ILSAC GF-7 / API SQ Conventional and Synthetic Blend oils

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Seems like some of the conventional and blend oils on the market will be licensed to meet GF-7 / API SQ performance criteria. Let's say someone has an older car that is seldom driven and sees very short OCIs. Since this latest spec seems to have limits on deposit formation / sludge that are likely way tighter than the oils of 20 years ago, is there any reason to pick a full synthetic vs a blend for OCI < 3000 miles?

For example, let's say something common like Maxlife 5W-30 blend vs Maxlife 5W-30 full synthetic. Both meet the spec... is the only benefit of synthetic the ability to go longer OCIs? Curious to hear opinions on this.
 
I've had similar thoughts. I have a newer car, but it is not turbocharged or GDI. The only thing recommended is SN or higher and 0w-20. I live in a warm climate and only drive 2500-3000 miles per year. I'm thinking of using a SQ/GF-7 5w-20 synthetic blend at the next OCI. I do annual oil changes to satisfy the warranty requirements.
 
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If your car only calls for a API oil then I'd just use any HM oil. MaxLife is good. What's the difference in price though? I feel like most 5qt jugs at WM are $20-$40. Maybe go with M1 HM/Valvoline EP HM and stretch it to one-year intervals.
 
I've used some older stock magnatec blend 5w-30 in my Mustang with no issues. From what I can tell of the service records, it ran on Motorcraft blend under previous ownership.

I wouldn't hesitate to use SQ or SP blends in it, except that I can usually find full synthetic on sale or rebate.
 
If your car only calls for a API oil then I'd just use any HM oil. MaxLife is good. What's the difference in price though? I feel like most 5qt jugs at WM are $20-$40. Maybe go with M1 HM/Valvoline EP HM and stretch it to one-year intervals.
< 3000 miles is a one-year interval! haha That's why I was asking about blends vs synthetic... I change annually, and that is always < 3000 miles on this vehicle.

Seems to me that if a blend meets SP / SQ it should do as well as full synthetic for that kind of OCI. Is my thinking correct, or does full synthetic have benefits I may not be considering (beyond extended OCI)?
 
< 3000 miles is a one-year interval! haha That's why I was asking about blends vs synthetic... I change annually, and that is always < 3000 miles on this vehicle.

Seems to me that if a blend meets SP / SQ it should do as well as full synthetic for that kind of OCI. Is my thinking correct, or does full synthetic have benefits I may not be considering (beyond extended OCI)?
I’ve used blends for mileages based intervals and time based intervals without issue. How well it holds up is going to be engine and condition dependent. 3000 miles can be hard on any oil with the right conditions.

That said the price difference these days is negligible. NAPA blend is currently $18, Valvoline Maxlife blend is $19, and Castrol GTX blend is $20 for 5 qt. Supertech full synthetic is $18 and Quaker State full synthetic is $20 for 5 qt. You could have a store brand or name brand both in semi or full synthetic for around the same price.

I used blends the first few years on my daughter’s car because it never saw more than 2,000 miles a year. Now I’m using full synthetic because it is being driven significantly more than before. Both have served well.
 
It's like it was meant to be...walked into AZ today and they were clearancing out Castrol GTX Ultraclean 5w-20 SP synthetic blend for $3.00/qt. Bought 6 quarts and a filter.
 
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