Is 0w-40 always better than 5w-, 10w,- and 15w-40?

[Garak]

Originally Posted By: OVERKILL
There are approved 0w-40 lubricants for 18-wheeler applications and I gave an example of one. Simply because Mobil doesn't list HTHS for it or their 5w-40 isn't really relevant to that point. They are still approved.

And, in the same product line, there are 5w-30 and 0w-30 products with CJ-4 approvals, with an HTHS of 3.5 or great, too.

friendly_jacek: The HTHS of Delvac 1 ESP 5w-40 is quite likely 4.0 or above, at least from what I've derived in a few discussions. It is not the same product as the retail M1 TDT 5w-40. Addition to Overkill's point about costs, in this neck of the woods, HDEOs, by they synthetic or conventional, can be obtained rather cheaply. The Delvac 1 I use in my G37 is not only a great product, it's priced from the distributor about the same as conventional is at retail here.

 

[Teddyen]

Ok, so the only thing holding me back from buying the M1 0w-40 New Life, is Ramblejam's advice of Mobil Super 2000 10w-40. He's given some hints that he knows my engine well and what's best for it, but at the same time, I haven't gotten any kind of explanation from anyone that justifies that the semi-synthetic Mobil Super 2000 10w-40 will be better than the M1 0w-40 New Life.

The Mobil Super 2000 10w-40 has more P (0.144), which I guess means that the ZDDP-values are around 1400ppm (?), compared to the M1 0w-40's 1000ppm. If this is important, I could just add some ZDDPlus to the M1, if you guys mean that the M1 0w-40 actually can be improved upon.

The reason I want to try 0w-40 instead of 10w-40, is because my impression is that the M1 have a higher chance of keeping the oil tubes under the valve cover clean (which can be big problem on my engine), and also simply because very many people recommend it and it seems like an overall very good oil. M1 also recommends the 0w-40 to my car.

The reson I don't want to try the 0w-40, is the lower ZDDP-levels compared to the 10w-40. I'm also slightly afraid that with a thinner oil when cold, more oil will drain out of the tensioner overnight, which contributes to chain slap on startup. It was also never a factory recommendation, but I guess that 0w-40 oils probably didn't exist in 1990, which may explain that?

On the other side, maybe all of this is just crazy to spend time on at all, and that it makes little difference which of these Mobil oils I choose, as long as I'm aware of my engine's quirks.

 

[Ramblejam]

Hi again, Teddyen -- sorry for the delay in response. Started to write out a lengthy reply, but quick question first: Is Mobil the only product that's available to you locally at a fair price? Any other options?

 

[GuillaumeG]

For the diesel engines - at least modern ones, there comes two things : Oil has to be more detergent, because it has to clean soot, and oil must burn without making too much ashes because of particulate filters.

 

[Teddyen]

Originally Posted By: Ramblejam
Hi again, Teddyen -- sorry for the delay in response. Started to write out a lengthy reply, but quick question first: Is Mobil the only product that's available to you locally at a fair price? Any other options?



No problem at all, I'm very happy for every bit of help I can get.

Apart from M1, I can also get Castrol (Edge, Magnatec, GTX), Valvoline, Techtron, Shell, Total and Comma. Cost isn't really a factor, as they're all pretty expensive, and the big brands aren't far from each other. Pennzoil is hard to get, but some racing shops have it.

 

[Ramblejam]

Originally Posted By: Teddyen
What would you do to remedy this bad habit of the 420?


1. Know your engine.
-- You've certainly demonstrated a willingness to learn about M116, and I happily applaud that with enthusiasm! It's great to see someone dive-in and learn.

2. Realize that no oil is a cover for mechanical maladies.
-- You seem to have things squared away and operating appropriately, so we're good here.

3. Use the appropriate product
-- More on that...

Originally Posted By: Teddyen
I haven't gotten any kind of explanation from anyone that justifies that the semi-synthetic Mobil Super 2000 10w-40 will be better than the M1 0w-40 New Life.


It was actually the "Formula P" version of that product that I was interested in -- rather enthralled with the idea of something like that being available on the local store shelf. However, while in the European market, it hasn't made it to Norway, so it's really a moot point after all.

As for the 0w part of the equation, it's my position that you're myopically focusing on but one aspect of lubrication. Yes, theoretically speaking, you want something that's as thin as possible during start-up to minimize wear. However, real world usage demonstrates that there are several other variables we need to be concerned with, and you have to look at the product as a whole (in conjunction with the needs of your application) to determine suitability.

Originally Posted By: Teddyen
A (not so) fun fact: a qt of 0w-40 New Life costs $36 at gas stations in Norway. A gallon costs $70 at the cheapest store.


Mobil 1 is undoubtedly an excellent product. As a matter of fact, I utilize it in most of my applications due to the outstanding performance I've received (via UOA), and broad market availability/low cost. However, when we're looking at $70/gallon acquisition, and a car that uses 8.5 quarts, things change -- at that price point, we're talking oil changes that are quickly approaching $200 (two gallons, filter, makeup oil). Again, we're dealing with an exceptional product, but that's absurd. Furthermore, there's no data to indicate that longer drain intervals can be utilized here to offset cost, and that only increases my resistance to put it to use.

Given everything we know, here's my best selection:
http://www.mobil.no/Norway-Norwegian-LCW...-esp-15w40.aspx

- 15w products are approved by Mercedes down to -15°C
- Available in your market at prices that should be far more attractive than Mobil 1
- Appropriate viscosity (15cSt @ 100ºC) and excellent additive package (Trimer)
- Will provide superb wear protection and cleanliness

 

[Teddyen]

Thanks for a long and in-depth answer! I really enjoy reading up on my car, and even the time I spend reading about oils. I'm 25, educated as an industrial design engineer, but work as a photographer and graphic designer. I guess that some part of me craves to get back into engineering.

I regret posting the price of the M1, as it was misleading. Everything is expensive in Norway, but we also have relatively high wages. A regular beer at the pub costs $10, fuel is $8 per gallon (15nok/l), and even the 15w-40 Delvac oil is close to $60 per gallon. The $70 for the M1 0w-40 is actually a fair price here, it's the $36/qt price at the gas station that is ridiculous. The new Ford Mustang V8 costs 1 220 000kr here, or $164 719. I paid $8500 for my 420SE, and in total I've spent around $14000 on it. I have to work about half a day as a freelance photographer to pay for the M1 oilchange.

Would you still recommend the 15w-40 over the M1, when the price difference is so small?

I've also understood your point about not being overly focused on the viscosity. That's also why I started this thread, to learn more, and I've now also learnt that HTHS values and VII breakdown matters.

 

[Benzadmiral]

Teddyen,

From 1999 to 2004 I drove, happily, a Benz with the same engine as yours, though my sedan was the long-wheelbase version. It was, as you might guess, the reason for my screen name. In Denver, CO, which is hardly a severe climate compared to yours, I ran 10W-30 conventional Valvoline in the winter and 20W-50 in the summer (this was long before I came to BITOG); and back here in the heat-stunned Swamp, I switched to 15W-40 HDEO. With 3-4K mile changes, the 420SEL ran beautifully on all of it. Late in my ownership, when I had to have a dented and cracked oil pan replaced, my mechanic said the internals looked clean as the proverbial whistle. (The car was totaled at 198K miles while parked, by a probably drunk and cell-phone-yakking driver. I miss the car still. It was like having a favorite dog put to sleep at far too young an age.)

So almost any oil recommended by MB for your temperature range will let the big Benz run as long as you want it to.

Post a picture or two when you can.

 

[Teddyen]

Thanks for your input, sorry to hear about your car being totaled while parked.

I would have flipped crazy guerilla on the driver.

I just cut through and ordered 10l of M1 0w-40 New Life. If it doesn't help on the valve chatter (which I doubt), I'll try the Delvac 15w-40 next change, if the valvetrain isn't already shot by then. When I bought it, there was a rather distinct tick that phased in and out when the engine was warm, now it's more muffled, and just general valve chatter. It's still phasing in and out every few seconds though, it's far from completely constant, and almost totally quiet when cold. I don't know if the guy that installed the cams and rockers for the previous owner was competent, but he had at least some interest in the w126s.

Here is a few pics, the second is from our constitution day, which we celebrate like nothing else here in Norway. I look slightly crazy with the tilted glasses, but heck.

 

[Quattro Pete]

Very nice! Love that body style.

 

[friendly_jacek]

Originally Posted By: Teddyen

wow, is this a professional shot? almost perfect except for that long shadow and crack on the ground.

 

[Teddyen]

Thanks for your kind words! Well, I've worked quite a lot with car photography, but it's just a personal shot from a day I was scouting locations for a client.

Not to go completely off-topic, this is my website: www.teodortomter.no

 

[Ramblejam]

Originally Posted By: Teddyen
I just cut through and ordered 10l of M1 0w-40 New Life.


Wow -- I'm geninuely surprised you're unable to source MX ESP 15w-40 for less, at least relatively speaking vs. Mobil 1.

With that in mind, is it too late to change your order? Notwithstanding the experience of BenzAdmiral, the additional viscosity (even though it will undoubtedly shear down somewhat -- falling back to around MX ESP) of Peak Life 5w-50 would be welcome in your application.

 

[Teddyen]

I can send an email and change the order right away, eventually, I'd always manage to sell the M1 0w-40 for about the same price as I bought it. It will probably ship in a few hours. Eventually, I can just run the M1 0w-40 for a couple of thousand miles, and then make another oil change, hopefully before the 0w-40 shears down too much. I think the PO probably ran a little long OCIs, so I don't mind even another short change interval.

5w-50 Peak Life was actually one of the first oils I considered, as the higher viscosity (and now I've learnt, also higher HTHS) may quiet down my hot engine valve chatter. I was though afraid that the flow would be too low. I think I'll disregard the guy saying that 5w-50 killed his crankshaft, and that recommended 20w-50 instead, it doesn't make sense to me.

The cheapest option of "5w-50 Peak Life (Rally Formula)" is $85 per gallon.

 

[Benzadmiral]

Originally Posted By: Teddyen

Here is a few pics, the second is from our constitution day, which we celebrate like nothing else here in Norway. I look slightly crazy with the tilted glasses, but heck.

Darn. Now I want another W126. Yours looks to be in incredible shape! Is that an aftermarket grille, or standard Euro equipment? It looks much better than the grilles I've seen on W126s here. Your car is only a little lighter in color than the battleship gray mine was.

You may have discovered this forum for MB owners: http://www.peachparts.com/shopforum/ They may have some suggestions about curing that tick.

And I wouldn't be surprised if Mercedes Enthusiast Magazine (http://www.mercedesenthusiast.co.uk/) wanted to do a story on your W126 -- especially if you could supply the photos. . . .

 

[Boss302fan]

After years of using 20W50(Castrol) and then 10W40(Mobil 1 HM), I started using Mobil 1 0W40 last summer in my 1990 Jaguar XJS V12... The V12 seems to love it because it runs quieter and smoother then it ever did on the other oils. It was really shocking to me how much better the car ran on the 0W40 oil.

 

[Dogan]

I will follow this topic

I wondered why people use or manufacturer recommends thicker cold oil when there is 0w40

My Engine is old and has oil Leaks oil burning

So Engine burns oil when its cold ??
Because hot number is all same, 40 Weight
And 100C viscosity between 13 - 15
But 40C viscosity has huge difrenece 0w40 and 15w40

 

[Teddyen]

Originally Posted By: Benzadmiral

Darn. Now I want another W126. Yours looks to be in incredible shape! Is that an aftermarket grille, or standard Euro equipment? It looks much better than the grilles I've seen on W126s here. Your car is only a little lighter in color than the battleship gray mine was.

You may have discovered this forum for MB owners: http://www.peachparts.com/shopforum/ They may have some suggestions about curing that tick.

And I wouldn't be surprised if Mercedes Enthusiast Magazine (http://www.mercedesenthusiast.co.uk/) wanted to do a story on your W126 -- especially if you could supply the photos. . . .


Thanks! The grille is just an aftermarket painted plastic insert. I got it in almost the same color as the car, but they also make in a few other variations, including black. The original was dented and damaged, and I quite like the appearance of these aftermarket grilles.

I took about 8 rust spots on the car last year (actually after the pictures was taken), but I see that I have another few spots coming up soon. I've treated the whole underside of the car, including the insides of the doors with lanolin oil at a specialist here in Norway.

It' be fun if the Enthusiast Magazine was interested, maybe I'll give them a call!

Originally Posted By: Dogan
I will follow this topic

I wondered why people use or manufacturer recommends thicker cold oil when there is 0w40

My Engine is old and has oil Leaks oil burning

So Engine burns oil when its cold ??
Because hot number is all same, 40 Weight
And 100C viscosity between 13 - 15
But 40C viscosity has huge difrenece 0w40 and 15w40


Well, to sum up what I've learnt, and correct me if I'm wrong:
Usually, a 0w40 will shear down faster (or more?) than a 15w40, which will give you a somewhat thinner oil at operating temperature that what you started with. Besides, from what I've seen, a 15w40 is usually slightly thicker than a 0w40 at operating temperature from the beginning. For comparing the Mobil Delvac 15w40 to the M1 0w40, the HTHS value is also higher with the 15w40, meaning that the oil behaves thicker when exposed to high pressure and high temperature, such as in the crankshaft bearings and cams.

And, this is just according to my own research, take it with a grain of salt: The oils have gotten better. Today, even oils like 0w40 and 5w40s can maintain proper HTHS values, which they couldn't in the past. That was part of the reason why the factories recommended oils with less VIIs back in the old days.

 

[Red91]

First off, very nice car. I've developed an appreciation for older Mercedes sedans. Second, It would be easier to make suggestions if you were stateside.

If you lived in my climate, the choice would be simple. Quaker State Defy or Pennzoil HM 10W-40. Don't let that sway you though, from reading these suggestions I feel like you have received the best advice from the more knowledgeable members of the forum. Although I'll probably never use it, M1 0W-40 does seem like the optimal choice. I'd probably run the Mobil 10W-40 myself, but that's me.