Switching to Synthetic Oil - Flus Needed ???

They'll mix fine, just do as you planned.

Suggest you stick with Mobil 1 10-30 to avoid possible noisy lifters. You should not need to do anything to flush your engine; just change the oil and filter and use a new aluminum crush washer on the drain plug. I have been using Mobil 1 for over 500,000 miles in several cars (latest being a 1995

850 turbo with 127,000 miles now) with no engine related problems of any type. I always change oil and filter every 3 to 5 thousand miles or 6 months, whichever comes first; I know that is probably overkill, but oil is cheap compared to engine repairs.

Just my 2 cents worth.

I got the word years ago from a friend in lubricant research for Standard Oil in the San Francisco Bay Area: the *first* thing with a new product is to make sure that it is absolutely compatible with existing oils from other manufacturers. Unless there were "surgeon general's" warnings as to mixing problems, the liability issues would be huge.

In my "boy racer" days of many years ago, I once used a product that had mixing issues with petroleum based products (it way totally artificial). They warned you and even provided a special flushing material. Both the flush and the lubricant worked just great.

bob noble Reno, NV, USA

I don't think I would worry about it. After all what are syn/reg blends?

No need to flush... just drain it real well. Replace your oil & filter. Just switched to Mobil 1 10W-30 on my "new" 01 V70 2.4T. I just bought it with 62K and replaced oil immediately even though it was at the Volvo dealer at 60K according to it's maint. book.

The cost wasn't even that much different... got it for $4.22/quart. Funny the 5 quart container actually cost about $5.50/quart, so they're encouraging you to buy 1 quart containers.