Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
Old 08-03-2016, 08:12 PM   #21
Senior Member
 
Join Date: Jun 2015
Posts: 639
No reason not to use synthetic

Quote:
Originally Posted by nicktano View Post
I went to Cummins to buy oil for my Onan diesel generator 3200, in my MBS 2401R Forrester. I asked for synthetic but was told by the service and parts departments to only use regular oil. So I have only been using regular. I don't know why but the Cummins folks said that they would not recommend using synthetic in their generators. Got me?
I use Amsoil diesel oil for my QD3200 Cummins/Onan with the Hatz engine. Great oil, no issues and I can't understand why the dealer would recommend dinosaur oil - unless that's all they sell.

The only application I have found that synthetic oil is inferior to dinosaur oil is air cooled airplane engines burning leaded fuel.
KatanaPilot is offline   Reply With Quote
Old 08-03-2016, 08:31 PM   #22
Senior Member
 
Join Date: Sep 2015
Posts: 993
Quote:
Originally Posted by KatanaPilot View Post

The only application I have found that synthetic oil is inferior to dinosaur oil is air cooled airplane engines burning leaded fuel.
Is that because of getting certification? Or is it oil additive formulaion? Curious.
Springerdad is offline   Reply With Quote
Old 08-04-2016, 04:23 AM   #23
Senior Member
 
Join Date: Jun 2015
Posts: 639
Exxon tried it

Quote:
Originally Posted by Springerdad View Post
Is that because of getting certification? Or is it oil additive formulaion? Curious.
Quite a few years back, Exxon introduced a full synthetic aviation grade oil. It was pulled from the market after a while, as it was discovered that full synthetic oil did not scavenge the lead (present in the fuel) adequately. So the lead gummed up valves, rings, etc. The lubrication properties were fine.

There are semi-synthetics in use now that work well and with the pending introduction of lead-free aviation fuel, we may see a re-introduction of full synthetics. I personally use Amsoil full synthetic in one of my airplanes that is certified for auto gas, but it's a liquid cooled Rotax engine that prefers a motorcycle-type oil.

Sorry for the thread drift.
KatanaPilot is offline   Reply With Quote
Old 08-04-2016, 07:49 AM   #24
Senior Member
 
Join Date: Oct 2015
Posts: 1,502
Absolutely nothing wrong with using diesel oil in a generator. HDEO oils have a more stout additive package and the engine will thank you for it.

All of my small engines, atvs, motorcycles and all 4 of my turbocharged vehicle engines get 5w40.


Most easily found 15w40s in chain stores are not synthetic.

Amsoil or Royal Purple are available in synthetic in 15w40 but unless you are in the desert 5w40 should serve you well at 150 hour oil change intervals.
Skyliner is offline   Reply With Quote
Old 08-04-2016, 08:15 AM   #25
Senior Member
 
Join Date: Sep 2015
Posts: 993
Quote:
Originally Posted by TonyD View Post
Absolutely nothing wrong with using diesel oil in a generator. HDEO oils have a more stout additive package and the engine will thank you for it.

All of my small engines, atvs, motorcycles and all 4 of my turbocharged vehicle engines get 5w40.


Most easily found 15w40s in chain stores are not synthetic.

Amsoil or Royal Purple are available in synthetic in 15w40 but unless you are in the desert 5w40 should serve you well at 150 hour oil change intervals.
Agreed. We used to service a 'rolling office' motor coach in which the generator ran constantly. We went to Amsoil synthetic 15W40 and a bypass filter, did oil analysis, and were able to stretch oil changes to 500 hour intervals.
Springerdad is offline   Reply With Quote
Old 08-04-2016, 09:07 AM   #26
Senior Member
 
Join Date: Jul 2014
Location: Ayden, NC
Posts: 185
From the operators manual for the HAJAx Series (5500, 6500, 7000 RV QG gensets). The oil used should meets these specifications. The OEM oil is ONANMAX 15W40. The temperature range is for the expected temperatures when you will be operating the generator. If you don't using the generator below freezing temperatures, SAE30 is the way to go. Always check your operators manual. If you don't have the 4 manuals (Operators, Installation, Parts, Service) search the web for the manual document numbers; then search here. Index of /~n0nas/manuals/onan




BBQGUY is offline   Reply With Quote
Old 08-05-2016, 11:48 PM   #27
Member
 
Join Date: Oct 2014
Posts: 32
I attached a picture of the oil recommendation section from my 2015 cummins onan 3200 manual. No mention of synthetic. The cummins facilty rep asked me why I would want to use synthetic, as if I was crazy. He said there was no benefit. Has anyone else spoken with cummins? Interested in what they were told.
Attached Thumbnails
Click image for larger version

Name:	20160805_121827.jpg
Views:	122
Size:	364.2 KB
ID:	116426  
nicktano is offline   Reply With Quote
Old 08-06-2016, 07:55 AM   #28
Senior Member
 
Join Date: Jun 2015
Location: payson, az
Posts: 3,052
I did contact onan about this and here is their reply.


-------------------------------
We have the following response:
-------------------------------

Thank you for contacting Cummins Onan.

Even though your manual says that it is okay to use synthetic oil we do not recommend it. We have found that it gums up the cross hatches in the cylinders. You are okay to use any brand of oil as long as it is 15w40 w/detergent.

If you have any further technical questions please call us at 574-262-4611 and ask for our in house tech.

----------------------------
Sincerely,
Cummins Onan Customer Service



at this point i'm dropping this. I ordered the onan 15w-40 and will use it. I think the key issue is to simply replace the oil per the maintenance schedule. in our case that would be once a year as it's hard to believe we will put 150 hours on the generator in a year. also, exercise it each month. I expect to be just fine.


thanks to all you have offered their experiences and advice.
__________________
2015 cardinal model 3825fl
2015 dodge ram 3500 dually
CHICKDOE is offline   Reply With Quote
Old 08-06-2016, 08:03 AM   #29
Mod free 5er
 
Join Date: Mar 2008
Location: Concord, NC
Posts: 24,705
Mobil 1 is the only purely synthetic oil and is available in 10-40. I use it in all internal combustion engines.
OldCoot is offline   Reply With Quote
Old 08-06-2016, 08:05 AM   #30
Senior Member
 
ilmor's Avatar
 
Join Date: Jul 2011
Posts: 846
Quote:
Originally Posted by NMWildcat View Post
Why? If the oil has the same specifications as the recommended I'd rather not support the manufacturers partner just because.
They don't recommend only their own oil. They provide the specs to use.
__________________
former 2017 Forest River Sunseeker 2250SLE owner - replaced by a Pleasure-Way Tofino

ilmor is offline   Reply With Quote
Old 08-06-2016, 09:10 AM   #31
Senior Member
 
Join Date: Sep 2015
Posts: 993
Quote:
Originally Posted by OldCoot View Post
Mobil 1 is the only purely synthetic oil and is available in 10-40. I use it in all internal combustion engines.
We should add Amsoil to that list. They DO offer semi synthetics as well as full synthetic oils.
Springerdad is offline   Reply With Quote
Old 08-06-2016, 09:32 AM   #32
Mod free 5er
 
Join Date: Mar 2008
Location: Concord, NC
Posts: 24,705
Quote:
Originally Posted by Springerdad View Post
We should add Amsoil to that list. They DO offer semi synthetics as well as full synthetic oils.
Top 10 synthetic oils.
SO, I guess I was wrong saying Mobil 1 was the only one. I do know they were the 1st to come out with it.

Been using it exclusively since 1978.

The Best Synthetic Motor Oil (August 2016) – TopRateTEN
OldCoot is offline   Reply With Quote
Old 08-06-2016, 03:29 PM   #33
Senior Member
 
Join Date: Sep 2015
Posts: 993
Quote:
Originally Posted by OldCoot View Post
Top 10 synthetic oils.
SO, I guess I was wrong saying Mobil 1 was the only one. I do know they were the 1st to come out with it.

Been using it exclusively since 1978.

The Best Synthetic Motor Oil (August 2016) – TopRateTEN
Oh I hate to say this. Actually, Amsoil was first. In fact, their tag line is "The first in synthetics" By a month or so. It was a marketing race. Mobil introduced their 5w30 shortly after Amsoil introduced their 10w40. And oh, did that Mobil 1 leak out of those engines of that era!
I worked in a Mobil station at that time, and my friend was an Amsoil dealer.
Amsoil was originally spelled Amzoil, but there was some trademark infringment, so they changed the spelling.
To that end, they are both great oils, and you can't go wrong using them.
Springerdad is offline   Reply With Quote
Old 08-06-2016, 08:05 PM   #34
Senior Member
 
Join Date: Oct 2015
Posts: 1,502
Quote:
Originally Posted by CHICKDOE View Post
I did contact onan about this and here is their reply.


-------------------------------
We have the following response:
-------------------------------

Thank you for contacting Cummins Onan.

Even though your manual says that it is okay to use synthetic oil we do not recommend it. We have found that it gums up the cross hatches in the cylinders. You are okay to use any brand of oil as long as it is 15w40 w/detergent.

If you have any further technical questions please call us at 574-262-4611 and ask for our in house tech.

----------------------------
Sincerely,
Cummins Onan Customer Service
About the most stupid thing I have ever seen written by a customer service rep. That response is so ignorant!

How does a synthetic oil gum up cross hatches? Does the respondent even know what they are talking about?

Synthetics don't gum up anything and often run cleaner than their conventional counterparts.

If I owned an Onan, I'd use 5w40 oil which is a Group III oil anyway although the bottle says synthetic.
Skyliner is offline   Reply With Quote
Reply

Tags
generator

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 12:19 AM.