I've read some totally useless threads. Pointless arguing.

I'm tired of people talking about their Fords, Chevys... etc. This is Mercedes forum! We want to know about Mercedeses!!! Here are the questions for Mercedes machanincs:

---Premium is the way to go for ANY Mercedes! Which brand though? We have Kwik (formerly Texeco). Any good?

---We have Shell, and they have V-Power with cleaning additive. That's what I use right now. Any good? I've heard some bad things about Shell.

---MAIN question: Can I use Kwik (Costco, Wal-Mart type of gas) and clean with Sea Foam from time to time, instead of using Shell?

P.S. Is any cleaning agent bad for Mercedes? Sea Foam is the best in cleaning, and calims no harm to cars. Is Mercedes any different? This is my first Mercedes.



PLEASE ANSWER ALL OF THE QUESTIONS! Any RELAVANT feedback is greatly appreciated!!!

I use BP, Racetrack, Exxon, Cowboys, Chevron...whoever has the best price.

I run a 50/50 mix of 87 and 93.

I have done this on our Mercedes thru the years for over a half-million miles. I never use Seafoam or any cleaner. I have never had any ill-effects.

Gas is gas. It all comes out of the same pipeline and the various retailers add (or don't add) their additives.

I also use Supertech oil from the Walmarts. Because it's cheap and oil is oil, IMHO. I had to pull the pan off our '90 because a professional mechanic dropped a ball socket into the engine and it eventually locked up the oil pump. The inside of the engine was spotless - no sludge or buildup of any kind. The car was sixteen years old. The oil managed to stay in the bearings and even though I drove it probably two miles with ZERO oil pressure before I noticed (I heard lots of noise) the engine was not harmed. I was amazed.

Perhaps someone else can fulfill your demand to answer ALL the questions.

BTW, would you like to tell us which Mercedes Benz model you own?

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2012 E350
2006 Callaway SC560

I believe all your questions are addressed in your owners manual. I know octane is as well as the use of additives. I think there may even be a recommended brand in there too.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Most engines nowadays have knock sensors. It'll retard the timing if pre-ignition is detected. I have used regular Costco gas for years in my 280SL and the timing is set to factory specs. There is no pre-ignition. That car has no knock sensor. I suspect that the fuel dispensed is the same for regular and premium. Check your gas milage: If you use premium you should get about 2 more MPG. It's supposed to have more energy content.

WRONG!!! This is the oldest of old wives tales. Octane is a measure of knock resistance ONLY!!

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

But, for a number of reasons you still may get better mileage. This is a complex issue and there is no simple answer. That is why we have so much (anecdotal) contradictory evidence. Also, some high octane gasolines do have higher energy content.

Jl

A high compression engine will generate more power with high octane fuel than with low octane fuel, however this has nothing to do with the energy content of the fuel. If anyone would like you to belive high octane fuel has "more energy" it is the oil comanies right? Here is what Chevron has to say about it:

"Don't Buy a Higher-octane Gasoline to Improve Fuel Economy

Octane and energy content are not related. Premium-grade gasoline doesn't necessarily have a higher energy content, especially if it is oxygenated.

The exception to the above advice is when a lower-octane gasoline doesn't satisfy the octane requirement of the vehicle's engine. The abnormal combustion that announces itself as knocking reduces engine efficiency. Using a higher-octane gasoline that eliminates knocking will improve both engine performance and fuel economy.

Many newer vehicles with an electronic control module (ECM) also have a knock-sensor device. When the sensor detects knocking, the ECM retards the engine's ignition timing to eliminate the knocking. This happens so quickly that the driver never hears the knocking. But retarding timing decreases power and fuel economy. A higher-octane gasoline may improve the performance of knock sensor-equipped vehicles that have less power than when new."

I question their last statement, but they are trying to sell the stuff right? It is a classic "might" claim. "might", "might not".

Here is the link:

http://www.chevron.com/products/prodserv/fuels/bulletin/fuel_economy/

Mike

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

Pretty demanding considering you're asking strangers for free advice.

Rules of society do still apply on the internet -- in my humble opinion.

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Jeff Pierce

Current Vehicles:
'92 Mercedes 190E/2.3 (247K miles/my daily driver)
'93 Volvo 940 Turbo Wagon (263K miles/a family truckster with spunk)
'99 Kawasaki Concours
Gravely 8120
Previous Vehicles:
'85 Jeep CJ-7 w/ Fisher plow (226K miles)'93 Volvo 940 Turbo Wagon
'53 Willys-Overland Pickup
'85 Honda 750F Interceptor
'93 Nissan Quest
'89 Toyota Camry Wagon
'89 Dodge Raider
'81 Honda CB 750F Super Sport
'88 Toyota Celica
'95 Toyota Tacoma
'74 Honda CB 550F

Not all gas benzos call for premium.

My 84 500SEC used RUG. It was one of the reasons I bought it. At those prices it was fairly close to the operating cost of a diesel on the highway since Diesel costs more per gallon.

I tried to avoid a steady diet of cut rate stations and used a bottle of cleaner every five or six tanks full.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

For my gassers, I always run premium. I can tell you absolutely and definitively that *all* my gasoline cars run better on 93 octane premium in Texas as opposed to 91 octane premium in the Bay Area of California. Same brand - Chevron. I generally default to Chevron though do occasionally put a different brand in the tank. Though I use ‘off-brands’ very sparingly. I always fill the tank, regardless of brand. There may be a lot of marketing hype with Chevron, but I’ve had a couple unrelated indies recommend Chevron over the years.

I do believe gas-is-gas for the most part and basic octane levels must be the same, brand-to-brand. However, off-brands are off-brands for a reason. Not sure why, but believe they may not have the additives or purity; i.e.: moisture content, suspended solids, etc. I would be interested in reading the thoughts of others regarding this. I would imagine each of the big-guns (Chevron, Texaco, Shell, Union 76, Phillips 66, etc.) are similar in product quality. However, to my knowledge, only Chevron discusses a chemical additive (Techron) while the others (Shell, in particular) just talk about marketing slogan; i.e.: V-Power.

I choose Chevron for the quality and consistency of the product. Yes, I pay a few cents more per gallon. But even if the tank in my SL600 is bone-dry empty, a full tank is only - worse case - $2.00 more than the cheapest off-brand. And at the base price of premium today, that’s a rather small percentage of the total fuel bill. Why not pay a few cents more for quality and consistency of product? I think I can afford up to $2.00 extra per tank for peace of mind and good performance.

Every 4 tank-fills, I add a can of Techron, even if I've been filling with Chevron. I like the cleaning ability of Techron and, according to the Factory Approved Service Products (as of) September 2006, page 15, Mercedes now authorizes one of two gasoline additives – MB product p/n: 000.989.25.45.12 or Techron Concentrate Plus Fuel System Cleaner (588 ml, 20 fl oz container). I track my MPG carefully for all my vehicles and I do see an MPG jump of 1-2 MPG immediately upon adding the Techron additive. Each tank-fill after that, the MPG drops a little. After 4 tanks, I repeat the process. My plugs come out clean and using a bore-scope shows very clean cylinders and piston heads on the SL’s. (Haven’t changed the plugs yet in the ML.) I believe the Techron does help – it’s not a wonder cure-all and it won’t instantly make your car a Batmobile, but over time the product does have a positive effect.

I have not used SeaFoam… yet. However based upon threads in this forum, I purchased a can of SeaFoam but have not used it yet. I have used other additives over the years, some with dubious or marginal success. I always seem to come back to Techron.

BTW – I do not work for Chevron; never have. In my professional career I managed high-tech engineering organizations – no affiliation with the auto industry, other than a love for Mercedes motorcars.

Cheers,
Jeff

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MBCA Member #B012089 (Lone Star Section)
OBK Member #47 (W123 Division)
'96 SL600 (105K) Triple Black - Mein über-Fräulein
'79 240D (292K) Yellow/Saddle - Mein Spielzeug
'01 ML430 (123K) Black/Saddle - Wife's Ride
'94 SL500 (164K) Green/Champagne - Daughter's Dream
'73 450SL - RIP
'86 300E - RIP
'88 420SEL - SOLD
'94 S320 - SOLD

I've run 93 octane Shell premium on all of my vehicles since ownership...no fuel related issues as far as I can tell. When I do travel further north, 91 octane is the highest available and I use that.

And octane is a measure of "flash point", not energy content or anything else. Translated, it takes a higher temperature to ignite the atomized fuel in the combustion chamber. That means, it won't "pre-ignite" in the compression cycle or "knock" as what it is normally referred to.

This is why turbo gas engines require premium.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

It's not about temperature. It's about compression. Higher octane means it needs more compression to ignite without a spark (pre-ignite). Using higher or lower octane depens on engine compression relation and hight above sea level. You need high octane when at sea level and can use (or mix) lower octane on high locations. Engines with compression relations under 10:1 usually work good with regular fuel.

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter

Higher temperature is caused by Higher pressure. That's how diesel engines work.

They compress the fuel until it is hot enough to ignite. So really, it is about temperature.

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2012 E350
2006 Callaway SC560

I have a 1986 560 SEL with 156K miles. This car has had nothing but regular unleaded fuel and it runs fine, gets decent mileage and has had no engine problems. That being said, if you drive your MB hard and fast or pull a trailer or do things that put the engine under heavy load, premium fuel is the way to go. But for normal everyday driving you can use regular unleaded.

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1986 560 SEL (159K miles)

Uh...don't think so... I believe only the air is compressed in a diesel, and then fuel is injected. In a gas engine, the air-fuel mixture is all compressed, then the spark plug fires. Someone correct me if I'm wrong, but I seem to recall this being one of the main differences between the two types of combustion and fuels.

Cheers, John

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'98 E300TD (W210) | Sold 6/09 with 205k and counting
'04 VW Touareg V10TDI