Switching to synthetic blend from conventional oil?

Getting ready to do an oil change and went to Walmart to pick up my Castrol GTX oil and found that it says that in the 5w 30 it is now a synthetic blend. Apparently it is called ultra clean. After doing some research the additive they put in it is synthetic. Which makes it a synthetic blend. My question is, is it OK to run synthetic blend if I have been running conventional oil all this time ?

 

why not a full synthetic ? just curious ?

I buy Walmart Super Tech full syn 5w30 on line in 3 packs...$14 a jug shipped

 

This has been long debated and I had the same question several years ago so I decided to ask a couple dealer service departments and ase mechanics. All of them said it was OK to switch without hesitation. Take that for what you will but I did it ten years ago and never looked back. The particular vehicle I did it on is still running and has no issues. I sold it to a buddy and he is still driving it to this day.

 

As long as it meets the SAE standards required by the vehicles mfg; yes its ok.

 

IMHO, if you are good with sticking with your oil change maintenance interval, the type of oil is not important. I change my oil around 3k miles and go with whatever is on sale. I switch back and forth between conventional, semi, and full synthetic all the time.

 

Thanks guys for all your replys ! I have thought about going to full synthetic many of times. I have even done research on it but being old faction and then having some people tell me different issues they had I keep veering away from it. But I will readdress it once again. Thank you again for personal experiences. Much appreciated !

 

Full syn....run it twice as long.......use a good filter.......call it good !

 

Rum synthetics at 5k to 7k intervals .still dont understand why guys change at 3k.

 

I run mobile1. It’s on sale at Wally World several times a years which makes it affordable to use.

 

currently running synthetic Mobil 1 5w30 from Wal-Mart, usually comes out to $12 per big jug after the promotional rebate that M1 runs often (mail-in or online)

 

No problem running synthetic.

 

This one's been debated many, many times and there is (and never has been) a problem with switching from conventional oil to synthetic or the other way around. Mike drop. Personally, I run full synthetic and a premium filter with 7,000 mile change intervals.

I do remember being in a local Pep Boys store about 5 years ago and a customer asked a clerk the exact same question. Much to my surprise, the clerk launched into a long dissertation about how one should absolutely never switch or even mix the two kinds of oil. I listened in for several minutes in utter amazement, then walked by and said, "I suppose you've never heard of synthetic blend oils have you?", then walked out the door. Words fail me.

 

Just use the correct grade oil and be done with it. And...yes...syn will blend fine...and it doesn't cause leeks like some say.

 

Only thing I would say is if you switch go blend, full synth or go back to full Dino. Word is with some synthetics it could be bad but mostly on high mileage as it won’t swell the seals and could leak. If your under 100k I see no issue but stick with it or switch back after or keep on synth. I switched and only SJ synth now.

 

I see M1 on sale at Walmart all the time. But I don’t see any rebates anywhere. Are they on the jug itself or just a flyer nearby?

 

Check Walmart website. They will list it on there when the rebate is go8ng on.

 

Full synthetic changed every 10K will cost less in the long run and protect the engine better than conventional oil changed every 3K. I see no advantage mixing synthetic and conventional. Choose one.

 

Once again thank you guys for all the input and personal experience. I will have to do some serious thing of going to full synthetic.

 

07 with almost 55k miles with oil changes like clockwork every 6 months at dealership for the first 11 years. Starting in 2018 I put in Mobil1 full synthetic with OEM filter - engine runs smoother at highway cruising speeds. 2019 back to conventional oil (its a family communal truck) - zero issues.

My personal vehicle (01 celica) has had full synthetic since the first oil change - it's worth the few buck IMO. My engine builder guy recommends OEM filters with full synthetic. Oil brand for majority of the folks is not a big deal - but those who push their engines, it sounds like the purple stuff is the way to go. I like using mobil one with a little lucas oil mixed in.



I also 100% agree with Marshall - full syn is cheaper route to go as you can run longer between oil changes along with "better" performing oil. I still change oil every 6 months despite low miles.