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Changing back from synthetic oil

The independent garage where I have had my vehicles serviced put synthetic oil in both my 2006 Chevrolet Uplander and my 2003 Toyota 4Runner last fall. I specified that I wanted 5W-30 as specified in the owner’s manuals of both vehicles. The excuse was that 5W-30 is only available as a synthetic oil which I know isn’t true.

I’m due for another oil change. I went to another independent shop that I trust. The manager said that there is a possibility that if I switch back to regular oil, the oil consumption may increase and then I would need to go back to synthetic oil. Neither vehicle has ever used any oil between changes. Has anyone ever had a problem switching back to regular oil from synthetic?

There is absolutely no problem switching back and forth.

I use synthetic in the winter months only(easy starts) and conventional in the summer.

Thank you for your response. I knew that the synthetic oil was good in the winter because both our cars sit out during the daytime while we are at work.

Yup…concur…no problem what-so-ever.

Find new mechanics. They don’t know what they’re talking about.

There has not been a problem with switching since the first few years of synthetic oil. Things have changed an it is no longer a problem.

That said does what exactly does the manual specify for oil in that car.  Specs include more than just the weight.  Check both owner's manuals and see what they say.  Many newer cars do specify synthetic, or have specifications that are only meet by synthetic oils.  

Why would not not want synthetic?  It may cost a little more, but it is really better for most uses.  May or may not be worth the additional cost.  My car requires it.

I use synthetic oil in all my cars from my 91 Nissan 240SX to the 03 Tahoe. The winter has nothing to do with using it or not, in my experience its just much better. When ever I have done maintenance on my cars (timing chain on the Nissan, valve cover on the Honda or anything else) the engine is perfectly clean and I attribute it moslty to the synthetic oil. I also double the interval between my changes saving me money in the long run.

Thanks for your input. On my Uplander, a built-in computer tells me to “Change Oil Soon” and that I have less than 5% oil life left. I suppose I could reset the reminder since I’m certain this computer has no idea what kind of oil is in the crankcase.

Neither the Uplander nor the 4Runner requires synthetic oil. I know that the synthetic is a better lubricant and as many years as I drive a car, it may be worth the added cost.

I have a back-up generator with an air cooled Briggs and Stratton engine that requires synthetic oil for year-round use. If the generator is only used in the summer, 30 weight oil is sufficient. If the generator is to be used only in the winter, the specification is 5W-30. Since I never know when we will have a power outage, I use synthetic oil in this engine.

I just don’t want to spoil the engines in my cars. I drank generic beer for years until someone gave me a 6 pack of Heineken. Now, I don’t like the generic stuff. I would hate for my cars to think they need the more expensive oil (don’t take this seriously).

Listen to the OLM. While it doesn’t run out and do a used oil analysis, its algorithms are supposed to take into account starts, stops, restarts, short distance driving and other details to estimate how much oil life is left. If the Uplander is still under any powertrain warranty, I suspect it is important to mind the OLM recommendations.

Change back to conventional if you wish. For the sake of my own info, I would check mileage vs OLM and see which oil is more economical for me, and then start a proper, reasonably economical regimen. I run synthetic only because I extend my oil change interval, but switch among conventional, semi-synthetic, and synthetic based on price point of my purchases.

The Uplander has been out of warranty for more than a year. I have followed the OLM in changing the oil. It predicts longer oil life in the summer than in the winter, which does make sense. I haven’t gone quite 3000 miles on the synthetic oil and the OLM says to “Change Oil Soon”. We’ve had a severe winter and I have made short trips in this cold weather. In the summer with open road driving, the OLM has let me travel as much as 6000 miles before the “Change Oil Soon” message appears.

I did not mean to disregard the vehicles computer, my Tahoe tells me when to change the oil and it will give me more mileage when I use synthetic oil so I listen to its recommendations.

I doubt that synthetic oil is worth it unless you drive your trucks hard or don’t want to change the oil often. It was developed for fleet users so that they could extend the interval between oil changes and save money on staff.

It was developed (in the 1970’s) for use in turbine aircraft engines which needed troublesome heaters in their lube-oil tanks to prevent mineral oil from congealing at high altitudes and extremely low temperatures. Conoco, back then, marketed an automotive product called “Polar Start” which capitalized on synthetics cold temperature ability.