Synthetic or Regular Oil ???

[kythri]

And I thought I was the only one

Both Walmarts around me kick the *&^% out of any automotive store in my area in terms of chemicals.

That's where I buy my Mobil 1...

Still have to get the filters from AutoZone, because Wal-Mart doesn't carry Mobil 1 filters...

 

[Mike83]

Audi's and BMW's:

Synthetic, change once a year, every 12,000 miles or whenever the car tells me to take it to the shop. Why, because that is what the dealer tells me to do. They are under warranty so why should I care?

I would care because when the warranty expires I would be stuck with the engine, whether I treated it nice or treated it like ****. Not saying you do either, but that is why I would care.

 

[jerk_chicken]

Yeah, you should see the insides of those engines run on those intervals.

 

[Major Ramifications]

The only time I use synthetic is if it is on sale or has a rebate making it as cheap or cheaper than organic oil. I usually use synthetic blend usually in the wife's minivan, since the reccommended oil change interval is 5,000 miles. On my car, the owner's manual says that I should change the oil every three months, regardless of the mileage. Kinda ***** when I only put 6,000 miles on the car per year.

On the Wal Mart subject, Richard Ehrenberg (Tech Editor of Mopar Action magazine) said, I buy my oil and filters at Walmart, doesn't everybody?"
I used to, but I haven't done it in a while.

 

[Major Ramifications]

Audi's and BMW's:

Synthetic, change once a year, every 12,000 miles or whenever the car tells me to take it to the shop. Why, because that is what the dealer tells me to do. They are under warranty so why should I care?

But will they honor the warranty if you only change the oil once a year?

 

[autoace]

Mobil 1
13,000 miles between oil changes if it needs it or not....

RP

That's too long, the oil may not break down per say, but the contamination is heavy and filter integrity are long since gone by then.

 

[autoace]

You make a lot of good points, but it depends on your usage and area.

Here we use semi-synthetic or synthetic because hereabouts your ambient temperature hits 150. That's the actual air temp your car ***** in above the pavement. The shade temp is say 115 or 118.
Since you need 5-20 oil both because of the need to lube your cams on startup and the need for better fuel mileage from less oil drag.
The synthetic oils hold up much better at these weights under these conditions.

Also, if you experience failures, say blow a radiator hose or lose a fan switch, the synthetic will handle the heat increase much better, giving you at least a fighting chance of saving a 3-7 thousand dollar motor.
I haven’t bought a new car in many years that DIDN'T require synthetic, at least a blend, to maintain warranty.

Good points, but I think the biggest problem is with consumers not being informed. How many times have you seen someone thinking they are doing an old high mileage car (like a 1992 Volvo 240) a favor by using synthetic oil. Half the time the engine develops leaks, and the old tappets get noisy.

If someone has a 2006 Volvo 2.4 Turbo, synthetic should be used from day one(aluminum block, turbo heat, small internal oil passages) there is a case where conventional oil, especially of the wrong weight will do more harm.

IMO it completely depends on application, but with most non-turbo cars, in moderate climates I don't think synthetic is necessary, unless dictated by the manufacturer.

Here is a "funny"...I had a guy come into the shop, I was changing oil on an old International diesel. As I was pouring the last 4qt. container of Mobil Delvac into the engine he says........................amazing you don't have to change that for one million miles..no he wasn't being humorous....he said once a year he just changed his filter and topped it up

 

[walrus]

I run Mobil 1 in everything I own. Change my service truck between 8 and 10000 miles. My wifes honda at about 6000, she short trips more than I do. I even put it in my 57 ford tractor, the oil pressure comes up quicker when I use it to plow on cold winter mornings

I've heard of fleet cars going 25,000 on Mobil 1, changing the filters at 5,000 and then adding makeup oil.

I buy the Mobil 1 at Sams Club, the price has gone thru the roof

 

[autoace]

Mobil even has extended performance oil (15,000) miles. Remember the oil companies want your money, they don't really care how long your engine lasts.

Additives are even worse, in many cases,i.e. Lucas trans. treatment...I've had customers use this stuff, in cold weather it is soo thick it doesn't come out of the pan.

Anyway I had an oil sales rep. that came to my old garage. Did you know Mobil 5000 "conventional" is really synthetic blend? That is why Mobil doesn't make a "semi-synthetic".

My advice to everyone is not to let your oil changes run over 6000(city) or 7500(mostly freeway) even with synthetic oil. I have rebuilt alot of SAAB 2.3 turbo engines that really looked like pitted ****, using synthetic and only changing at 10 to 11K miles.

Remember to use a good oil filter, Mobil 1 with a junk FRAM oil filter is much worse than conventional Valvoline with a Wix gold filter.

 

[WSMC633]

In my daily driver truck, I usually run Conv. oil, K&N filter and change every 3000-3500 miles. BMW with Supercharger I always run Synthetic.

In my Racebike I run Repsol Full Synthetic w/ K&N filter and Change it every 2 trips to the track. So basically once a month - or 300 miles. Last time I took the head off the motor it looked awesome in there.

 

[Delray]

I have been using Amsoil for about three years. It's pretty cold here in the winter and the motors start easier and come up to pressure quicker. I had been using Havoline previously with good results but I had been changing it every 2,000 to 3,000 miles and that was getting old especially in the winter. I put on close to 50,000 miles a year between personal and route vehicles. I change the synthetic between 10,000 and 12,000 and replace the filter once or twice between changes with Wix brand. I never had an oil related engine failure either with Havoline or with Amsoil. I also believe fuel mileage improved with synthetic oil but it was a very slight improvement.

 

[v8garage]

Synthetic may be the way to go for a new engine and then continue to use it. I tried it on a 4.6 Ford engine that already had 110,00 miles on it. It made it start using oil. It had been using a quart every 1400 miles and with synthetic it used a quart every 700 miles. Switched back to conventional oil and it went back to 1400 miles per quart. Both oils were 10W40.
V/8

 

[Senorpablo]

Waste of money in my opinion.

As Autoace says, be very careful about switching from non to synthetic on a high mile car. Additionally, switching from synthetic to non-synthetic can be problematic. Seals shrink with synthetic and you'll develop oil leaks.

 

[DHS]

My S10 has 200,000 on a 2.8. I bought it cheap with 100,000 with a knock/rattle with any oil lighter than 50wt. I have always used Valvoline racing 50wt changed at 3500 miles. If and when she goes I will run 10w40, but with a lite foot I hope to get another 100,000 out of her first.

 

[jerk_chicken]

Waste of money in my opinion.

As Autoace says, be very careful about switching from non to synthetic on a high mile car. Additionally, switching from synthetic to non-synthetic can be problematic. Seals shrink with synthetic and you'll develop oil leaks.

I have personally swapped six high mileage cars over, with no adverse effects, leaking, burning, or otherwise.

 

[Titus]

I use Mobile 1 Full Synthetic 5w30 in all my cars.

The practice started with my Miata (that I have owned for 8 years now). It is common for Miatas to have noisy HLAs, and my Miata suffered from this when I got it. With regular 10w40, the HLAs would start making noise for a few minutes at start up with-in 500 miles of an oil change. I switched to 5w30, and it would last 750 miles before they were noisy. I then switched to a 5w30 syn blend, and would get about 2000 miles before it would get noisy. I then switched to the Mobile 1 5w30, and it will go about 3500 miles before getting noisy. The car is only driven about 7k miles a year, so this is an acceptable interval for me. I now make a habit of changing the oil as soon as the HLAs start clicking.

My wife drives a MINI Cooper S, and it requires 5x30 Synthetic. It just makes sense then to give it the same Mobile 1 that the Miata gets. BMW recommends oil changes for the MINI every 20k miles, but I have a hard time going that long. I went 7500 before the first oil change by me and I will probably stick with that interval.

We also own 2 project cars that are both getting Miata drivetrains, so they will get the Mobile 1 too.

 

[kythri]

I can't find the reference, but I read somewhere that the seal shrinkage/synthetic causing leaks in high mileage engines was a fallacy.

I converted my Explorer over before it hit 100K, and my Vic isn't there yet, so not really "high mileage", but I haven't seen any leaks.

A friend of mine started running Mobil 1 in his Bronco 2 with nearly 200K on it, no leaks either, after about another 15K on it.

 

[Identaltech]

I use synthetic because of cold weather start up and oil looks cleaner after oil change compared to dino oil. some of the vacuum pumps we use never have oil change and only use synthetic oil only and they run for 20 years.

 

[speed bump]

We run Max life in everything and I have never found any new leaks putting it in after buying vehicles that had previously had dino oil in them even 40 year old FE engines. Haven't had any extra noise even when running 5w-30 in them in the winter either.

The 2 biggest advantages I have found to running synthetic especially in really hard running engines are.
1.) Its start a whole lot easier when its below 0°F than Conventional oil
2.) If you are running it on the highway after about an hour you start loosing some oil pressure with conventional where as the Max life stays steady and you loose a whole lot less oil pressure when you pull off the highway with that versus conventional.

 

[RickP330]

That's too long, the oil may not break down per say, but the contamination is heavy and filter integrity are long since gone by then.

Even with a fleece filter?

I don't think so...

RP

 

[Major Ramifications]

I was in WalMart this morning, and I noticed that the price gap between the organic and synthetic oils is much smaller than it used to be. They had Castrol full synthetic for $17 per 5 quart bottle. About what the regular oil cost per quart.

 

[Coach James]

Regular oil was $17 a quart?

Coach

 

[Major Ramifications]

Regular oil was $17 a quart?

Coach

No, that comes to $3.40 per quart, which is about what the regular oil costs if you buy it by the quart. Sorry if my wording was not clear.

 

[Scotto]

WOW, there's a lot of misinformation in this thread.

The ONLY way to know if your oil is working good in YOUR engine is to get a used oil analysis done. It'll tell you if there's additives left in the oil, if the viscosity has gone down after use, if you need to clean your air filter, if you have coolant in your oil, etc.
I get mine done at http://www.blackstone-labs.com

And just comparing synthetics to dino oil isn't everything. There's difference in quality between brands/weights and they will all work differently in different engines.

I personally run "German" Castrol GTX 0w-30. After 5k miles it has a much higher viscosity in my WRX then regular GTX 5w-30 after 3k miles. The turbo is really hard on the oil. And the regular GTX held up better then Mobil1 5w-30 for me (both at 3k miles). But every car's different.

If you REALLY want to learn about oil, check out http://www.bobistheoilguy.com/forums/ubbthreads.php

 

[Danglerb]

All this oil chatter, can anybody tell me of ONE case where substandard oil caused a failure when changed at the recommended intervals?

Most wear in engines is due to air filters.

Shell Rotella T about $10 a gallon at Walmart.

 

[Scotto]

All this oil chatter, can anybody tell me of ONE case where substandard oil caused a failure when changed at the recommended intervals?

I know a couple guys with WRXs who ran Mobil1 5w-30. The stuff thinned to a 15 or 20 weight within 3-5k miles and took out some bearings.

In most cars you wouldn't have that kind of viscosity breakdown, but you should be aware that it can happen.