What Kind of Transmission Fluid Do I Need?

Finding out what kind of transmission fluid you need can be a challenge. Take a look at just a few of the dozens of automatic transmission fluid (ATF) specifications on the market:

  • ATF+4
  • ATF DW-1
  • ATF T-IV
  • Toyota* ATF-WS
  • Honda*/Acura* DW-1

You’ve likely heard the term analysis paralysis.

That’s what many people feel when they scan the shelves at the parts store in search of transmission fluid. They just want a quart or two of ATF to top-off their vehicle, but instead they must decipher a series of hieroglyphics or face the specter of their transmission not performing properly.

What kind of transmission fluid do I need?

To answer that question, start in your vehicle owner’s manual. It’ll instruct you to use a transmission fluid that meets a certain performance specification, such as one of those listed above.

The transmission fluid specifications with which you’re likely most familiar are Ford* MERCON and GM* DEXRON. At one time, MERCON- and DEXRON-type ATFs dominated the market and reduced your choices to a manageable few. Today, demand for those fluids has slipped below 50 percent and is declining as original equipment manufacturers (OEMs) continue to introduce their own, proprietary transmission fluid specs.

What is an ATF specification?

It’s a set of performance standards, not an actual fluid. That means you don’t go to NAPA in search of MERCON or DEXRON transmission fluid. You go in search of a fluid that meets the MERCON or DEXRON specification.

In an attempt to make it easy for you, many ATF manufacturers print ATF specs in giant letters on the label. This means the fluid was subjected to – and passed – a series of performance tests stipulated by the authors of that particular ATF specification. However, many people end up confusing the ATF specification on the label for the fluid’s brand name.

Adding to the ATF specification confusion…

Today, it’s normal for most OEMs to author their own performance specifications rather than recommend using a fluid that meets a different OEM’s specification. You can blame it on technological advancements that have made vehicles tougher on transmission fluid than cars of yesteryear. An automaker that introduces its latest 700-hp land rocket wants to be sure you’re using a transmission fluid capable of standing up to the intense heat and stress churning through all those gears.

It may also have something to do with money. Brand XYZ would rather you buy its transmission fluid brand than another company’s fluid, which helps explain why some OEM-branded fluids are so expensive.

So…what kind of transmission fluid do I need?

How can we cut through the confusion and make transmission fluid selection easy? And how do we do it while meeting the performance demands of most modern automatic transmissions?

One transmission fluid to rule them all.

That’s a bit of hyperbole in honor of my favorite trilogy about hobbits and orcs, but it’s not far off.

We formulated AMSOIL Signature Series Synthetic Automatic Transmission Fluid and OE Synthetic Automatic Transmission Fluid to take the guesswork out of ATF selection. Both fluids are recommended for most of the common ATF specs on the market.

  • MERCON V? Check.
  • DEXRON III? Check.
  • ATF+4? We cover that, too.

If you tow, haul or engage in other types of severe service, use Signature Series Synthetic ATF. If you stick to the highway and mostly run to work and home, OE Synthetic ATF is your best bet.

What kind of transmission fluid do I need?

Shop AMSOIL Synthetic ATF

Suitable for use in applications calling for MERCON ULV and DEXRON ULV

AMSOIL Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid suitable for use in applications that call for two of the latest ATF specs in the industry: MERCON ULV and DEXRON ULV. Ford and GM worked together to create these two specs for their 10-speed Ford and GM transmissions available in some 2017 and later Ford Mustangs, Ford F-150s, Chevy* Camaros* and Cadillac* Escalades*, among other vehicles.

The 10-speed automatic transmission continues a trend we’ve seen for several years. Namely, automatic transmissions continue to become more sophisticated to help improve fuel economy. They use more gears that ever before and are often built with lighter materials. In this case, they also use ultra-low-viscosity transmission fluid to help reduce energy lost to fluid friction to maximize fuel economy.

Use the AMSOIL product guide to find the right transmission fluid

We take convenience a step further with our online product guide, which tells you which transmission fluid your vehicle needs. Just enter the year, make, model and engine for immediate results.

Find AMSOIL Products for My Vehicle

So, when it comes time to change your transmission fluid, cut through the confusion by remembering these six letters: AMSOIL.

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.


  1. Hi, I’m looking for a recommendation which fluid to put in my transmission. It’s the M5od-r1hd manual transmission in my 07 Ford Ranger. I used another brand synthetic ATF last time I changed it and it still is difficult to shift into 1st and sometimes into other gears, as well. It doesn’t want to go and sometimes when it goes in, it chatters. Will Amsoil signature series ATF or Amsoil Torque-Drive help this issue? Or do you recommend another one of the Amsoil products? Thanks

    1. Hi Mike,

      We recommend AMSOIL Signature Series Automatic Transmission Fluid in that application. While it provides excellent protection and performance, we can’t make a definitive prediction it’ll fix your chattering problem since all transmissions are different.



    2. I’m also wondering if this is the best fluid to use for my 07 Rangers power steering and transfer case.

      I know there was some confusion years back, about whether or not ATF should be used in Ford transfer cases around the year 2007, because it allegedly would destroy them. And specific transfer case fluid, was recommended by Ford. Does Amsoil ATF meet the requirements of Fords transfer case fluid? Thanks again.

  2. I can’t seem to confirm that Amsoil’s Signature Series Multi-Vehicle Synthetic Automatic Transmission Fluid (ATF) meets the Mazda ATF special spec for the 2006-2015 MX-5 Miata automatic transmission. I can see from the online listing of specs it meets that is appears to be fully compatible, but I’d like rock-solid confirmation.The spec is called (JWS 3309 or Toyota T-IV).


    1. Hi Heman,

      I consulted with our Technical Services Department and here’s what they said:

      Mazda requires using an oil that meets the JWS 3309, also known as Toyota Type T-IV, specification. AMSOIL Signature Series Multi-Vehicle Synthetic Transmission Fluid is a Type T-IV fluid. See its product data bulletin for the specs.



  3. I have a 1979 Fiat 124 Spider 2000 with a GM automatic transmission. The owner’s manual call for DEXRON II ATF. What do you hav to match?

  4. Excellent blog, I thank the author for this useful information. This is important to know that which one is the right transmission fluid. By following your guidelines, now I can choose correct ATF.

  5. Thanks for sharing such a useful information with your video, after reading your blog, I came to know how to choose the correct transmission fluid by following your guidelines.

  6. Been using all products seen 1973. I waited long time for AT oil. Great , last longer and runs cooler. Two thumbs up.

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