Switching from synthetic to regular oil?
 

Can someone answer this question? Is it true that once you switch to synthetic oil, its harmfull to go back to non synthetic? or is that a myth? I've heard that said so many times, but was never really sure of its validity?

Its just getting to hard to find 15/50 mobil 1, all the stores in my area are always out, its been that way for a year now. Plus the cost seems to be too high.

Can anyone recommend a good non synthetic easy to find oil for a high milage (165K) 92 400E?
Thanks

I

Go to a local independent parts dealer and they will order for you in case quantities. Skip the chains for special orders. In most cases my local guy can have the parts/supplies that afternoon if ordered by 10:00am.

Tim

No harm
 

No harm will come from switching back to mineral (dino) oil. As a matter of fact, I often switch back and forth on my Isuzu Rodeo. Due to a sticking hydraulic lash adjuster that makes the valve tick occasionally, I switch to a Mobile 1 0-30W oil for an oil change, which according to the factory is supposed to relieve the problem. The only thing is this: I don't care what the oil manufactor SAYS their oil can do for change intervals, I go by the manufacturer's recommendation for extreme service, which is 3500 miles. Changing with synthetic every time is expensive....

I have been very happy lately using Rotella 5W-40 synth, or Rotella 15W-40 dino oil, available at Walmart in gallon size.

Its a myth.

Usually the stores around here always have 15w-50, its the 0w-40 that seems to be hard to find sometimes which is what I use.

I get my 0W-40 at the dealer, for about the same price as the independent parts dealers( if they had it ). :)

My 86 300E with 233,000 miles developed a lifter tick, could not identify which one as the noise came and went, ran Marvel Myster oil thru the Dino oil with no improvement, changed to REDLINE brand 20/50 synthetic oil and the noise disappeared immediately and has not returned and that was 3 months ago. :)