is minuscule. Might as well get good stuff rather than scrimping. Penny wise, pound foolish. That said I don't take recommended intervals and cut them in half or third based on the theory that more/sooner is better.

And I don’t extend change intervals because some oil company says their synthetics better than everything else. Change intervals don’t include a disclaimer that is based on oil type.

Onan and Cummins states there is no benefit to using synthetic.

[EA37TS]

Originally Posted by EA37TS

And I don’t extend change intervals because some oil company says their synthetics better than everything else. Change intervals don’t include a disclaimer that is based on oil type.

Onan and Cummins states there is no benefit to using synthetic.

BTW the HEMI in my WK2 will malfunction by using synthetic. In the case synthetic causes harm rather than good. Search the web for more info.

[Chateau_Nomad]

Originally Posted by EA37TS

And I don’t extend change intervals because some oil company says their synthetics better than everything else. Change intervals don’t include a disclaimer that is based on oil type.

Onan and Cummins states there is no benefit to using synthetic.

"Better than..." is marketing hype. No matter what oil type you use, you STILL have a percentage of metal fragments in that oil at the point where Onan specifies it should be changed. If you extend that oil change interval based on synthetic vs conventional oil... you're buying into a false sense of security.

[Muggs]

There are benefits to synthetics in certain applications. I have never used in race motors except to test. I use where manufacturer recommends. My Altima only use syn, the Suburban uses conventional because it uses synthetic fast, less than 1/2 miles to lose a quart. The RV use syn blend.

Change intervals are between time and use. May be a waste of money sometimes but also go off what oil looks like. When brought RV home, had 1900 miles. Changed oil immediately and every 4500 mile/ annual change the oil looked clearer (not scientific) and same every change. Air cooled generators hard on oil. Most get oil pretty thick and sludgey after too many hours. Racecar change interval depends how many runs and how many issues. Loose piston wall clearances cause lots of blowby fouling the oil.

Everybody has different angle so do what you feel comfortable with. Since I really do not have any oil issues, will continue doing same.

Cost between conv and syn is negligible these days compared to start. Also the actual synthetic designation has changed with time.

[dkoldman]

Still waiting on somebody to tell me what is a bad 15w 40 or 30W oil that meets all of the API specifications?

I think my genset only needed like a quart of oil, I will change every year and sometimes twice a year if I just want 30w over one summer.

We are talking about an Cummins Onan Generator. They have tried to tell everyone in the nicest way possible that there is NO reason (benefit) to use a Synthetic. This is akin to why some folks insist on putting a higher Octane gas in their Car when the Mfg has told them there is no need to, but some feel like they are doing their car a favor by spending more money. In some cases, spending more and makes it worse.

Now I do use fully synthetic in my cars, but that is what the books says. It is not that complicated. If you think about it, there is a REASON Cummins Onan is not endorsing Synthetic oils in their generator engines, and it is not because they didn't invest in Synthetic oil companies So versus just saying out right DO NOT USE, they simply say THERE IS NO BENEFIT but that is not clear to all

[Muggs]

Originally Posted by dkoldman

Still waiting on somebody to tell me what is a bad 15w 40 or 30W oil that meets all of the API specifications?

I think my genset only needed like a quart of oil, I will change every year and sometimes twice a year if I just want 30w over one summer.

We are talking about an Cummins Onan Generator. They have tried to tell everyone in the nicest way possible that there is NO reason (benefit) to use a Synthetic. This is akin to why some folks insist on putting a higher Octane gas in their Car when the Mfg has told them there is no need to, but some feel like they are doing their car a favor by spending more money. In some cases, spending more and makes it worse.

Now I do use fully synthetic in my cars, but that is what the books says. It is not that complicated. If you think about it, there is a REASON Cummins Onan is not endorsing Synthetic oils in their generator engines, and it is not because they didn't invest in Synthetic oil companies So versus just saying out right DO NOT USE, they simply say THERE IS NO BENEFIT but that is not clear to all

Good post. Though pulling a trailer with e450 v-10, in hotter weather there is a propensity to rattle (ping/detonation) some. Since there is no knock sensor, leftover pump premium goes into rv tank. Moving from Memphis to Ashboro NC, used mid grade and unit performed flawlessly on 6% grades.

[Pete'sMH]

Originally Posted by dkoldman

Still waiting on somebody to tell me what is a bad 15w 40 or 30W oil that meets all of the API specifications?

I think my genset only needed like a quart of oil, I will change every year and sometimes twice a year if I just want 30w over one summer.

We are talking about an Cummins Onan Generator. They have tried to tell everyone in the nicest way possible that there is NO reason (benefit) to use a Synthetic. This is akin to why some folks insist on putting a higher Octane gas in their Car when the Mfg has told them there is no need to, but some feel like they are doing their car a favor by spending more money. In some cases, spending more and makes it worse.

Now I do use fully synthetic in my cars, but that is what the books says. It is not that complicated. If you think about it, there is a REASON Cummins Onan is not endorsing Synthetic oils in their generator engines, and it is not because they didn't invest in Synthetic oil companies So versus just saying out right DO NOT USE, they simply say THERE IS NO BENEFIT but that is not clear to all

I think you’re seriously over thinking this! Onan HAD to make a recommendation but obviously you can use whatever makes you comfortable.

[chunker21]

Originally Posted by dkoldman

Still waiting on somebody to tell me what is a bad 15w 40 or 30W oil that meets all of the API specifications?

I think my genset only needed like a quart of oil, I will change every year and sometimes twice a year if I just want 30w over one summer.

We are talking about an Cummins Onan Generator. They have tried to tell everyone in the nicest way possible that there is NO reason (benefit) to use a Synthetic. This is akin to why some folks insist on putting a higher Octane gas in their Car when the Mfg has told them there is no need to, but some feel like they are doing their car a favor by spending more money. In some cases, spending more and makes it worse.

Now I do use fully synthetic in my cars, but that is what the books says. It is not that complicated. If you think about it, there is a REASON Cummins Onan is not endorsing Synthetic oils in their generator engines, and it is not because they didn't invest in Synthetic oil companies So versus just saying out right DO NOT USE, they simply say THERE IS NO BENEFIT but that is not clear to all

I think this subject has been beaten to death. Onan/Cummins has specific recommendations for servicing of the generators, both in frequency and equipment. If someone doesn't want to follow those manufacturer recommendations they are free to do so. Me, I figure that they, the manufacturer, know what they are dong and recommending so I follow those guidelines. I don't need to justify why I chose to, or not to, my choice. Every manufacturer also recommends their own branding of lubricants with the caveat of "or approved equivalent". Since we know Ford, Harley Davidson, Onan, etc., doesn't have their own refineries, using any of the properly API rated fluids works well.