I'm sold on synthetic oil, but one ?

[Max Power]

Its been in for less than a week, but the differences are noticeable.

First and foremost, the engine definately spins faster and easier during startup, also its running a hair cooler.

the only thing I can't figger is that after putting 125 hi-way miles on it the oil pressure is creeping up from the usual rock steady 40 psi to around 45 psi, I probably won't get worried until it hits 50psi. This engine has at least 100k on it and I think this is the first synth it has ever had.

I was gonna wait till at least 500 miles, then change the filter only, I will cut it open and see whether the 'detergent' reports about synth oil are true. I'll let you guys know the results.

anyone else ever have a similar experience? Most of the posts I read regarding synth oil talked about a reduction rather than an increase in oil pressure.

TIA,
Robert

ps. I paid 18.88 @ wal-mart for 5 qts of full synthetic 10w-30 q-state. (the mobil 1 was 4 bux more.)

[mark j]

I like Mobil 1- I do go through more oil this way though, the oil is slick and tends to get by rings and seals easier which increases consumption. Probably not as important on these low rpm engines. I'm sure the 3L, 900 HP F1 engines that turn 18,000 rpm sure notice a difference between a synthetic and regular!

[Wagillac]

I have never run synthetic in an old engine so i cant help you with you question but I will recomend that next time you change it you pay the extra for the mobil 1. The Mobil 1 is a try synthetic where as many others have very little synthitic oil in them actualy even thought they say "full synthetic".

http://www.performanceoiltechnology.com/castrolmobilandpao.htm

If you want info try searching google.com , there is tons of info. It can be hard to find good info not just sales pitches but there often are facts that you can go by.
I think Mobil 1 is the best for the price. Amsoil, Royal Purple, Neo Synthetics and maybe others might make even better oil, but I dont think the gains are worth the cost. I would use Mobil 1 and a quality filter. I would change the filter more often then the oil if using a good synthetic posibly. Mobil 1 filters are supost to be the best filter aside from amsoil or somthing like that. Hastings, Wix, and Napa Gold are supost to be decent but diferent tests have had different results and some times names like AC Delco which used to be good change supliers to one of lesser quality.

Well I you can make a little snece out of that. I think I may have went off on a rant semi unrelated to your question :)

[Max Power]

Thanks wagillac, that is some very interesting reading, I spent at least an hour there this mornin. Guess I'll be throwin down the xtra $4 for the mobil 1 next time.

I like the 10 myths page as well... heres the link and 2 of my favorites.

http://www.performanceoiltechnology.com/tenmythsaboutsyntheticlubrication.htm

Myth #2: Synthetics are too thin to stay in the engine.

Untrue. In order for a lubricant to be classified in any SAE grade (10W-30, 10W-40, etc) it has to meet certain guidelines with regard to viscosity ("thickness").

For example, it makes no difference whether it is 10W-40 petroleum or 10W-40 synthetic, at -25 degrees centigrade (-13F) and 100 degrees centigrade (212 degrees F) that oil has to maintain a standardized viscosity or it can't be rated a 10W-40.

Myth #3: Synthetics cause cars to use more oil.

Untrue. Synthetic motor oils are intended to use in mechanically sound engines, that is, engines that don't leak. In such engines oil consumption will actually be reduced. First, because of the lower volatility of synlubes. Second, because of the better sealing characteristics between piston rings and cylinder walls. And finally, because of the superior oxidation stability (i.e. resistance of synthetics against reacting with oxygen at high temperatures.)

[AMX factor]

I had been running Valvoline 10w40 since I bought my GW. Everythign was running fine no leaks etc etc. I decided I'd switch to Val synthetic when I switched our Durango over also. Durango did fine and still is. The GW started leaky everywhere. I tightened everything down and leaks kept coming. At next oil change I went to Valvoline Max Life 10w40 all leaks have stopped and it's back to normal now. Just my experiences with synthetics.

[jeepsr4ever]

I wont use synthetics because i change oil all the time and it gets too expensive

[rfortney]

I have used Mobil 1 for the last 10,000 miles on my jeep it works great. I change oil and filter every 4,000 miles

[Rande]

I recently changed ove to Mobil1 in my '89 MJ Comanche. The valve cover gasket began to leak (imagine that!), replaced it, no more leak.

The engine runs cooler, oil pressure is more stable, mileage went up 2 per gallon. Had it in for 2500 miles now, have only used maybe a pint.

I recommend it for a good conditon engine. You may well experience leaking, but thats generally because the stuff flows better and your gasket was marginal already.

[Lindel]

As far as which synthetic is better, each has their strong points and weak points (good luck finding them, tho). Price is probably going to be the determining factor for most of us. I plan on giving Amsoil a try, just to see.

[Gwamp]

I just switched to synthetic in my 98 Firebird (mobil 1) and I am seriously considering doing it in my Waggie as well since I will have replaced every gasket in the 401 ecept for the head gaskets. Costco has a fair deal on a 6 quart box of Mobil 1

[Max Power]

I think mine is the perfect candidate for this oil, it only gets driven once or twice a week, and used to spin somewhat reluctantly when starting after sitting. Now it absolutely spins faster on startup.
its also got new gaskets for the most part.

I just cant figger why the oil pressure went up, maybe my old oil was diluted somehow. I don't have a mechanical fuel pump and the old oil did not show signs of water or contamination, the filter looked good... of course the old one was a fram and the new is a purolator.... hmmm

[John V]

Amsoil puts out great products as well, and thier bypass filter setup is very effective!

[Mikel]

I just switched to Mobil 1 in my 95 XJ. When I ran mineral oil, I changed it (and filter) every 3000 miles. Mobil 1 I change it (and filter) every 6000 miles. No new leaks...
I pay an extra $20 per change, but if it cuts the oil changes in half, it is very welcome!

[ October 12, 2003, 11:30 AM: Message edited by: Mikel ]