Can I Alternate Between Types Of Engine Oil

Will I do any damage to my engine if I switch to either a full or semi-synthetic oil at one oil change and then go back to a conventional oil.All of this of course based on using the recommended weight and viscosity per the manufacturer. I ask because it is nice to be able to take advantage of any rebates offered when my scheduled oil changes are due.
Thanks

No,you can’t damage the engine that way! But why do you want to go back to conventional oil? Was the synthetic oil on special that day? The only exception to the rule is that if an engine requires only synthetic oil,it needs to stay with synthetic only.

I am currently due for a change in my '04 Sienna which has 102k on it.I have always used either Pennzoil or Quaker State conventional.Right now there is a special on Pennzoil synthetic blend or full synthetic with a Bosch filter that will cheaper than the conventional oil.Also,right now here in Austin the temp hits over 100F so I thought the synthetic might be a plus.

Go for it.

I’d stock up if the price is that good. Oil keeps a LONG time.

Don’t forget to change the filter with one made for synthetic oil

Can’t hurt, but not necessary if normal change interval is used. Hydrocarbons are hydrocarbons.

Yep! Sometimes I use the conventional filters if I’m short on cash.

Toyota uses the same filters for conventional and synthetic and they are under $6 at my dealer. I get 2 for under $11 from a Toyota dealer online and don’t have to drive to the dealer.

Thanks for all the input.Rebate limit of two per person so I will take advantage of both.

For $30 with inspection (which I can watch) plus a hand car wash and vacuum I have my oil and filter service performed at my dealer. Factory oil filters are also $6.

I would gladly pay that if there were a dealership for either of my two vehicles nearby.

Smart. Watch for oil change coupons and use them when you can. I did a little research for a partner site on the percentage of the cost of ownership that oil changes represent. It’s pretty much nothing percentage-wise. One thing that became apparent is that dealerships run specials with oil changes so cheap they are often hard to ignore. A free car wash has become the de facto standard in my area now.

Exactly. The only difference between the filters is longevity. The ones made for synthetic oil is made for longer oil change intervals…PERIOD.