2017 GLS550 135k Service

It's your engine, transmission, driveline
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

Somewhat interesting that if I was the first to somewhat document my experience with it I would at least be able to show Valvoline our full discussion history and trepidation, including reasonable viscosity and other concerns in my write up to them if I have to ask them to cover the cost of a transmission overhaul.
kevm14
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Re: 2017 GLS550 135k Service

Post by kevm14 »

Yeah if you want to get involved with all that. But this would cross way behind you just trying to more conveniently maintain your vehicles. I did think of that though.
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

Figured I'd write Valvoline a question since we've been debating this so heavily:

"I'm considering what transmission fluid to use to service my 2017 Mercedes Benz GLS 550 with a 725.035 transmission during a 135k mile service. Valvoline Maxlife multi-vehicle shows Valvoline's recommendation of use for applications that call for Mercedes Benz fluid 236.17 which my transmission requires, but it also lists a number of 236.XX fluids that are of different viscosities and according to MB incompatible with each other. Can you provide any additional MB specific info or identify what comparisons/analysis Valvoline did to verify applicability to MB 722.9 transmissions/ 236.17 applications? "

We'll see what answer I get.

Just realized the last line should've said 725.035 instead of 722.9. Oh well.
kevm14
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Joined: Wed Oct 23, 2013 10:28 pm

Re: 2017 GLS550 135k Service

Post by kevm14 »

I am definitely interested in an engineering response. I am NOT interested in a marketing response.

Again, on the spec debate, another thought is, if Honda and the other applications (like ATF+4, DEXRON VI and MERCON V) are less happy with Maxlife, does that mean the other transmissions are fine with it? Or does it mean that they are also working suboptimally but just not presenting in an obvious way? For a strawman, if would be like comparing transmission performance with water contamination. Transmission A may shift better with 2% water than transmission B with 2% water. This is NOT proof that the water is "not effecting" transmission A, or that the fluid with 2% water contamination is "just as good" as with uncontaminated fluid.

Going into this debate, I generally had the opinion that do-it-all transmission fluids were totally outdated and frankly impossible (not surprisingly I also don't believe in add-to-any coolant formulations for modern cars - this might matter even more than transmission fluid!). The last one I really remember was DEX/MERC which was DEXRON III and MERCON. I'm not entirely sure I have even used that in an actual transmission, probably more for components that called for ATF and that was good enough. However, it is possible that Maxlife is using a high quality synthetic base stock as a starting point, which is probably more than can be said for many of the applications listed on the bottle. In those, Maxlife may well be a genuine improvement. But I don't think this applies universally. I think that's the issue. And I think all automotive systems are much MORE picky than they have ever been, based on the level of performance and efficiency they have been tasked with.

On the liability thing, there are many, MANY things sold on the shelf at auto parts stores that if you pour them into your engine or transmission, you may well damage them. Yet these products are available. Why? It goes back to the point I made before. You deviate from spec when there is an issue and perhaps your only official remedy is VERY expensive. But you don't pour Motor Honey into a perfectly good engine. Additives are a slightly different topic than running pure Maxlife, but it's a deviation from OEM spec nonetheless. Actually, that brings up a better point. If you wanted best results with a product like Maxlife, you should do a 100% fluid change. Putting substantial miles on a 50% Maxlife/50% OEM fluid blend is probably even worse than 100% Maxlife. I should have thought of this before. This is another jump away from the original cost/convenience argument.
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

Here's a data point that probably supports your arguments for Benz-approved only and "universal" not applying.

Royal Purple universal fluid is apparently "not" recommended for 725.03X applications:
https://royalpurple.lubricantadvisor.co ... ion/130685
kevm14
Posts: 15528
Joined: Wed Oct 23, 2013 10:28 pm

Re: 2017 GLS550 135k Service

Post by kevm14 »

Yes though their ATF says "Mercedes Benz 236.12, 236.14, 236.15, 236.41"

And ZF.

Viscosity @ 40°C, cSt ASTM D445 29.3

That's thick/normal. 236.15 and 236.17 are considerably thinner. What was it, like 18? 17.5?
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

Valvoline responded with a typical marketing response quoting the product advertising sheet only.
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

Wound up ordering this for stock plug-in and hopefully corrosion resistant trailer receptacle wiring. The rectangular plug mated with the stock Benz wiring harness, so it should all be factory type and weather resistant connections.

https://www.etrailer.com/Custom_Fit_Veh ... 11933.html
rpaoness
Posts: 283
Joined: Tue Jan 27, 2015 5:47 pm

Re: 2017 GLS550 135k Service

Post by rpaoness »

I noticed relatively minor oil leaking from the upper cam gear timing covers. From precursory inspection it looked like the passenger side is a little worse than the drivers side. Need to read up on what's expected to be in the way and if it's just sealant or if there are any gaskets I should order up.
kevm14
Posts: 15528
Joined: Wed Oct 23, 2013 10:28 pm

Re: 2017 GLS550 135k Service

Post by kevm14 »

That's a common leak. It's just sealant. The passenger side is easier. Probably have to remove the boost pipes which can get stuck down at the turbos. Driver's side will probably require removal of the oil filter adapter and maybe oil cooler. It would make sense to do new seals on ANYTHING you disturb (particularly if you have to separate any oil cooler stuff). I guess I can dig up the instructions so you can get a better idea what you want to plan for.

Watch out for all turbo coolant lines which can be brittle though yours may be newer.
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