Going from Synthetic back to Dino

[OriginHacker21]

A friend of mine has been using Mobil 1 5w30 (full syn) for about 30,000 miles on his car. He never takes Synthetic past 3,000 miles just because it didn't "feel" right. Now, he switched back to regular oil (Havoline) because it costs a lot less. He has like 35,000 miles on his car.

What are the possible negative effects on his car? Is this a big no no?

 

[302Xplorer]

None.

All options are open @ 35,000, most will agree.

 

[Tosh]

>He never takes Synthetic past 3,000 miles just because it didn't "feel" right.

Your friend's 'no-no' was going only 3k OCI with synth. You need to work on his feelings.

 

[Ray H]

You "need" to congratulate your friend on his good sense at not feeling trapped into wasting money on short OCIs with pricey motor oil. Suggest that he try one of the ConocoPhillips synthetic blends - 3/4 the way "there" at 1/4 the price.

 

[Propflux01]

Also keep in mind that even 'cheap' dino's will easily go 3K intervals...

 

[Alan]

He went from oil to oil.

 

[mike1qaz]

I ran M1 until 100K and then went back to Pennz 5w20 in my 01 Accord with no issues. I'm at 155K+ now.

I was using 6K-7.5K intervals with the M1 and now 3.5-4K with the Pennz.

 

[mikemc]

If he insists on 3K intervals, a cheap dino that meets API SM is all that's needed. Supertech or Superflo would be good options. Should be no problem to the engine to make the switch.