Semi-synthetic: What's the point?

[Spyder7]

I would buy and blend my own before I bought a pre-blend. The price for the blend just seems too high to me, when I can achieve a close enough result (IMHO) for a much lower price. Or simply go with one or the other (dino or syn) and call it a day.

I have yet to buy oils with the idea of blending in mind (tempted, yet still not enough to do it) as I ask myself the same question: where is the benefit? If any benefit can ever be demonstrated in doing it, then that might give me the needed incentive to experiment - but if its been posted anywhere, I confess I've missed it.

-Spyder

 

[saberz]

The numbers are to let people know that yes, they can reach that length in miles. Any company will try to cover themselves, they also recommend following the manufacturers recommended OCI. Just like the dumb Engine Warranties from Sopus/Valvoline/Mobil.

Forgot to add Mobil, edited!

 

[kballowe]

It's like this..... if I'm looking at two identically priced oils and one is a semi-synthetic or synthetic blend then that's the one I will buy. Of course, that decision is also tempered by the information that I find on this forum.

Last year I happened onto some Trop-Artic synthetic blend in quart bottles for $1.43 a quart - tax included. Yeah, I got eight cases.

So, right now.... I am a fan of synthetic-blended motor oil.

 

[jstutz]

Originally Posted By: Bill in Utah
Also folks from the Pennzoil Q&A here is the answer on how much syn is in their "blend";

Pennzoil Gold™ is our synthetic blend that contains large amounts of synthetic base stock in all of its formulations, in fact we call out a minimum of 40% synthetic base stock in our SAE 10w30 and 50% in our SAE 5W-20 and 5w30 formulations.

So that is from the "horse's mouth"...

Bill


thanks for posting this, somehow i guess i overlooked this. Also as far as the M5000, from the comparison website, it does have the highest initial TBN and a good add pack. I know its not the final story, but it does look like one of the better ones on paper. I wonder if this is why they quoted the 5k numbers vs the pushed 3k. I still dont understand the syn blend anyway. If you take iron balls and mix them with lead balls then start heating them, the lead is still going to melt at ~600F while the iron will sit there completely unharmed to over 2000F. I know there not related but it gets my point across. I guess if it is a blend, you have less of the lower quality that oxidizes so you will have less deposits, varnish ect. I guess you would under normal conditions get better cold flow and overall less oxidation just because there is less of the lower quality stuff in there.

 

[uart]

I'm using a synthetic blend at the moment. In the past I've just used dino, but here in Australia so much of what's on offer is 15W40 or 20W50. For my newer car I wanted to use 5W30 and I just couldn't find anything dino of that weight on the shelves of my local autoparts store. So in my case I had to go to synthetic blend just to get the required weight oil.

 

[mechtech2]

Semi synths must be some sort of an upgrade from dino.
Why?
Because all 5-20s are at least part synth to pass their tough specs.
For anything else, options are nice.

 

[lexus114]

Originally Posted By: sangyup81
Originally Posted By: Bill in Utah
Originally Posted By: sangyup81

Mobil Clean 5000 is conventional. Mobil Clean 7500 is semi-synthetic. Seems that XOM believes you can go 50% longer on a blend


And XOM believes you can go a lot further than 5000 miles with Mobil Clean 5000.

More marketing that is working it seems....

What makes you think it is working? Most people are still scared to go beyond 3,000. Jiffy Lube marketing > XOM marketing


When I owned my 01 RX 300 I was scared to go over 3k on Synthetic oil. Due to the sludge reputation. Now I have the 330,and I`m still not totally convinced it has no issue`s.

 

[jstutz]

Originally Posted By: mechtech2
Semi synths must be some sort of an upgrade from dino.
Why?
Because all 5-20s are at least part synth to pass their tough specs.
For anything else, options are nice.


I think they are a upgrade, given all else equal you would get better cold flow properties, higher VI, smaller percentage of the lower quality stuff which would mean less deposits and varnish if you were to cook it. So i guess it is exactly what it says it is. Something between a full synthetic and dino. I have had this discussion before about if you mix say full syn and a dino half and half, do you get an all around better oil or do you just get less of the worse oil meaning say one oxidizes at 500F and one at 300F. If you mix them do you get Oil A that oxidizes at 400F or do you get oil B. B would have half that oxidizes at 300F and the other at 500F. Now bring the temp up to say 350F. Well if oil A is in there all is good. If B is in there then you just have 50 percent less oxidation because half of it is not oxidizes. Of course im useing oxidation but you can throw any variable you want in there that is negative with heat. I think the answer was you get oil B.

 

[ChrisD46]

Normally I would go from conventional straight up to synthetic . My dealer just gave me an oil change with Kendall semi - synthetic plus Hyundai filter for $17.99 . My engine sure likes it better than the factory fill . Then there is MC semi - synthetic which has even better numbers than the Kendall . If I could find a reliable supply of MC semi - synthetic 5W 20 for no more than $14.00 5 quart jug it would be my oil of choice . But since MC is hard to find you can do better in the long run looking for deals , rebates of all synthetic oils then stocking up on them .

 

[mikiee]

Originally Posted By: kballowe
It's like this..... if I'm looking at two identically priced oils and one is a semi-synthetic or synthetic blend then that's the one I will buy. Of course, that decision is also tempered by the information that I find on this forum.

Last year I happened onto some Trop-Artic synthetic blend in quart bottles for $1.43 a quart - tax included. Yeah, I got eight cases.

So, right now.... I am a fan of synthetic-blended motor oil.

Sure. If I can get semi-syn for the same or lower than conventional, guess which I'm going with. But other than that, I don't see the logic of not jumping to full syn, if your going to jump at all.

 

[steve20]

I just mix 2 1/2 qt PYB and 2 qt PP in the Honda. No way this engine needs full syn---and this is way better than what is needed anyway. 7.5K OCI



Steve

 

[ARCOgraphite]

I still find it hilarious that most guys here think ISOsyn group iii is equivalent to a good group iv/v blend. What an easy bunch of chumps for the big oil co's

 

[lexus114]

Whoa.....

 

[kballowe]

Originally Posted By: mikiee
Originally Posted By: kballowe
It's like this..... if I'm looking at two identically priced oils and one is a semi-synthetic or synthetic blend then that's the one I will buy. Of course, that decision is also tempered by the information that I find on this forum.

Last year I happened onto some Trop-Artic synthetic blend in quart bottles for $1.43 a quart - tax included. Yeah, I got eight cases.

So, right now.... I am a fan of synthetic-blended motor oil.

Sure. If I can get semi-syn for the same or lower than conventional, guess which I'm going with. But other than that, I don't see the logic of not jumping to full syn, if your going to jump at all.


Yeah, I get it. I know that 5K OCIs with conventional oil are fine for my use. I know that I could double that for a good synthetic. I have no idea what the "semi" or "blend" would do for me so I stay away from them unless they are comparable in price to the other conventional oils.

 

[Bill in Utah]

Originally Posted By: ARCOgraphite
I still find it hilarious that most guys here think ISOsyn group iii is equivalent to a good group iv/v blend. What an easy bunch of chumps for the big oil co's

Yeah lets just IGNORE the PERFORMANCE of most group III oils (and also Group II) and have a closed mind!

Show me a single poor UOA or post on Amsoil XL oil. PP is an excellent performer. Pennzoil conventional also. How about Chevron with their EXCELLENT ISOsyn oils?

Get back to me when you have some FACTS...

Bill

 

[asamek]

Heh.

The motors in my cars aren't going to know the difference between PYB, MC5k, Motorcraft blend, Pennz Ultra, Redline, or any "true synthetic" available - especially for the standard usage they get.

And since I change every 5,000 miles, I don't see any particular need to have the best available $45/qt full synthetic boutique oil in the crankcase.

Might be good for some, but it ain't for me.

 

[BigJohn]

The point of Semi-Syth is......

I just purchased Motorcraft 5w20 in 5 quart jugs for $12 at my local WalMart. Compare that to Synthetics that range from $20.50 to $28.00 at WalMart.

Yep, I will happily spend $12.....for SemiSynthetic.....

 

[Spyder7]

In looking at an impressive UOA on the newly reformulated GF-5 PYB I am thinking hard on doing my own blend. I have two jugs of PP already bought on a $19.88 rollback, while PYB is $11.88 on rollback. Base oils, TBN, and add pack on this new PYB looks really good (love the moly count).

As it already contains a healthy dose of, likely, the same GP III base stock that's in PP (it has to in order for it to attain the TBN and GF-5 spec it has), with add packs that also look similar (more calcium in PP while PYB has the moly PP is lacking in), there is finally some incentive to blend them, and I suspect to good results. The only decision to make is whether to go with a 50/50 blend or 75 PYB/25 PP. I would run this blend in the summer and fall, and likely do a 7k OCI on it which should be easy on the oil but still leave some TBN and healthy additive and wear numbers (I may UOA it just to get an idea of how well it turned out).

-Spyder

 

[sangyup81]

Originally Posted By: ARCOgraphite
I still find it hilarious that most guys here think ISOsyn group iii is equivalent to a good group iv/v blend. What an easy bunch of chumps for the big oil co's

performance/cost, group III is far superior
if you want to beat that, get the M1 flavors that have III and IV blended together

 

[Spyder7]

Originally Posted By: sangyup81
Originally Posted By: ARCOgraphite
I still find it hilarious that most guys here think ISOsyn group iii is equivalent to a good group iv/v blend. What an easy bunch of chumps for the big oil co's

performance/cost, group III is far superior
if you want to beat that, get the M1 flavors that have III and IV blended together


What percentage of each is in M1 and how do you know it isn't mostly GP III?

Just to play devil's advocate, as I disagree with Arco completely on this and see nothing wrong with GP III oils, such as the one I'm using now.

-Spyder