OK to mix MB ATF 134 & Pentosin ATF 134?
Thread Starter
Newbie
Joined: Jun 2018
Posts: 11
Likes: 0
From: middle GA area
1983 300D; 2016 E350 Wagon
OK to mix MB ATF 134 & Pentosin ATF 134?
I have a 2005 E320 CDI. It currently has MB ATF 134 transmission fluid in it. I am going to change the transmission filter. Is it okay to replace fluid with Pentosin ATF 134 (cheaper) so that the 2 fluids mix?
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Manufacturers always recommend against mixing the same fluids of different brands, what applies also to motor oils, yet owners do it and reports about something going wrong are not coming.
Still it should be concern as it would take chemist to compare chemistry of 2 fluids.
With pan drop you need 4l of ATF. How much money you save? Will it cover potential tow truck fee and repairs?
But regardless, feel free to become Guinea Pig for the rest of us.
Still it should be concern as it would take chemist to compare chemistry of 2 fluids.
With pan drop you need 4l of ATF. How much money you save? Will it cover potential tow truck fee and repairs?
But regardless, feel free to become Guinea Pig for the rest of us.
MBWorld Fanatic!
Joined: Feb 2014
Posts: 6,190
Likes: 1,550
From: MA
2008 E350 4Matic, 2011 E350 4matic
I'm not sure what manufacturers you're talking about. Even Mobil says it's ok to mix different brands of oil, you just don't get the same "superior" protection that you would get with theirs.
Really, this whole question seems to bypass the entire concept of a spec. If the fluid meets spec, you can mix it with another brand that meets the same spec.
This actually happens all the time. People take their cars to various garages and the garage doing the fluid change really has no idea what the previous fluid in there was. They just use a fluid that meets spec and the car continues on as before.
http://www.mobil1.com.hk/academy/faq.aspx
Really, this whole question seems to bypass the entire concept of a spec. If the fluid meets spec, you can mix it with another brand that meets the same spec.
This actually happens all the time. People take their cars to various garages and the garage doing the fluid change really has no idea what the previous fluid in there was. They just use a fluid that meets spec and the car continues on as before.
http://www.mobil1.com.hk/academy/faq.aspx
MBWorld Fanatic!
Joined: Feb 2014
Posts: 6,190
Likes: 1,550
From: MA
2008 E350 4Matic, 2011 E350 4matic
They don't have the same milspec requirements that the military has regarding fluids. If there's a specific spec that is called for in a particular application, it shouldn't matter who makes the fluid. It's why you don't all your eggs in one basket, multiple suppliers in case one has a problem.
And to answer your question, while the taste may differ, they're both alcohols and the mix will get you drunk.
And to answer your question, while the taste may differ, they're both alcohols and the mix will get you drunk.
Trending Topics
Super Member
Joined: Jul 2015
Posts: 795
Likes: 189
From: San Diego, CA
2016 E350 Sport; Mom Wrecked the 2008 E350; sold the 2002 C320
IMHO, it's the same oil, different container and label. Some claim to add more detergents or stabilizers but they all must conform to the same specifications to get approved.
Practically all of the parts on our cars are made by a manufacturer other than Mercedes Benz and sold to Mercedes as well as many other suppliers. Each puts its own brand label on them.
Practically all of the parts on our cars are made by a manufacturer other than Mercedes Benz and sold to Mercedes as well as many other suppliers. Each puts its own brand label on them.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
MBWorld Fanatic!
Joined: Jun 2005
Posts: 1,511
Likes: 267
From: Chicago
2025 AMG E 53; 2018 GLC300 4Matic; 2003 360 Modena
I've mixed OE 134, Shell 134 and Pentosin 134 many many times. No problem. Use BEVO and MB can sometimes lists numerous brands as equivalents. Nowhere does it say you can't interchange them over the service life of the vehicle.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
When I don't have maintenance manual who would give details on ATF, My owner manual clearly says
"Using engine oils of another quality is not permitted and may invalidate the New Vehicle Limited Warranty"
I bet you will find similiar notes on ATF use and guess who will have last word what "different quality" means?
MBWorld Fanatic!
Joined: Feb 2014
Posts: 6,190
Likes: 1,550
From: MA
2008 E350 4Matic, 2011 E350 4matic
Did you ever bother to look for any info on the subject?
When I don't have maintenance manual who would give details on ATF, My owner manual clearly says
"Using engine oils of another quality is not permitted and may invalidate the New Vehicle Limited Warranty"
I bet you will find similiar notes on ATF use and guess who will have last word what "different quality" means?
When I don't have maintenance manual who would give details on ATF, My owner manual clearly says
"Using engine oils of another quality is not permitted and may invalidate the New Vehicle Limited Warranty"
I bet you will find similiar notes on ATF use and guess who will have last word what "different quality" means?
The military uses the same fluids for their vehicles and they require that any fluid that meets spec should be interchangeable with any other manufacturer's fluid that meets spec. That's really the whole point of a spec. You're making a mountain of what is basically a molehill.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Make it 3rd language 
This is your interpretation of "different quality".
Just like sample with Scotch and Bourbon, the same specs can be delivered with different ingredients and you have no way of knowing if some of those ingredients will not interact with each other. Why don't you mix 2 different whiskeys?
If you read diesel section, you will find several reports about relatively new engines seizing becouse dealers put in them "same quality" oils by their own specifications.
I am not saying each such mix has to end in disaster, but who gives warranty it won't?
Again, feel free to try and report back after some time.
This is your interpretation of "different quality".
Just like sample with Scotch and Bourbon, the same specs can be delivered with different ingredients and you have no way of knowing if some of those ingredients will not interact with each other. Why don't you mix 2 different whiskeys?
If you read diesel section, you will find several reports about relatively new engines seizing becouse dealers put in them "same quality" oils by their own specifications.
I am not saying each such mix has to end in disaster, but who gives warranty it won't?
Again, feel free to try and report back after some time.
Last edited by kajtek1; Nov 15, 2019 at 02:22 PM.
Newbie
Joined: Apr 2022
Posts: 2
Likes: 1
e320 wagon 4m
mixing transmission oils
different fluids may mix at certain temperatures and pressures and yet may fall out of solution with each other under different temperatures and pressures. So you may get unexpected changes in performance on especially cold or hot days, or under higher levels of performance. The chemistry is not trivial. If you want to avoid surprises, it is best to use the same oil and stick to that one oil. To flush out a transmission system, I have read it takes 3 flushes. At the end of the day, sticking with the manufacturers suggested oils is your best course.
But if it were me, so long as the oil you are using is on the specific approved oils list for your specific VIN #, I would have no problem adding the pentosin atf 134 to the existing MB oil.
But if it were me, so long as the oil you are using is on the specific approved oils list for your specific VIN #, I would have no problem adding the pentosin atf 134 to the existing MB oil.
