OEM vs aftermarket ATF

[Rand]

Depends on the transmission.
I would only use subaru CVT fluid in their CVTs (5 different fluids now)

not something that claims to be 40 specs for 400 different transmissions.

Now an older conventional transmission that called for dex VI, dex III, or mercon V.

I would consider an appropriate aftermarket fluid.. but would be tempted to buy something that does not have 200 specs on the bottle.
such as supertech mercon V etc.

Or supertech LV for dex VI etc.

Also wouldnt feel bad about using redline, amsoil, etc in a conventional transmission.

 

[JavierH19]

I only used ac delco brand atf once because I got it for free from a friend who didn't need it anymore. Other than that i've done over 600k on the original internal 4 speeds in my 03 and 05 on non oem fluid and yup the yukon is heading to 350k unrebuilt and still not blown up as with the near 290k sierra. You can use maxlife or if you want a longer interval the EP.

 

[Blang]

So in your opinion something that is "recommended for Dexron" but not "Dexron approved," like MaxLife or Extended Protection, should be avoided?

Yeah, the absolute numbers are. But I guess I just don't know enough to know how much different transmissions care about viscosity. As someone else mentioned, the fluid is such a huge component of transmitting power and operation, how can different ATFs with a wide range of viscosity all claim to be applicable. Even the Dexron Approved Valvoline has a different viscosity than Dexron itself.

Makes sense, more thermally stable. Regarding ACDelco, I have read online that it's full synthetic, others say synthetic blend. I saw one bottle that stated "fully synthetic blend." No idea what to make of that.

I'm aware. But even given that, you can send fluids made by the same manufacturer, under different labels but same spec, to a lab, and they'll come back with different properties.

Yeah, and that additive package is proprietary so no clue without analysis. And the Motor Oil Geek said that transmissions are certified to OEM fluids, so to stick with OEM. And I think he said/suggested Approved is good enough, but recommended might be pushing it.

There are definitely some specs of Max Life where the viscosity varies considerably from some of the original specs of certain certs (Mercon perhaps?), but with Dexron VI in mind I use it with confidence.

ACDelco.... I've seen ACDelco ATF that is Full Synthetic and some that say nothing about base stock. Valvoline seems to have the best line of readily available ATFs for reasonable prices and I don't think I've used anything besides Valvoline products in my transmissions for that reason. Engine oil is a different story. As far as the shudder goes... if it were mine I would use the Max Life or other full synthetic fluid and likely a small bottle of Lubegard.

 

[Johnny248]

I've used Maxlife in several ZF Chrysler Transmissions without issue. Some have even said it shifts better.

 

[martinq]

Every bit this!! ^^^^ including Lubegard Shudder fix additive

Never add anything to a gear, hydraulic or transmission fluid unless it is recommended or required by the mfg of the equipment or fluid. Trying to be a chemist is not going to work out for the better, at best you will do no harm.

 

[martinq]

Depends on the transmission.
I would only use subaru CVT fluid in their CVTs (5 different fluids now)

not something that claims to be 40 specs for 400 different transmissions.

Now an older conventional transmission that called for dex VI, dex III, or mercon V.

I would consider an appropriate aftermarket fluid.. but would be tempted to buy something that does not have 200 specs on the bottle.
such as supertech mercon V etc.

Or supertech LV for dex VI etc.

Also wouldnt feel bad about using redline, amsoil, etc in a conventional transmission.

If you want to feed the OEM / Subaru money making machine then that's fine but the transmission will not care what part # or % markup your fluid has. Subaru CVTs are covered by aftermarket fluids and multi-ATFs just like everything else and it's not a problem.

Get your transmission clean, keep it clean and don't let the fluid overheat. These are critical, the fluid is not.

 

[martinq]

Is that anything besides your opinion?
If one fluid fits all why does subaru stock 6 different ones.
including 4 separate cvt fluids?

If I go oem its the right color for the warranty too.

If you service, repair or rebuild equipment and understanding the basics of lubrication requirements then it makes intuitive sense. You could also scan the horizon for all the class-action lawsuits that Valvoline, Castrol, Amsoil (and countless others) will be receiving... any day now... since the last 20 years?

The Subaru CVTs are not special enough to require a unique CVT fluid. Subaru (and every other mfg) need to harvest their customers as effectively as possible.

Pick your SKU, part #, pretty packaging and feel good about the excessive markup you pay. That's what it's there for. You're doing the right thing.

 

[Elkins45]

My experience with automatic transmissions is extremely limited but I bowed to pressure and bought genuine Toyota WS for my first automatic Scion. For my second I used Idemitsu, which sources said was the same stuff just in the actual manufacturers bottle. For my RAV I went back to WS, mostly because I paid 3X for the RAV. Ask me again in 3-4 years if it made a difference.

 

[skaughtz]

Never add anything to a gear, hydraulic or transmission fluid unless it is recommended or required by the mfg of the equipment or fluid. Trying to be a chemist is not going to work out for the better, at best you will do no harm.

Wait. Which is it? OEM vs Aftermarket fluid is irrelevant or additives impact performance? Because spec sheets show clearly that different ATF have different additive packages.

 

[GSCJR]

My 2012 Legacy has had red fluid in its used CVT, for the last five years; probably the cheapest universal CVT fluid available at the time.

 

[FDT09]

Never add anything to a gear, hydraulic or transmission fluid unless it is recommended or required by the mfg of the equipment or fluid. Trying to be a chemist is not going to work out for the better, at best you will do no harm.

Yeah, I'm always skeptical about adding additives without clear data. I'm not a chemist, and I don't know how different additives can interact with each other. I know in the case of motor oils, sometimes oil additives can interfere with the oil's additive package. I'm sure it's similar for ATF. But in other cases it can work with or improve on the additives too. I'm sure Lube Guard works, but if I don't know what exactly it's doing inside, I'm hesitant to add it.

 

[martinq]

Wait. Which is it? OEM vs Aftermarket fluid is irrelevant or additives impact performance? Because spec sheets show clearly that different ATF have different additive packages.

Sure the ad packs are different, there are different MFGs of those additives, and different options available. Choose your flavor, pick of the week. But what is inside the transmission? What is inside your transmission? Does it have pumps, gears, solenoids, valves, clutches, pistons, chains, bearings? How are your special bearings different from other special bearings? Are the clutches in your transmission revolutionary?

The fluids offered by quality mfg like Valvoline, Castrol, Amsoil, Pennzoil, etc, are actually trustworthy and can be safely used as recommended. We've known this for decades and it's been backed up by first hand experience ad infinitum, for decades... not just in 2024, 2025, 2026.

The OEMs will CONTINUOUSLY release new formulas, specs, requirements into the market which the aftermarket suppliers will adapt to. So for the first year or two you MAY have no realistic option but to pay the $75/qt for the precious OEM fluid but in the third or four year you can get an aftermarket fluid which EXCEEDS the OEM for $25/qt or maybe even $6/qt.

Engines are no different, they have operational requirements and yet every year we hear about how the OEM has failed their customers with defective engines and transmissions. These faults have NOTHING to do with the aftermarket fluid MFGs who are providing fluids that EXCEED the OEM requirements and at a better value. Astonishing.

As an intelligent, experienced tech who appreciates quality, performance and value, I have little interest in feeding the OEM their 200 or 400% markup when I can get superior performance AND a better value delivered directly to me. If I could acquire equivalent performance for the same cost as the aftermarket would I even bother? I don't desire the automotive MFGs logo on the bottles, I can get the real goods directly from the fluid MFG for much less.

 

[martinq]

Yeah, I'm always skeptical about adding additives without clear data. I'm not a chemist, and I don't know how different additives can interact with each other. I know in the case of motor oils, sometimes oil additives can interfere with the oil's additive package. I'm sure it's similar for ATF. But in other cases it can work with or improve on the additives too. I'm sure Lube Guard works, but if I don't know what exactly it's doing inside, I'm hesitant to add it.

The automotive MFG should tell you the requirements for your powertrain fluids. If you want to add something to those fluids then check with the MFG (automotive or fluid). A friction additive is required for certain limited slip differentials but you don't hear about that often anymore.

Anytime I've see someone adding to their powertrain fluids it's almost always out of ignorance and / or marketing. Someone is getting paid for that behaviour and it's certainly not you (unless you're the salesman / distributor).

 

[4wd]

I've used Maxlife in several ZF Chrysler Transmissions without issue. Some have even said it shifts better.

If I ever did a full fluid exchange - would do that.
But, at just 5L per spill/fill … doing the Zeus juice …

 

[Volvo_Expert_Tech]

After working at a Volvo dealership for 17 years, every single one of our ATF flushes were used with the BG universal fluid with ZERO issues. In fact, I fixed many transmission shifting issues with a BG flush. NOTE: obviously these two fluids arent for CVT or ZF, but you're crazy to own a CVT if you do.

Valvoline MaxLife universal is just like the BG universal and I see no issue in using it. For my 2024 Audi S5, I will be using Ravenol 8HP only because its identical to the ZF and cheaper here in Germany.

 

[4wd]

After working at a Volvo dealership for 17 years, every single one of our ATF flushes were used with the BG universal fluid with ZERO issues. In fact, I fixed many transmission shifting issues with a BG flush. NOTE: obviously these two fluids arent for CVT or ZF, but you're crazy to own a CVT if you do.

Valvoline MaxLife universal is just like the BG universal and I see no issue in using it. For my 2024 Audi S5, I will be using Ravenol 8HP only because its identical to the ZF and cheaper here in Germany.

My dealership is telling me that cleans the filter. How?

 

[Volvo_Expert_Tech]

My dealership is telling me that cleans the filter. How?
By reversing flow and then flushing more?

I am not buying that. It does not reverse flow, its not possible as it uses the internal transmission pump to flow the fluid.

It will clean the entire system by flushing 16qts through a average 7-8qt system, but not the filter nor the magnet at the bottom of most pans. Most machines have a window where you can watch the fluid go from black to ruby red as its flushing through the vehicle.

Volvo didn't have serviceable filters and listed ATF as "lifetime" fluid which we all know is BS.

 

[4wd]

I am not buying that. It does not reverse flow, its not possible as it uses the internal transmission pump to flow the fluid.

It will clean the entire system by flushing 16qts through a average 7-8qt system, but not the filter nor the magnet at the bottom of most pans. Most machines have a window where you can watch the fluid go from black to ruby red as its flushing through the vehicle.

Volvo didn't have serviceable filters and listed ATF as "lifetime" fluid which we all know is BS.

They literally don’t offer any other service - and now have made it ridiculous to remove the pan (Tahoe) without removing part of the exhaust. Same with our Lexus.
I can change 5 quarts in our older Tahoe in 5 minutes …

 

[Volvo_Expert_Tech]

They literally don’t offer any other service - and now have made it ridiculous to remove the pan (Tahoe) without removing part of the exhaust. Same with our Lexus.
I can change 5 quarts in our older Tahoe in 5 minutes …

I shared a shop with the Cadillac techs at my old dealership so I know exactly what you are talking about. The guy next to me was the designated transmission rebuilder. That was all he did. I did not envy his job.

The transmission flush machine taps into the line from transmission to cooler/radiator. It nearly universal on all vehicles and i do recommend having it done around 50k. I will be doing a drain/fill on my transmission at 40k because I am OCD.

 

[4wd]

I shared a shop with the Cadillac techs at my old dealership so I know exactly what you are talking about. The guy next to me was the designated transmission rebuilder. That was all he did. I did not envy his job.

The transmission flush machine taps into the line from transmission to cooler/radiator. It nearly universal on all vehicles and i do recommend having it done around 50k. I will be doing a drain/fill on my transmission at 40k because I am OCD.

Okay - this will be the first time I didn’t do it myself - but it’s also the first time to have a dealership extended warranty and service plan. Guess it’s this at 45K per them:

https://www.bgprod.com/bg-master/uploads/PF19-002_manual.pdf