AMSOIL synthetic for diesels

Does anyone have experience using AMSOIL synthetic for their diesel cars? Amsoil website lists a lot of good attributes vs. other synthetics. I currently use Mobil 1.

thanks-Raj

Reply to
gator_mech
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A friend of mine does. He's a farmer and used amsoil in his very very expensive farm equopment. He tired it in his car(s) and despite NOT being a dealer, raves about the stuff.

Reply to
Richard Sexton

You can also use Shell Rotella T Synthetic 5w40... they are available at Wal-Mart for $3.99 a quart... sold in gallon container. I just picked up two bottles. In October, they will have newer oil that meets CJ-4 rating for

2007 engines.

Right now, they are CI-4Plus... which is the highest availble now. I am currently using Mobil 1 Truck & SUV 5w40... which is the ONLY Mobil 1 oil designed for Diesel engine. You can get Delvac Synthetic but are hard to find and super expensive. As far as I know... Delvac Synthetic and SUV oil is the same.

At this time, Shell RotellaT Synthetic is the best deal.

Reply to
Tiger

I will be using Amsoil synthetic stuff in all my cars... Mobil 1 prices are super high now at $5.69 a quart... that it makes sense to go Amsoil.

Reply to
Tiger

I have been a Mobil 1 user for just under 30 years and recently switched to Amsoil after doing some research. Mobil 1 was at one time, I believe, a true 100% synthetic oil, but has reformulated their product by doing something called "hydro-cracking." It leaves you with a good product for lubrication, but it does not maintain the same quality over the long haul as a true synthetic.

Amsoil is one of only two 100% synthetic oils on the market and the company makes no bones about sharing its test results with you. Mobil, on the other hand, uses all sorts of marketing terminology that are at best, technically non-specific, and at worst, misleading.

The only thing I don't like about Amsoil is their marketing approach. You can rarely find Amsoil at a retail outlet and must usually purchase through one of their representatives. To be fair, I believe this is due to the fact that most retailers don't want to sell an oil that is capable of oil change intervals far in excess of conventional motor oils. The retailer cannot sell nearly as much oil if their customers are using Amsoil.

I don't want to waste your time going on about the value of TRUE 100% synthetic motor oil, but I recommend it highly. If you have any further questions, I would be happy to answer them. However, I have found the Amsoil website to be one of the best manners of education available.

If you want to learn more even outside of the Amsoil site, there is another great site about synthetic oils by a company called Synlube. It is extraordinarily expensive product, but I have found its claims to be true. It is not practical for diesels as the soot factor mandates one change the oil long before its lubrication qualities are exhausted.

Hope this helps.

Tom

gator_mech wrote:

Reply to
Tom

Tom:

Thanks for the detailed info. I had used Amsoil in my Mazda RX-7 years back and amazingly it got about 10% better mileage. I still find it hard to believe Amsoil can reduce friction by such a significant amount, but it did. Have you noticed this in your MB diesel also?

Do you feel it is safe to extend the drain interval to 15,000 miles, or once a year, as recommended? Do you use a 3 micron bypass oil filter to keep the oil clean? I hear truckers change oil once in 25K miles, with oil analysis. I do plan to switch to Amsoil from Mobil 1 from my next change.

I live in Florida. What weight do you recommend, 5W40 or 15W40, for my 1999 E300 TD?

Do you purchase Amsoil by mailorder or thro' a dealer?

Thanks-Raj

Reply to
gator_mech

The selling point of synthetic oils is that they're more resistant to breakdown from high temperatures than dino oils are. However, the reason diesels generally have shorter oil-change intervals than gaso- line engines isn't thermal breakdown; it's because the oil gets dirty a lot faster.

I run Mobil 1 or Castrol Syntec in my 300D 2.5, but I change it every

4,000 miles just like I would dino oil.

Geoff

Reply to
Geoff Miller

That is a waste of oil... but the oil you use is not designed for Diesel engine... take a look... there is no CI4 rating or anything about diesel.

Stick to Mobil 1 Truck & SUV 5w40 or Shell RotellaT Synthetic 5w40 (much cheaper). Or go Amsoil.

On newer diesel, change interval is 7500 miles or so...

Reply to
Tiger
[I said I change my oil every 4,000 miles]

Well, what oil change interval would you recommend for a '91 300D

2.5 with 107,000 miles on it, then?

Anecdotally, five thousand miles between oil changes seems to be a common interval with gasoline engines (and easy to keep track of, to boot), so I figure knocking a thousand miless off of that in the case of a diesel is rational.

(Wasn't a *three*-thousand-mile oil change interval recommended for the W115 240D and 300D back in the '70s? I seem to remember reading that in one of the car mags way back when...or "back in the day," as the kids like to say.)

I'll look for 'em -- thanks -- but it's damned near impossible to find my preferred grade of Mobil 1 (15W-50? something like that) as it is. I don't think I'v ever seen "diesel rated" motor oil of any brand for sale in my entire driving life. Maybe it's in the fine print.

Geoff

Reply to
Geoff Miller

Look in your manual... it would say for regular oil at 7500 miles... but that is not recommended by diesel purists. With synthetic, I would go 7500 miles. If you do not want to use synthetic, then 3000 miles is what I would recommends.

The old days with regular oil... 3000 miles is recommended. Modern engine now burns so much cleaner so oil change interval is much higher.

Diesel rated synthetics starts with 5W... regular diesel oil starts with

15W. Walmart has Shell RotellaT Synthetic Oil in dark blue gallon container... $3.99 a quart price... so you are paying $15.96 per gallon.

Diesel rated oil has better property to keep the soot in suspension and control while regular oil or non-diesel synthetic do not have those properties. Diesel engine also have much lower RPM and temperature operating condition so diesel oil is not recommended for high performance gas engine.

The highest rated diesel oil is now CI4 Plus... CJ is coming in winter. If you look at regular oil, you will see like CH or CF rating instead. CI4 is designed for diesel car with EGR system... or otherwise the EGR will clog up.

Gas engine now for MB now has 10000 miles interval with Synthetic oil. Older MB had 7500 miles with regular oil... and the two decades ago would ask 5000 miles... The main thing is engine has changed so much that it ran so much cleaner.

Reply to
Tiger

Yes. Here is some more info on oils for diesel.

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For direct contact replace nospam with schmetterling

Reply to
Dori A Schmetterling

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