Synthetic oil consensus

[Jgreemo]

Hi all, I am curious about the boards view on synthetic oils. Cost vs. extra mileage vs. engine longevity vs. fewer changes etc. The whole shebang. For the people who use synthetics, are you running out to 5 to 6000 miles? How's the gas mileage? How much are oil changes, if you aren't doing them yourself?

I'm looking for some insight into the pro's and con's, so all opinions are welcome.

Thanks,
jon

[CleviteKid]

Hi Jon,

You are not going to get a consensus on this question, just a bunch of individual opinions. You will have to decide if there are enuf similar ones to form a consensus.

My opinion: Soot generation is the limiting factor in how long you keep the oil in the crankcase, and synthetic is no help here. However, if you experience severely cold winters (in San Diego ? ?) and need help in starting, synthetic is recommended. If you tow heavy loads up long grades in very hot weather, the better thermal resistance of synthetic engine oil can help your engine and your Banks turbo survive.

Any other operating profile will be handled quite well with Shell Rotella T, or Chevron Delo 400 or Mobil Delvac 1300, changed every 3000 to 3500 miles if the truck will be sold before 100,000 miles on the engine, or every 2000 to 2500 miles if you are gonna keep 'er "Forever".

Dr. Lee http://www.handykult.de/plaudersmilies.de/xmas/wmann4.gif

[G. Gearloose]

Looking for consensus on oil is like asking "Ginger or MaryAnn?".

[CleviteKid]

"Ginger or MaryAnn?" Are "Either one" and "Both at the same time" valid answers ? ? ? ? ?

The Clevite Kid http://www.handykult.de/plaudersmilies.de/devil/diablotin.gif

[NH2112]

MaryAnn. Definitely MaryAnn, by a LONG shot.

Personally, I don't think most people will see enough benefits from synthetic oil to justify the much higher cost. Rotella T and other dino juices got my first 6.2L to almost 300K before I pulled the engine apart (had cracks and leaked a lot of oil but still ran great), and my current one has around 250K on it and still runs great. It doesn't seem to me that synthetic could improve much on that.

I do love synthetic gear oil, though, because even 75W90 gets pretty thick up here in the winter. When I switched to Mobil 1 in the tranny and diffs there was a huge difference in how smooth my cold shifts were.

[Peter J. Bierman]

On the new ( again ) Volvo diesel engines we now recommend synthetic oil and interval off 500 hours
In combination with so called long life filters.
This used to be 250 hours.
Engines with less then 4000 hours can switch over to this 500 H interval.
The secret is the cappacity off the oil the keep the particals floating and transport them to the filters.
Older engines allready have so much sludge buildup in side that the oil is poluted as soon as it gets in couse it starts cleaning the engine.
I've seen engines start leaking since they changed over to synthetic oil, so I guess its true that the oil is cleaning the engine.
The same story goes on modern coolant.

Peter

[ropinfool]

I'm in agreement with Doc!!! :D ;)

[G. Gearloose]

Are "Either one" and "Both at the same time" valid answers ? ? ? ? ? Digitally yes, gramatically no.
Since we're in a 'Digital world'; perhaps.

Remember MaryAnn can also cook up a storm!

[grape]

mary ann still looks good to this day........amazing. Anybody know how old she is?

[ueckebes]

hello ,jon here is an opinion with a little experiance to back it.in 1988 i bought a cheap push lawnmower from walmart, used syn oil in it from day one,change oil once a year in spring ,this mower maintains 3 yards usually so it gets a lot of use. the entire mower is junk but it still runs great i normaly get about 4 years to a mower. the next experiance is with a 82 gm blazer 6.2 diesel high mileage dont drive maybe 8000 miles a year any more ,when it sets overnite it has a lifter tap when first cranked syn oil stopped this and when temps get in low 20,s it also starts easier,and gains oil pressure faster. the next truck is a 82 gmc 3/4 ton with a 6.2 and banks turbo ,still drive this one a lot and use it to pull a lot ,in summer temps when loaded the oil press would drop some esp at idle like at traffic stops syn cured this also ,and in winter it also starts easier.as for as extended oil changes i went from 3500 to 5000 miles, a local oil jobber said this is a common practice but do not get to excessive between changes. also expect a leak to leak a little more. just fyi i also buy my oil at walmart because of conv an price,shell 5w40 12.86 per gallon.i would like to find chevron syn since every thing i own usually runs on conv chev oil. any way if youre worried about high engine temps ,cold starts or long engine life,syn oil is good insurance.how ever i have seen many ford ,gm and dodge diesel engines with 300000+ miles that had very little bearing wear using con oil.hope this shines some light.

[Larry Andrews]

I agree with the thought that good oil in an old motor isn't likely to improve much. I've found that synthetics will help a tight motor stay that way and will also help any motor run a bit quieter. Other than that, it's money down the drain. Engines that leak or burn oil just do it more expensively on synthetics. Also, synthetics tend to have better solvent and detergent properties and seem to knock loose sludge better than petroleum oils do. Not necessarily a good thing.

Having said that, there's NOTHING but synthetics in my race motors...the difference is easy to see there.