Mobil 1

[TheGossert]

Winter is fast approaching and I'm thinking about switching to Mobil 1 to help with starts on cold days. I understand that synthetic oils continue to flow, even when the temps. dip well below zero, which is nice, because I've seen 30 below (F) here, in Minnesota, on several occasions.

The problem is that my '91 GW has high mileage and a leaking rear main seal, and everybody tells me my engine leaks will get much worse with synthetic oil and to stay away from it.

Should I use it, anyway?

Larry

[ October 31, 2002, 12:28 PM: Message edited by: TheGossert ]

[Joe H.]

Synthetic oil will tend to leak more, and it may 'flush out' leaks you didn't know you had. Why not replace the rear main?

[Stuka]

90% of the synthetic oil out there is patrolium based. Ever since Castrol won its lawsuit that synthetic is just a sales term. And in no way means the oil is 100% synthetic and not dino oil. So you are basically paying 4 times as much for some that isnt any better.

I use Castrol GTX ONLY in all my engines. Valvoline has a high carbon build up problem. Penzoil/QuakerState (same stuff) breaks down way to fast, and also build up carbon faster.

Castrol GTX also seams to keep all my old engines MUCH quieter then other oils.

[Sundowner]

no offense, but Mobil 1 is the real deal.

a while back, I wanted to put a V8 in my old truck.

bieng the cynical bastitch that I am, I ran Mobil 1 in my 85 S-10 Blazer 4 banger for 3k miles, DRAINED it, and drove 140 miles round trip at an avg. of 75mph (about 3500rpm) and the thing didn't even run warm. that was 4 years ago and Iv'e since sold that truck to a friend. and it STILL runs and doesn't burn oil.
I only use mobil one in all my trucks

[Damage, Inc.]

Oil brand choice is mostly personal preference. No oil company has an 'edge' on the other, *if* you change your oil on the recommended schedule. Synthetic is mostly a waste of money. The benefits you gain are minimal.
Oil weight, however, is important. I also come from where the temps often drop below -30°. We use 10-30 in the winter and 15-40 in the summer. Never had a problem.

Your seal is going to leak until you replace it.

[Stuka]

Damage Inc: Not trying to start a argument or anything. But I have a close friend who is a engineer for a patrolium company in the phillipines. He can name off every ingredient for every oil/gasoline out there. What he tells me I beleive as I know it is truth. Castrol is not the very best...but its the best we got here in the states for dino oil.

[1BAD401]

I just switched to Mobil 1 two oil changes ago and I'm impressed. My valve train noise is less and it is much easier to start, no more little knock when I first start it up after it sits for a couple of days. I use Redline in my Camaro but at $8.99 a qt I think it will only be in the camaro. Little fact on Redline, I was using Mobil one and dyno'd my car than I changed oil to Redline and dyno'd it again and picked up 8 rwhp!! :D (same day, same temp) The Mobil 1 only had 1,000 miles on it also, I have seen this from more than one car also and have heard other guys say the same thing. I'm hooked on Mobil 1 for the Chero and Redline for the Camaro.

[ October 31, 2002, 12:58 PM: Message edited by: 1BAD401 ]

[Mike B]

I've had pretty good luck with dinosaur juice in the past,but if you research oils a bit,you will see why all the serious high performance tuners and manufacturers would not even think about putting these outdated lubricants in any engine these days.
I'm talking about real synthetics,not blends-and they are NOT a scam.
Mobil 1,Amsoil,Redline,and others have been proven time and time again to protect an engine FAR better than any old petroleum oil can.
They not only are more slippery,but flow better and faster upon startup,and most importantly don't "coke up" and sludge an engine like dino oil does.
A good example of this is on the tubocharged car I bought recently.
The passages that feed the turbo bearings are very small and when dino oil is used can actually plug up with coked oil and seize the turbo due to the extreme heat.
One of the most recommended first things to do on a used turbo car purchase is to change the oil to a synthetic if that has not been done already.
The dino oil just can't take the heat like a synthetic can.

If I had an old beater,no-I wouldn't waste the $$.
And yes,synthetic flows into places where dino oil won't-so it will find places to escape your engine easier than conventional oil will,meaning a seep may turn into a leak.
So fix your leaks.
But in an engine I care about,it's the only way to go.
After my new 401 is fully broken in,out will go the Valvoline dino oil,and in it for the rest of it's life will go Mobil 1.
I've just seen too many reports of high mileage engines pulled apart for mods(that ran synthetic oil) that looked like a fresh,sludgefree engine inside to ignore this.
I've been very resistant to give up my cheap dino oil,but finally realized I'd rather pony up the extra $$ at oil change time,rather than be rebuilding my engine again a few years down the road.
Especially with the poor oiling system of an AMC V8,synthetic is VERY cheap insurance!

Here are a couple interesting oil Faqs:

http://www.atis.net/oil_faq.html
http://www.seansa4page.com/resource/synth.html

Mike B

[Jerry Anderson]

Very interresting acticles on oils ti looks like Amsoil is the best synthetic I used it over 20 years ago but thought it was too expensive. I will continue to use Castrol GTX but next overhaul I will really consider synthetic.

Jerry

79 Golden Eagle

[CLS]

I fully agree with Mike B. I only run synthetic oil in my 1997 Grandprix. And when My engine is fully broken in on my Cherokee, I will run synthetic also.

Chris

[Damage, Inc.]

I know no one here is trying to start an argument. It's just as I said...it's personal preference or what they've seen/used in the past. As long as you stick with the recommended oil change intervals, any oil will work fine.
Proof? Dealerships. NONE of them use the same oil, but yet, somehow, those lease return vehicles seem to run 100,000+ miles. It's called changing the oil at a regular schedule. The oil won't gum/coke up if you change it.
Oil has two (technically three) purposes...lubrication and cooling. The third is the ability to clean (read burn) the combustion gases/air/fuel in the crankcase. Under normal circumstances, i.e. new oil, the oil is happy and burns/boils the waste products in the chamber. After so-many-thousand miles, the oil loses this capability and deposits build up on the internal components.

I've seen engines with 20,000 miles on them that you'd swear had 200,000 because no one changed the oil. I've also seen engines with 100,000+ miles on them that looked brand new inside because the oil was routinely changed.

And besides, if one was better than the other, wouldn't there be overwhelming automotive support?

[Rogue]

actually all fluids have 4 functions - cool, clean, lube and SEAL ;) and hydraulic fluids have a 5th - provide hydraulic action! but who cares really?

anywho - synthetic doesn't cost twice as much if you only change it half as much which you're supposed to be able to do #1 and #2 for cold weather viscosity it is definetly worth the money - all the conspiracy theorists be ****ED

[95steel]

I like valvoline. I ran it in my Commanche for 180,000 miles and pulled it apart for a new head gasket and it was perfectly clean. Not an ounce of sludge. My brother was a penzoil guy, at 100 thousand I pulled his valvecover to replace the gasket and was shocked. He changed his oil every 3000 miles religiously and that engine had seriouse sludge build up. I don't know what is best, I thought it really would not matter as long as you changed your oil every 3000 or three months. Guess it does matter. I run GTX 10/40 in my wrangler, never pulled it apart though.

[TheGossert]

In regards to fixing my leaky rear main seal, I am unable to fix it myself (I'm mechanically challenged) and a shop will charge my major dough. So, I'm content to throw-in a cheap can of oil, every now and then.

Also, I'm convinced Mobil 1 flows better in extreme low temps than petroleum based products. But, can I live with the additional leaking if I use it? Tough call.

Larry

[oddfire]

I like Royal Purple. It's a pretty color.....phil

[Jeepzilla]

I always thought Castrol was vegetable--pressed "fresh" from castor beans. Started to be used in radial aircraft engines in the 20s. Petroleum is vegetable too, I know, but from decayed ancient ferns and stuff.

[KivaKid]

The Jeep place where I had my custom carb job done said for me to change to Valvoline ( or similar) SAE 30 in my 360. He said the multi-viscosity oils tend to build up in these engines (wax, etc.), and that the 360 has plenty of torque to turn an engine with SAE 30 in Denver, CO in the winter. Any thoughts?

[ October 31, 2002, 06:18 PM: Message edited by: KivaKid ]

[turtle jim]

There seems to be more than one opinion on synthetic.oil.It DOES seem to come down to personal choice.SO,why not try it and see if you like it or not.Says on the container,Compatible with conventional oils.Shouldn't be a problem next time you change oil.

I put it(mobile 1)in my wag,and knew right away I liked it.Within 5 miles my 360 was smoother and quieter.I have since put it in my 350 Chevy PU,and(mobile 1 gear lube) in all the diffs and tcases.

It did encourage some leaks,so I fixed em.

Call the 800 number,They tell you to double the change interval.That cuts the cost in half.

I buy mine at Wal-mart,$16.99 + tax for 5 qts. works out to about $3.50 qt.Cut that in half,when(if) you double the change interval,and now it costs less than conventional oil.

Try it. If ya don't like it,switch back.

[Lindel]

Larry, if you have leaks, or burn oil, I'd advise against ANY expensive oil, be it synthetic, or whatever. You'd be throwing good money after bad, in this case.

Get your leaks fixed, or do what most of us have done, and do it your self (mechanically challenged or not, you can do this), and once you get the leaks fixed, then use what ever oil you like!

[Rande]

Be certain your seal is bad first. I had a "bad" rear seal, replaced it and fixed that leak. BUT the front seal then began to leak. Then one day I forgot to replace the oil cap after adding another quart. Magically the front oil leak was cured! The next time I checked the oil, I saw the oil cap off, oil level was good so I just replaced the oil cap and suddenly the leak re-appeared!
Ureka!
My trouble was a plugged PCV port. I replaced the PCV valve, cleaned the hoses, and cleared the port. I also installed a new oil cap. Leak is fixed!
It may well be that the rear seal was still good, just that crankcase pressure was overcoming it and squeezing the oil out the seal. The new seal was strong enough to hold the pressure and it found a new way out through the front seal.

[crispyboy]

I recently went to mobil delvac in my little VW diesel. I immediately noticed that it did run smoother when it was colder. It has a turbo and it is a PITA to change the oil. I went to 5w-40 synthetic for the turbo and extended intervals. I have heard claims of 10k in diesel and 7500 in gasoline engines. I plan on putting it in my j-20 at the next oil change interval.

[gmcarder2]

Just a side note, I worked at a GMC dealership for 3 yrs in the middle 90's and we did in fact use synthetic (mobile 1 in a Goodwrench bottle). It was what G.M. required for all new trucks, and what was recomended in the owners manuals. I guess if the manufacturers put that much research and faith in it there must be something to it.

[Drivir8]

Great stuff on oil. I was wondering if someone might go into oil weight stuff. What weight do most of you guys use? What weight is better for say you guys in the desert and those of us in cold areas? And of course, many of us have older engines with 100K miles so just some general info on how the weight effects how the oil works would be fantastic, and while your at it, what the heck do the numbers mean?
God I feel like I'm back in school.... smile.gif

[Lindel]

I'm using 20w50 at the moment, but I've also got a burned valve, at the very least, and the oil doesn't stay in the engine for very long, most of it gets burned.

If I have to rebuild the entire engine (if it's more than just the valve), then I'll start using Mobil 1, 10w30, after the break in period.

Just as a side note, I'm going to try B&M's new synthetic tranny fluid, too.

[johnwom]

One of my friends works for Royal Purple, his uncle is a co-founder of the company. His uncle was the one that created the formula. The other co-founder was the 'business guy' he hooked up with to get started.

Anyway, I've been to the plant outside of Humble, Texas and talked to the engineers there. It seems like I remember one guy there told me that the viscosity was so good that it really didn't matter that much what weight the average guy was running but was important for extremes, like racing or Alaska winters.

I do believe there is a difference in the performance of the true synthetics. That's how RP gained success in industrial markets, by sampling the oil for use in OTR trucking companies and industrial motors and then by comparing the wear in side by side engine teardowns.

I was in my buddy's office one day and saw a picture of a Fountain (I think) race boat that had RP emblazoned over half the hull. I asked my friend how much that cost them and he said not a cent. Fountain had just put it on the boat. That says a lot.

Mobil One comes from the factory in many vehicles but especially in high performance vehicles like the Porsche 911.

Whatever you do you follow regular maintenance intervals as other guys here have said.

Me personally, if The Chief didn't use oil I would go with synthetic. Since it goes through a quart every 2-3 tanks of fuel, there's no way I'm putting an expensive oil in there.

John