Better understanding oil

[NeoGenesisMax]

Ok I have been reading up on oil in regards to the 300gti. I havent found the suggested 5w-50 it suggests just yet but I'm not done.

My dealer told me to always use a motorcycle oil a while back. It would seem that the only difference is that there is a JASO rating for wet clutches. Well the GTI has a dry clutch so that rating isnt needed. The service manual and owners manual only list an API rating and that it should be for four stroke and synthetic. So does this mean I can use a good quality car motor oil in it?  Motul Scooter power is what i used ij the past but its 15 a quart and i think it isnt any different than a normal oil except the word scooter on the bottle. I could buy royal purple for less than that.

[BettinANDlosing]

People have personal preferences on this topic, and these engines aren't complex like cars (low oil pressure) so there's a little more wiggle room. Recommended oil from Kymco is diesel oil, 15w40. The diesel oils are designed to absorb more carbon before breaking down, single cylinder engines and small engine in general have more blowby causing the small amount of oil to break down quickly. That being said I use Motul 7100 synthetic, like I said personal preference. If you use non synthetic I wouldn't personally let it go more than 1000mi per change, synthetic is good past 2000 if you check the level. 5w50 will be good for summer riding but if you ride in the cold, best to use 10w40 or even 10w30.

[de dee]

my manual says 5W 50   that is good for high temp, and low temp,  next oil change ill try rotella T6 5 W 40 full syn.

[nushipwright]

the question may be stupid but here it comes:
is it a bad idea to mix various oils? for example: I've got almost a liter of 10w40 semi synthetic left from previous oil change. am I safe mixing this with other brand 10w40 if I can't buy more of the same? or should I use only same manufacturer brand type?

[mrmike]

       I don't believe there is any problem with mixing oils. I've used two different brands at times when working on my vehicles. In my GTI300, I run a 10w-40 full synthetic in the engine and a 75w-90 full synthetic in the rear diff. I use a good quality automotive oil with no problem. It's cheap and easy to do, so I change my oils out at 1000 mile intervals. Everyone will have different opinions on this, but I prefer full synthetic oils and change them frequently.

[nushipwright]

thank you for your answer! if changing oil every 1000 miles, how often do you change the oil filter? how does the oil coming out look like after 1000 miles? should be pretty clean I guess...

bit back on mixing oils subject. maybe i'm pushing it but is it wrong to mix 10w40 with 5w30 for example? I don't intend to do that but would like to learn more about this.
also why some people say it's better to use diesel engine oils in our scooters? what's the point?

[NeoGenesisMax]

I work at a lube shop and everyone makes fun of rotella. Do yourself a favor anf buy better than rotella. Nowhere in my repair manual or owners manual does it suggest deisel oil. And no it doesnt call for 15w-40 it calls for 5w-50.  If you think 5w if for summet than you dont know what youre talking about. There is no reason to change from 5w especially where I live. 30 may or may not be fine in winter but there is no reason to switch from.5w-50 or 5w-40 at different seasons those two oils are great all year long just check the charts. I was mostly conserned about car vs motorcycle oil in my GTI. Looking at using Castrol Edge full syn 5w-50. It's API rating is higher than required so alls good there. I just dont want to pay $15 a quart for over kill or the illusion of something better. There are many high quality syn oil that are cheaper than that.

[mrmike]

  I bought a dozen oil filters and change them with every oil change. The filter and a quart of oil probably cost me less than $10.00. I also clean the screen every time. It probably takes me twenty minutes to do my service. I come from a military background and believe in PM (preventative maintenance). It's probably overkill, but that's my choice.

  I'm not an oil expert but I do not believe mixing oil weights  will hurt anything. I would use the recommended weight for your climate. I believe you could also mix oil, synthetic blend, and full synthetic if it was necessary. I personally use full synthetic in everything from my vehicles to my lawn mowers, so for me it's not a issue. I have not heard of "diesel engine oil" before, so I can't say anything about that.

[NeoGenesisMax]

Mixing brands of oil or mixing syn vs conventional will not matter as long as the API is the same and the viscosity is the same.  Evidence that mixing syn and conventional is fine is sitting on the store shelves right now.  I'm just not sure when it comes to automotive vs atv vs motorcycle.  It would seem to me that for my purposes automotive oil will be fine since the owner's manual doesn't say anything about specifically getting motorcycle style oil. I was really curious if Zombie would have anything helpful to say on this. And then finish off with some drunken Irish nonsense that we love so much.

[BettinANDlosing]

Don't diss on rotella, anyone who talks sh** about rotella is talking nonsense, jiffy lube rhetoric I assume. It's one of the best all around conventional oils you can get for cheap. Also the only added benefit of motorcycle oil is additives for a wet clutch. Your dealer just wanted to sell you $16 oil. Also my suggestion for weight of oil comes from experience, I prefer using the correct oil for the season rather than a spread out viscosity for "all season".

[alphaBETAdog]

...I also clean the screen every time...

mrmike,

Do you ever get much grime or shavings in the screen?  I got just a tiny bit if fine shavings at the first oil change, but nothing since.

[NeoGenesisMax]

Do you have any concrete facts to support Rotella?  I would love to see scientific support.  Any lab's showing how Rotella stacks up?  The cheapest has never been the best in my experience.  Especially for something you care about. I've read a few studies that showed Mobil One syn and Royal Purple to be very close.  I also saw that Mobile one was close to Castrol full syn.  Mobil one being better in each.  I have also seen that an oil with a 50 rating resist viscosity loss better than several 40s.  Here in KS we get wild temp shifts from high fifties in the morning to hundred in the late afternoon.  Changing oil's with the season is a left over from decades past. I haven't heard one certified master mechanic or any of my auto class text books that say you need to switch oils with the seasons anymore.  Maybe in the 60s or 70s.  If you have credible material stating otherwise I would like to read it.

[TLRam1]

I work at a lube shop and everyone makes fun of rotella. Do yourself a favor anf buy better than rotella.

So all of you guys are equally educated and oil experts, huh? And you all choose to be wrong?

Won't get into one oil brand is better than another, read enough oil analysis and comparisons about conventional vs diesel vs Syn blends vs full syn and extended oil changes. 

Buying quality name brand oil, diesel oil is a heavier duty cycle oil than conventional and will last longer, be it (these seem to be the most popular) Shell Rotella, Mobile Delvac, Chevron Delo 400, etcetera.

[TLRam1]

Do you have any concrete facts to support Rotella?  I would love to see scientific support.  Any lab's showing how Rotella stacks up? 

Yes there are many which I won't waste my time looking for as I already satisfied myself through out the years looking over testing between conventional and diesel oils.

Not between conventional vs diesel but here is one such test, you can't open the analysis but reading the forum you get the jest.

http://www.duramaxforum.com/forum/maintenance/81265-rotella-triple-protection-oil-analysis.html


Can you prove Rotella is not any good? I don't believe you have any analysis showing such compared to conventional oil.

Today's Brand Name oil is good stuff and there is a lot to choose from, buy what you like, in vehicles with oil filters you can do extended oil changes with better oils if you choose. If you need proof, send your oil in for an analysis and get involved over at Bob is the Oil Guy forum.   

[BettinANDlosing]

^^^^^^ couldn't have said it better myself