Oil for Generac 5500XL

[WishIhadatruck]

I have a Generac 5500XL with a Generac 11HP motor on it. I bought the generator back in 1998 or 99 and have mostly used 10W-30 in it. The owners manual recommends 10W-30 in the summer and 5W-30 or 5W-20 in the winter. I rarely use it so I don't want to switch between summer and winter, I want to use the same oil year round. I'm thinking of switching my John Deer LX277 with the twin cylinder Kawasaki engine over to Rotella T Synthetic 5W-40 which should work year round for it and wanted to use it in my generator also but I got the manual out and after the above recommendations is says DON'T use 10W-40. So I'm thinking I shouldn't be using any 40Wt?

The only old relevant thread I found was this one and the opinions there were to ignore manufactures warnings not to use 40wt oil. Any new opinions? Any other oils I could consider for my two small engines? I'm thinking of using GC in at least one of my cars and have that available also. I have too many kinds of oil on the shelf and want to get down to 2 or 3 if possible.

Thanks

 

[androbot2084]

John Deere sells a 0w40 synthetic oil.

 

[Rickey]

I believe that Generac makes their own engines? So my Briggs and Stratton experience may not apply all that well here. FWIW I am running Castrol 5w50 in my 5500w Briggs powered unit with good results year round. The manufacturers advice against 10w40 could be due to that grades historic reliance on large amounts of viscosity index improvers. The possible reasong here is that the large dose of viscosity improvers would break down in a hotter running air cooled engine causing sludge and"problems" Another possible reason for their objection to 10w40 is that it may be simply too thick for their engine. IMHO any modern HDEO should be OK for your application, but what do I know?

I didn't make the engine. Good luck. Rickey

 

[WishIhadatruck]

Yes, this particular Generac model has a Generac engine. I was hanging up something in my garage last night and had to move the generator out also so I decided to go ahead and change the oil. I ended up using GC. I also use WIX filters on all my equipment and cars. I did find something interesting when putting my generator manual back in its file. I was looking through the 3 receipts from the equipment dealer I bought it from and one of them was for a engine speed adjustment when under warranty and they had charged me for an oil change. They listed Rotella 15W-40 on the receipt as the oil used. I guess they don't pay any attention to the factory recommendations either?

I think I'm going to try and consolidate as much as I can on GC if it seems to work well. Cost on the small engines is small since they only get yearly changes anyway so the fact it is more expensive won't mean much.

Thanks for your imput.

[ August 20, 2006, 09:29 AM: Message edited by: WishIhadatruck ]

 

[Best F100]

I also have a Generac generator (15kw, air cooled, home standby, natural gas fueled). I have GC 0W30 (green) in it now. I would recommend that you use it over the Rotella 5W40. My reasons:

1) GC 0W30 will pump better in winter temperatures (I am in the same state as you, similar weather).
2) Shearing is a non issue with GC in summer.
3) You will probably give up a fraction of engine horsepower moving up to a thicker 40 wt. Do you have any extra HP to spare?
4) I would think that you could run full synthetic GC for a longer interval than group III Rotella, if needed.

My generator ran for 50 hours non stop in 90F temperatures during power outages. Also ran for 30 hours non stop during a 10F January ice storm. Personally, I like the thicker 0W30's year round best in my Generac like GC or Esso XD3-0W30 (cross over the border to get it). I also have tried straight 30wt Havoline and Mobil 1 10W 30 over the years.

Also, I was certain that Briggs & Stratton makes all the Generac air cooled generators. Any of you experts correct me if I am wrong about anything I have said here.