Synthetic Blend Motor oil....

[biker_bill]

Jeddak Once you use a full synthetic do you have to keep using it?

Great question!
I've thought about that myself in the past.....

 

[ColtAR15]

Great thread. I have a 96 Chevy Z71 Reg cab with 269K original engine 5.7. What oil and filter do you recommend?

 

[Ken Ford]

Oy vey. Lots of misinformation in this thread. I am a BITOG junky.
To OP: Valvoline High mileage is excellent HM oil. It has a higher percentage of syn oil than many other blends. 75%, IIRC. I use HM Synpower and QS Defy (Defy has higher zinc content, same as in SL class . Zinc was really knocked down in SN classification)
Synthetic oil does NOT swell seals. It does, however, clean out crud better than regular dino oil, so it will unmask a plugged up leak. Especially tru about ester based oils (group 5). Esters are natural cleaners.
Engine oils are grouped in 5 groups:
Group 1 basically non-detergent oils. Stay away.
Group 2 dino or conventional oil. Run it for 5K miles.
Group 3 Synthetic (Motul 8100, Valvoline Synpower, reg Penzoil Platinum). Highly refined dino oil, maybe with some hydro cracking. Use for 7.5K miles.
Group 4 Synthetic, PAO oils, such Royal Purple, better Mobil oils. 10K+ miles
Group 5 Synthetic, esther based and all other man-made, G-Oil (made from beef tallow), Amsoil, IIRC, etc.10K+ miles.
Longer oil runs need an oil filter designed to last longer: more robust media, more dirt holding capacity.

Color of the oil is not indicative of its effectivness. Additive package as well as the amount of pollutants dissolved in the oil determine how quickly the color changes. Used Oil Analysis is really the only unbiased way to compare one oil with another in a particular engine.
HM oil does not swell the gaskets either. It has additives that try to restore elasticity to an old seal, but they will not swell up a seal, or fix a physically damaged seal..

PS to comment on color. I added half a bottle of Lubromoly to my minivan's oil this weekend. It had Group 3 Motul8100 in it now. 8100 is a low SAP diesel/gasoline oil. Color changed immediately to darker brown/gray. That's moly in the mix.
I added a shot of Moly to help with with some of the cylinder issues that 3.6 Pentastar has been having. My engine is fine, but I am not an average car owner. I add MMO to the gazoline with every fill-up as UCL and to lube the fuel pump as well as add Moly to boos additives in oil and prolong engine life.

Too paraphrase, synthetic oil is worth the difference. Tear down a pair of race motors used identically and it will become obvious.
I've been using high mileage stuff in my cars if they are over 75,000 since vavoline and Castro started.

 

[Ken Ford]

Great thread. I have a 96 Chevy Z71 Reg cab with 269K original engine 5.7. What oil and filter do you recommend?

I run the HM Synthetic that's on sale.
I use only a quality filter that DOES NOT advertise filtering down to xxx particles.
Back when Deutch was the leader in "filtering down to the smallest particle" I'd say that 90% of the oils starved motor failures had Deutch filters.

 

[DADI03]

I use a HM synthetic blend on my 92 pickup. Mainly because I've heard that once you go full synthetic you can't go back. It only has 165,000 miles on it.

 

[Colossus]

I use a HM synthetic blend on my 92 pickup. Mainly because I've heard that once you go full synthetic you can't go back. It only has 165,000 miles on it.

I dont thinnk you do have to keep on using it.
Like synthetic blend. 50% synth, 50% regular oil.
It's not heroin. )))

 

[Jeddak]

Jeddak Once you use a full synthetic do you have to keep using it?

Great question!
I've thought about that myself in the past.....

Nope, you do not. You might notice a slight oil consumption as you change back and forth, consumption that will stabilize, but that can happen with change in oil brands too. Engines react differently to different oil additives (friction modifiers, acid neutralizers, anti-wear agents, etc)
I ran Valvoline NextGen semi-syn and QS Advanced Durability (dino) and Mobil 5000 (dino) in my minivan for 3 years, alternating back and forth, now it is Motul 8100 synthetic, next time it will be Mobil 5000 dino (need to use it up), then TropArtic semi syn, then M1 AFE syn. No leaks, no issues, still purring along.

 

[Jeddak]

Too paraphrase, synthetic oil is worth the difference. Tear down a pair of race motors used identically and it will become obvious.
I've been using high mileage stuff in my cars if they are over 75,000 since vavoline and Castro started.

Especially in the engines prone to sludge, like some of the Toyota and Saab engines.

 

[Bennyboy]

I'll share a little anecdotal experience of mine: in 2008, I purchased a new Mustang GT which I promptly started modifying. I hammered on that car every day, lived at the dragstrip, and was always looking for something else to eek power from it. I had been running Mobil 1 full synthetic for a while but decided to try out Royal Purple since it was getting a lot of publicity at the time. After swapping, my engine was noticeably louder and more coarse.After a few thousand miles, I swapped back and it was immediately quiet and smooth again. This sold me on Mobil 1 (anecdotal, like I said).

So I started researching and found BITOG and Blackstone Labs. Had the M1 checked in that car and a few others and it's always came back perfect despite constant flogging and nitrous use. I've since started a procedure for every new car I buy (which has been several, a bad habit of mine). At 1,000 miles I swap to M1 FS in the manufacturers recommended weight and change it every 10k with a good filter, usually go with Bosch Extended Life. Never had an issue and the lab results are always great.

 

[Old_School]

You can use 0w-30 oil in ANY place where 5w-30 is recommended. All it does is give you better start up protection. To make 0w manufacturers have to use much more synthetic base oil and better additive packages (more stable viscosity modifiers in particular), so, all things being equal, a 0w30 oil is more robust than 5w30 oil of the same brand and type.

I didn't know this about 0W30 vs 5W30. Good to know. Thanks!