Full synthetic oil

[jimmy braden]

Originally Posted by sbleiweiss

I will say this. My Onan 5500 runs much better on Rotella T5 (synthetic blend) than in did on dino oil. that's a fact.

Originally Posted by sbleiweiss

Because when on dino oil it would quit if it got too hot, and occasionally at other times. Since switching to Rotella T5 it starts easier and never just quits.

For gensets that is certainly possible. Even the kubota motors on the 7500s and up can run hot depending on load and ventalation. The 5500s are usually v-twins running on propane and they are in even more cramped quarters.

[dennis45]

Originally Posted by jimmy braden

For gensets that is certainly possible. Even the kubota motors on the 7500s and up can run hot depending on load and ventalation. The 5500s are usually v-twins running on propane and they are in even more cramped quarters.

Load and Ventilation will most certainly affect engine coolant temperature but I don't understand how oil type would make enough change to cause a high jacket water temperature shutdown.
A residue build up on the sensor due to degraded coolant, a faulty sensor, or a wiring fault would cause a high temp issue but Lube oil Type? I don't think so.

[jimmy braden]

Originally Posted by dennis45

Load and Ventilation will most certainly affect engine coolant temperature but I don't understand how oil type would make enough change to cause a high jacket water temperature shutdown.
A residue build up on the sensor due to degraded coolant, a faulty sensor, or a wiring fault would cause a high temp issue but Lube oil Type? I don't think so.

5500s have no,coolant. Aircooled only, totally dependant on what oil can do...

Cummins Onan 4-Cycle OHV V-Twin Engine (.6 Gal/H @ 1/2 Load)

Quietest in its class w/ excellent fuel economy

[dennis45]

Originally Posted by jimmy braden

5500s have no,coolant. Aircooled only, totally dependant on what oil can do...

Cummins Onan 4-Cycle OHV V-Twin Engine (.6 Gal/H @ 1/2 Load)

Quietest in its class w/ excellent fuel economy

Jimmy, no disrespect but, the the key word there is "Air Cooled".
Oil lubricates and carries heat away from the combustion area. The air moving across the cooling fins takes that heat away.
Dino oil or Synthetic, what's the difference? Explain that to me?

[jimmy braden]

Originally Posted by dennis45

Jimmy, no disrespect but, the the key word there is "Air Cooled".

Oil lubricates and carries heat away from the combustion area. The air moving across the cooling fins takes that heat away.
Dino oil or Synthetic, what's the difference? Explain that to me?

Yes. That's correct. And like i said.,some have marginal space .

Synths do dissipate heat better and can operate at higher temps.
Its obviously right at the limit for this application..

This thread has,evolved quite a bit..and thats why we have no one answer..

[dennis45]

I love Lube oil discussions.

In the world of internal combustion engines, RVs are unique in that, for the most part, they operate less time than they sit still. As such they are more prone to accumulation of condensates and acids in the Lube oil.
The Only Way to remove these contaminants is to change oil. The type of oil is not as relavant as the frequency of oil change intervals.
Synthetic or Dino oil, change oil at least annually and your RV will outlast you regardless of the type of oil.
Take the difference between Synthetic and Dino and buy beer or, go to the opera, what ever lights your fire.

[Al Bundy]

Some synthetics don't cost much more than dino oil especially if you're cheap like me and watch for rebates.
I only need to change once a year so it might cost me $10 a year to run synthetic compared to dino.
I believe it's more important to stick with the same oil you've been using or the previous owner and change it at least annually.
I think it does more harm leaving dirty oil in the motor.

I forget who it was but someone here was concerned that his dino oil was going to hit 10,000 miles and if he should change it on the road.
He ended up sending in an oil analysis and they said it was still good

[Kzoocamper]

Originally Posted by dennis45

Jimmy, no disrespect but, the the key word there is "Air Cooled".
Oil lubricates and carries heat away from the combustion area. The air moving across the cooling fins takes that heat away.
Dino oil or Synthetic, what's the difference? Explain that to me?

I have a couple of questions here:

Does synthetic oil reduce friction over standard dino oil?
If so would that not result in less temperature to begin with in an air cooled engine?
I was always told by the VW groupies (father in-law loved Buggies) that it resulted in a 10 to 15 degree difference at a minimum.

[dennis45]

Originally Posted by Kzoocamper

I have a couple of questions here:

Does synthetic oil reduce friction over standard dino oil?
If so would that not result in less temperature to begin with in an air cooled engine?
I was always told by the VW groupies (father in-law loved Buggies) that it resulted in a 10 to 15 degree difference at a minimum.

Did you feel a tug on your leg?

[George Schweikle]

I think it depends upon the specific oil weight of the oil and the accompanying additives. As an example, many refiners have reduced the Zinc content of their oils since Zinc (ZDDP) is said to be detrimental to the newer catalytic convertors. There have been valve train failures of engines with flat tappet lifters with these low Zinc oils since there is high friction between cam lobes & lifters (Tappets). Mobil One 15-50 still has a high Zinc level so I use this in my two Alfa Romeos with flat tappet engines since the Zinc provides additional lubricity. The 454 Chevy engine in my motorhome is a roller lifter design, with lower friction at the cam lobes, so I use Mobil One 10-30 that is a low Zinc oil.

Originally Posted by Kzoocamper

....Does synthetic oil reduce friction over standard dino oil?....

[grindstone01]

I've read that synthetic oil will run cooler in a motor which is a direct result in less friction not heating the oil. That's all I needed to know to become a synthetic oil user!

[Hooligan]

Oil is just not slippery or cooler. Mercedes for their Bluetec newest diesel engines has an approval list of only (as best I can tell) synthetic motor oils that meet their requirement for "Low SAPS" (Sulfated Ash, phosphorus, and sulphur). These low ash oils limit clogging of the diesel particulate filter. Most are 0w30 or 5w30 weight.

[Kzoocamper]

Originally Posted by dennis45

Did you feel a tug on your leg?

And this nonsense means what??

[Kzoocamper]

Originally Posted by George Schweikle

I think it depends upon the specific oil weight of the oil and the accompanying additives. As an example, many refiners have reduced the Zinc content of their oils since Zinc (ZDDP) is said to be detrimental to the newer catalytic convertors. There have been valve train failures of engines with flat tappet lifters with these low Zinc oils since there is high friction between cam lobes & lifters (Tappets). Mobil One 15-50 still has a high Zinc level so I use this in my two Alfa Romeos with flat tappet engines since the Zinc provides additional lubricity. The 454 Chevy engine in my motorhome is a roller lifter design, with lower friction at the cam lobes, so I use Mobil One 10-30 that is a low Zinc oil.

Bear in mind I was referencing dennis45's post about there being no difference on an air cooled motor. It was a generalization with no regard to additives so I am sure he would have only been referring to best case scenarios....