Here is the blog post in question:

http://www.stephensservice.com/bluet...ssuesproblems/

My dream car is a 2012-2013 Mercedes S350 diesel, but I am not an expert about these issues, so I'm really conflicted here. I am quite willing to buy used parts, even buy a used engine eventually to keep it in working order, but I read a blog post by an ex-Mercedes mechanic that absolutely said this engine (in particular the mercedes version in the S350) is a disaster zone in terms of design and complying with restrictive US EPA regulations and unwise engine oil requirements promoting fuel efficiency over longevity. He says 5W30 oil is absolutely the wrong oil in most climates, unless it's literally subzero all the time (I live in Houston).

He also said the 10,000 mile oil change interval is entirely inadequate for these engines due to excessive heat associated with the turbo which gets fed directly into the engine oil (8.5 quarts capacity is actually worse because it heats up faster). He claims the diesel fuel mixes with the relatively thin oil and this allows the hot oil to cause major problems for the engine over time that just get progressively worse with age (due in part to vaporization). The only oil he recommends for OM642 engines is high weight motorcycle oil, like Amsoil. He says nothing else can withstand the intense heat, and even then, the proper oil interval is 5000 miles maximum. This oil tends to also be very expensive, but if it's protecting my engine it's arguably worth it. He also said, do not disable the bluetec system.

One possibility I'm considering is only buying a car that has been in California's mild climate it's entire life and been driven mainly as a highway cruiser, because the short stop and go abuse that most cars are subjected to is entirely unsuitable for this engine and the recommended oil and change interval. I know there are people who have owned these cars and haven't had any sort of major problems. I know a guy in New York that operates one of these vehicles as a luxury limo outside of New York and has 300,000 miles on his engine, so there's got to be a way to efficiently care for this car in a way that is economical if he's operating a business with one. Please convince me this isn't the worst decision I've ever make in terms of a used car.

Thank you.

 

Bought my 2011 with 47k. Had 2 Dealer Services that were pretty bad experiences...Along with a warranty repairs.

Rear Airmatic, Airmatic Compressor 100% will need to be replaced with Arnott Stuff.

I personally switched to the 20W-60 Redline around 66k-ish, after my last Dealer Service...which used a 15w-50 at 56k when my Oil Cooler got changed...put 10k on that Oil, car was rattling sounded terrible.

I found Stevens site, around I started getting really into the Oil stuff. I think it REALLY matters, combined with keeping the intake manifold\pvc clean. I went Redline after a Liqui Moly Flush.

Going to change it next again week with around 3,000...going out for Oil Sample to check for metal levels.

I'm going to swap it for Fresh after another LM flush and adding LM Ceratec to the 20W60 Redline.

If you are going to buy one, you better have the ENTIRE Maintainance\Warranty Service History and have it checked by a Trusted Indy before purchase.

The problem is most of these cars start off as Leases, and get a 8-12k on the oil changes if they are lucky. The oil is diluted by diesel and soot-filled...then shot back into the Turbo by the PCV system.

Also doing a Hydrogen Intake Carbon Cleaning and a Fuel System Flush w LM Diesel Cleaner, because It's getting slow to startup. After that I will start using LM Diesel Additive every other tank.

The Redline Oil already makes the car sound a MILLION times better. I get a 'slight' rattle for a half-second at cold-start but immediately goes away, like half a second. It could be because the cold-flow of the 20W-60, I'm curious to see if the Ceratec makes that go away.

I'm prepared to do a Preventative Timing Chain around 75-80k if the oil numbers don't look good.

I will probably make a full thread on my finding after I put some miles on the Ceratec\Redline Combo.

 

Thanks, keep us updated. I'd really like to send a sample of the oil off for an oil analysis before I buy one, but that may be unrealistic.

 

You're going to have to assume any car you buy is going to have the oil under changed...the Mercedes 1-yr Maintenance Schedule is the culprit.

If you get one, look for one that's had the Oil Cooler and all the Bluetec stuff that's gonna break...changed already. Then just be really on-top of preventative maintenance.

Listening for the rattle on cold-start is a big one...there's an updated part number for the tensioner, so they are probably flawed.

If you could pre-negotiate the Updated Oil Seals, Updated Tensioner, and an Intake Manifold Cleaning before you buy...then swap the Mercedes Airmatic stuff for Arnott lifetime Warranty when they go out.

You should have a pretty solid car...I love mine (When it's not costing me $$$, lol)

 

I would really appreciate if some one would post oil analysis results of running om642 on motorcycle 20w60 oil.
Thanks

 

My independent mech said the same . No blutech and definitely no BMW 7 series out of warranty . Lol
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He's a highly rated independent, that works on European vehicles..

 

How many Bluetec motors has he worked on 500 of them? Lol, he works on McLaren makes him a reputable mechanic, you realize that's an english car right? Any mechanic who says or believes the English make good cars (outside of England) or even the Italians I would steer clear of.

 

this kind of response is why this forum is dead..I don't have to justify anything to you.But he's worked on all of my BMWs he works on my Range Rover he will work on my Mercedes when it's out of warranty. I'm just passing along what he told me go look up the problems with the BMW 7 .. Or make a big post talking about how awesome you are. Lol.

See below.

 

You definitely do not need to, its your money, burn it as you would like. Good news is I dont need to look up anything, as I have been playing and obessing with cars since I was 18 (not just reading the newest Car and Driver), my 20 years of mechanical engineering experiences tells me most of what I need to know on a high level. BMW turbo cars with Direct Injection are garbage, they fowl and have massive carbon build up in the heads around the valves. I would never own one, the last great BMW worth owning was the 3.0 I6 motored 330.

The fact you own a Range Rover and would buy one is all I needed to know. I will take your car advice with a grain of salt. You realize Range Rover has the most defects per car of any car maker right? Yet you want to inform people not to buy a Bluetec Diesel. Enjoy in good health!

 

Get over yourself.

 

Range Rover break down yet? Lol. Stop passing bad info like you know about cars when you just show up and buy whats in the magazine

 

​​​​​​Do you cry in real life this often?

 

When did MB updated part number for the tensioner for OM642 engines?

 

 

You should try posting something constructive instead of starting fights all the time.

 

often people with low self-esteem feel like they have something to prove, as is just the case with buddy.
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Oh I do, feel free to look at my posts (Back up camera, BG245). I don't appreciate people putting down something when they have no idea, or use a non statistically relevant sample sets to push others to make the same opinion. Not to mention, they don't wrench on the car or own one. Where is the OM642 you own again? Calling it a bad motor is your opinion and as such I am entitled to mine and proving my point, sorry you don't like it. Same goes for your Range Rover friend in this thread he doesn't even own an OM642, he doesnt work on his own cars, but speaks the opinion of his English car mechanic like its the gospel. The OM642 is the preferred motor of Europe and has been proven durable time and time again. If the problems were as rampant as people like yourself like to make out, there would have been a class action suit long ago in Europe and the US. Much like was done on my W211 M156 for soft cam shafts and lose head bolts. Show me a statistically relevant number of failures where the owner couldn't be found at fault and its 100% engineering related that would justify a class action for the OM642. Until then I will push against all these posts.

 

You make a lot of ***umptions.

The more you talk the more you come across like an ignorant *****.

But please,carry on champ.

 

 

LOL. Are you really still crying?

What would your wife's boyfriend think of the way you're acting on here? Grow up..

 

Lol, from the guy who owns a Range Rover, keep up the peacocking! You keep responding, maybe you should let it die, but you are entitled to your opinion. Still no facts from you yet, imagine that, no facts from a Range Rover owner. I need to grow up, yet you and your bestie make claims that you cant back up in any way shape or form. Go post in the Range Rover form or the CL550 form BUH BYE

 

Rent free
You do realize you're freaking out on an internet Forum because some mechanic told me to stay away from Blutech and 7 Series Beamers?
Show me where the Range Rover touched you, lol.

 

 

You seem to have deep-seated emotional issues and although I stayed at a Holiday Inn last night I'm sorry I can't help you.