Oil Change

Oil is oil. If the weight is the same what is the problem? Wouldn't that be a synthetic blend? I don't know why anyone would bother but people do crazier things. Lucas oil supporting race teams is proof of that. I prefer to run the same brand oil every time all the time. In a pinch I would not hesitate to mix another brand. We used to do it all the time with farm equipment and never had any problems. Some people go with the cheapest brand they can find on any oil change. To each their own. I don't think mixing some synthetic 15w40 with dino15w40 is going to cause any sort of issue. I don't know why anyone would but I doubt they're going to have a catastrophic failure if they do nor will they lengthen, shorten the useful life either.

 

Synthetic will likely be a lower viscosity. 5W40(?) or something like that and twice the price. For no benefit. A complete synthetic oil change for better startabity in really cold temps. is worth it, but even most Canadians don't bother. I did it a few years ago, it definitely helped the cold crank and the engine got oil pressure a lot quicker. But at -30 Celsius, I'm not shutting it off anyways and in warmer temps 15W40 does the job.

 

The effect depends on the types of synthetic bases that were mixed with mineral bases. Polyalphaolefin and diester synthetic bases can be mixed with mineral oil bases, which is done regularly to create “blend” products. Polyalkylene glycol (PAG) bases should not be mixed with any of the others unless specialized barrier fluids are used to minimize the incompatibility. When PAGs are mixed into other lubricants, you typically will get strong negative reactions (producing sludge and tacky residue) that require extra effort to flush, clean and correct.
Even if the base oils are compatible, there is the prospect that the additives used to create necessary performance properties could conflict, producing lost lubricant effectiveness.


so it can cause major problems, like in a rear end.

 

Synthetic would NOT be a lower viscosity. 0w40, 5w40, 10w40, 15w40 are all the same viscosity... 40 weight with a viscosity index of around 14.5, mineral or synthetic. The only, and only, difference is the winter flow rating. That is the number in front of the "w". Has nothing to do with viscosity. The only way a viscosity would be lower is to go to a lower oil like a 30 weight. Now to be fair, a 5w40 will flow easier, due to it's flow rating, than a 15w40, but the viscosity is still a 40.

I like a synthetic blend I get from Schaeffer Oil. I get it for a very competitive price compared to anything at Wally World, it is delivered to me for free, and they throw in free oil sample kits and used oil analysis for free also. It is a Group II+ and Group IV PAO blend. Some of the best used oil samples I have ever had on any engine.

If you are adding a synthetic to a mineral on your own at an oil change, then there could possibly be conflicts in the additive package that was mentioned. At least stick within the same brand name to reduce any risks. Why not just get a synthetic blend and get the right mix?

 

As Skateboardman says(producing sludge and tacky residue) is right, we had it happen with a mix with hydraulic and synthetic turned to something like a soft rubber cement, was a big job to get the system cleaned up and luck no damage do to low oil flow. Also semi synthetic could be a tea spoon of synthetic in a gallon with a bigger price tag for nothing.

 

Oil is not oil!!! Mixing a organic oil and a synthetic oil is throwing your hard earned money out of the window. It all depends if you are talking a true group 4 or 5 synthetic or just the bull crap group 3 fake synthetics the oil companies trick you into believing is synthetic.

By putting a garbage regular oil in a synthetic oil all you do is contaminate the synthetic and destroy it's additive packs and detergent blends.

90% of marketed synthetic oils are just blended oils anyways. Only the high end ones like amsoil, mobile 1, royal purple, I think Rotella t6 are g4. And red line is the only true g5 I know of.

If you have some kicking around it ain't gonna hurt anything but don't think your doing your engine a favor by adding a half breed oil to it. The oil is only as good as its weakest link.

 

Oh boy, somebody had to start talking about oil again......

 

I worked at a truck dealership and would get the oil left in 5 gallon pails, they would just throw it out, I mixed it in 6 gallon gas jugs and used it in my equipment it worked great, it had every brand of 15/40 and some synthetics, I never had a problem. engines were cleaner than most I worked on.
Last fall I was changing my oil, I use synthetics in my loader and dropped the oil in my truck, then I found out someone had used the other pail of Dyno oil, so I mixed shell dyno and Dello 5/40, it worked great.
Oil is oil, it is the cheapest overhaul you will not need. I add, from a Quart to a gallon of ATF Dex 3 to the oil at least a half hour working time before I change the oil every second change.
Just a thought!, Remember voter seppretion has 2nd amendment fixes

 

I would suggest anyone interested in doing more digging to head to http://www.bobistheoilguy.com/.

He has a complete write up on why Lucas additive is mostly a scam. Yikes!!