When synthetics first came out there was some trouble with the seals. As the chemist firgured out the additives, the performance improved. See: http://bestsyntheticoil.com/content222.html - Bill
Walmart has Mobil1 for about $22 for 5qt jug. Hard to beat. Be careful not to get the conventional (from the ground) Mobil oil. It needs to say "fully synthetic" on the label, or similar verbage. When talking about leaky seals, I've heard it is many times caused by age and sludge. To clean out the sludge and recondition seals, I have had good success with an oil additive called AutoRx. Pretty sure you can still get it online. They make a product that slowly dissolves crud in the lubrication system of an engine (or trans or steering system, for that matter). It is not like a kerosene flush at all. I give it credit for cleaning a stuck ring and some noisy hydraulic lifters that had become plugged while in the posession of the first owner of my now daily driver. http://www.auto-rx.com/ (I am in no way affiliated with Auto Rx, just a satisfied customer)
i purchase zddplus from a supplier in ontario and add one bottle to each oil change (castrol gtx 10w40) for my 72 buick gs. it may cost a little more but it is best method.
Thanks everyone for their opinion. Just for the record, I'm a huge fan of synthetic oil. I just remember reading an article about using it in an old engine. Throw in the ZDDP issue and you have some confusion on my part.
Thanks Larry. So what if my oil capacity is 6qts? I ain't putting 8 ounces in just for one more quart of coverage. :error: Safe, proven ZDDP EP agent takes the worry out of using new oil formulas in classic engines. One 4oz. bottle of ZDDPlus will restore 5 quarts of modern SM quality oil to the optimum level which existed when our cars were new. Compatible with ALL high quality oils, standard or synthetic. Reduces cam and lifter wear. Great for use when breaking in a new camshaft.
Ken, I would just put an extra once in for the extra quart. If you buy a 6 pack, that will be enough for almost 5 oil changes.
You have been using mobil 1 for 20 years hints the reason you havent felt any diff... If someone anyone went from conventional oil to synthetic they would feel a diff in the engine. That is a fact point blank. Like larry said it flows better, so if something flows better what is the end result?
Evidently what I failed to articulate is, it's been so long since I switched that I dont recall when the inevitable benefits were noticed. Regarding flow, viscosity is the same out of the bottle for dino or syn: they flow the same. The real benefits from using syn come after sitting in bumper to bumper traffic in August, week in and week out. Dino oil will eventually cook down to a thick goo that wont protect anything. Syn, on the other hand, will stay uniform and true to it's manufactured specs. That's why many users get extended oil change intervals using syn. Run a good filter (or even change midway through an oil change) and get way more miles over dino oil.
here are the links http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/ZDDP_Levels_Classic_Cars.aspx http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_0W-40.aspx
Valvoline Vr1 Racing Oil Has It In It.also Comp Cams Sells Oil Additive That States.put Back Whay Conventional Oils Can No Longer Provide.utilizing A Special Blend Of Extreme Pressure Additives Once Found In Off The Shelf Oils.witch Both I Have Bought From My Local Carquest Store.just My 2 Cents
The Mobil site quotes 1000 ppm zddp for their 0W-40 which may be adequate for a stock flat tappet valvetrain, but with higher valvespring pressures I still think another 50% would be of benefit. I haven't tried 0W-40 yet but considered it with my old oil pump setup to see if I could reduce cold start oil pressure. Don't have that problem with the latest combo, though. Devon
