My parents had a Briggs PPDX20, 20kw generator installed at their house last year, V-twin 993cc Briggs Vanguard engine. According to the manual it has SJ rated synthetic 5W30 from the factory. My mom wants me to do the maintenance on it, Briggs recommends 15W50 in this engine for continous use commercial duty applications, 20 degrees to 130 degrees. I think the 15W50 would suit it much better, and being natural gas it burns very clean. I see Redline offers a Powersports 15W50, Amsoil offers a 15W50, and was also looking at HPL, not sure if they have a 15W50. It has a 10 year warranty, also considering just sticking to the Vanguard 15W50. I dont mind spending the $$$ for oil for this unit, the oil and filter will be changed every 100 hours or yearly. Which oil would you run? South Louisiana so it doesnt get very cold.
Natural gas generator
- Thread starter mobilnissan1991
- Start date
I mean to keep the warranty I'd just use the Vanguard oil as it's probably more than enough for the job.
JHZR2
Staff member
What Briggs specifications exist? I thought they usually cite API “S” specs. And often SAE30c though not necessarily for gens that need to start in the cold…
I couldn't tell you what's in the manual of this NG Generator but you bring up my point again... If they are siting API S Spec then use it. Make sense? You mention they often bring up SAE 30 but apparently they are referencing 15w-50 in the OP manual. Again... follow the manual & any specifications required.
the manual spec's 5w30 syn.
page 30
IF that is not the right owners manual I saw several others with the same.. and the OP also states the OM = 5w30.
page 30
I would probably run 5w40 in it. my 2 cents.
IF that is not the right owners manual I saw several others with the same.. and the OP also states the OM = 5w30.
I would run a 15w-40 HDEO like Rotella T6. Alternatively Mobil1 makes a 15w-50 that is readily available at Walmart. AFIK there is little if any difference in HTHS viscosity between 40 and 50 weight oils.
It's a Briggs and Stratton v twin so it probably has a flat tappet cam. You probably don't want to run sl or sm oil in it.
It calls for sj so that right there tells you it's probably a flat tappet cam.
Is royal purple still SJ?
Mobil1 4t 10w-40 oil is like sh or sj rated.
Mobil1 v-twin 20-50 is like sg rated has an obscene amount of P, Zn, Ca.
I wouldn't mess with redline, it's double the price of probably any reasonable choice.
It calls for sj so that right there tells you it's probably a flat tappet cam.
Is royal purple still SJ?
Mobil1 4t 10w-40 oil is like sh or sj rated.
Mobil1 v-twin 20-50 is like sg rated has an obscene amount of P, Zn, Ca.
I wouldn't mess with redline, it's double the price of probably any reasonable choice.
JHZR2
Staff member
So that’s a good point. Are the lawnmower oils filled with extra zddp? Don’t SL like still support high zddp and flat tappet cams? I thought that was the last one but it’s not something I retained in memory.
But if ZDDP is really a key attribute, then we need to consider that in some cases.
I wonder if motorcycle oil is the best bet besides the “HD 30” type oils. Even some of those now carry higher api S ratings which would imply lower zddp. I’m not sure motorcycle oils do. Isn’t there another JASO rating for those?
Looks like royal purple is sp rated.
Some motorcycle oils have ag, sh, sj rating.
The sg and sh rated oils have a a bunch of zddp. Around 2x to 3x your typical sl oil.
Look up a VOA for mobil1 v-twin oil there's a few on here. The zinc content is nuts.
Some motorcycle oils have ag, sh, sj rating.
Briggs and Stratton oil at Walmart was sj rated as of last year.
The sg and sh rated oils have a a bunch of zddp. Around 2x to 3x your typical sl oil.
Look up a VOA for mobil1 v-twin oil there's a few on here. The zinc content is nuts.
JHZR2
Staff member
I think the Walmart bike oil was like sl rated.
JHZR2
Staff member
It maybe. I think when I was looking tbe lanwnmower oil and HD30 oils had different ratings, as did the MC oil of course.
It seems like SL may be a good compromise between improvements over older specs for protection and cleaning, yet leaves tbe ZDDP relatively elevated?? I wouldn’t be that concerned with real automotive engines, but these old school air cooled engines, it would seem to be ideal to have a good basestock and lots of zinc.
Good base oil with lots of zinc my lazy answer is mobil1 4t or v-twin.
Do NOT use motorcycle oil in anything other than a motorcycle! They are formulated with MORE FRICTION in mind due to using a shared sump with the transmissions.
Regular Auto Oils & small engine are formulated with LESS Friction in mind due to not sharing a sump with the Transmission. Also, getting the best MPG through less friction.
Well that's the first time I've ever heard of that. What about if the motorcycle oil carries an API license that's appropriate for the automobile? Would it be okay then?
Yeah I'm not worried about it. Been using motor cycle oil in small engines since like 2008 and not about to stop anytime soon.
I used mobil1 vtwin oil as break in oil in my 6.2l diesel when I rebuilt it in 2010 and the last time I drove it was yesterday.
I used mobil1 vtwin oil as break in oil in my 6.2l diesel when I rebuilt it in 2010 and the last time I drove it was yesterday.
This is the first time you've heard that Passenger car motor oils contain friction modifiers vs motorcycle oil?
I seen it first hand. I ran my motorcycle with regular car oil & when I would get into the throttle to pick up speed it would not pick up the pace. I was nieve about car vs motorcycle at first. Then I decided to just buy some motorcycle oil b/c it was on sale & what do you know the transmission was way more responsive. When I turned the throttle now it would engage the trans more & pick up speed with the same throttle input now. Which let me to dig more into the differences. Unfortunately, a lot of folks naysay & doubt as were seeing in this thread.
https://www.castrol.com/en_us/unite...e-oil-and-fluids/motorcycle-vs-motor-oil.html
"Passenger car motor oils also contain friction modifiers which could lead to slipping and acceleration loss in a motorcycle. And modern cars require lower viscosity motor oils that may not protect gears properly in a motorcycle and could lead to gear failure."
https://www.mobil.com/en/lubricants...ts/difference-between-car-and-motorcycle-oils
"In a motorcycle, where the motor oil may lubricate the transmission, a motor oil that does not have the same level of friction modification (for fuel economy) of a typical passenger car motor oil will provide better transmission performance in terms of transmission lock-up and slippage. So motorcycle motor oil does not contain the friction modifiers of a passenger car motor oil."
https://blog.amsoil.com/motorcycle-oil-vs-car-oil/
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Well what I meant was since this is not in a transmission can you still can't use it? What if the motorcycle oil has an API license appropriate for the OP's generator? Will there be too much friction for the generator engine?
