DEXRON IIE vs DEXRON III: Finding a DEXRON IIE Replacement

It is supposed to be compatible, that is the most recent word on this topic. Transmission fluids have changed over the years and now the Dexron number may be up to VI. But VI is supposed to harm the seals on an Allison transmission. Finding IIE or III may be difficult.

The replacement for Dexron IIE is Dexron III but Gm has let the patent expire and you should be able to find the III under different brand names. It should also still be available although, it may also have been replaced by upgraded automatic transmission fluid.

To learn more about this topic, just continue to read our article. It has the information you want to know about so you can find the right transmission fluid for your vehicle. Upgrades continue to happen and it pays to stay current with these changes.



First, Dexron is the trade name for a group of technical specifications for automatic transmission fluid. It was created by GM and the company created a trademark for it and later it became the automatic transmission fluid’s brand name.

GM used to license the name and specs to other companies that sold the same fluid under their brand names. Second, this is a semi-synthetic transmission fluid that enjoyed a universal application.

It was also the middle of the Dexron II product line as it followed II and came before IID, It seems that only Shell and Mobil bought licensing rights from GM as they are the only companies listed on one of the compatibility charts for this level of automatic transmission fluid.

That changed when GM developed DexronIII, which came out in 1994. It may not be possible to find any Dexron IIE anymore and the only reason it comes up in conversations is that there are still people who like owning older cars.

Their manuals call Dexron IIE and when these owners go searching for it, they find that it is very difficult, if not impossible to find this automatic transmission fluid. They have to decide if they want to use III, or VI as a replacement.

What Replaces DEXRON IIE?

Dexron III is the replacement for this fluid. In fact, it is one of the transmission fluids that you will see in all auto parts stores. It has a universal application as the fluid is made to the same standards by all brands marketing it.

If you look at the label these days, you may find Dexron III is marketed as Dex/Merc, the latter standing for Mercon, that is because these two transmission fluids are interchangeable.

They are made to almost the same specifications and the manufacturers decided to market them together because of these traits. However, Dexron III was the primary automatic transmission fluid for about 12 years. It lasted from 1994 to 2006 when Dexron VI took over.

You should be able to find Dexron III in the auto parts stores because there are a lot of cars on the road today that use that transmission fluid. But we are sure that VI is backward compatible and should work just as well.

DEXRON IIE Transmission Fluid Equivalent


As you just read, Dexron III was the upgrade to this transmission fluid. That was so until Dexron VI was made. The VI is the upgrade to III and should be used when Dexron IIE is called for.

Many people are very satisfied with the performance of VI and recommend it to other owners of older vehicles. It is doubtful that you can find Dexron IIE anymore as it has been out of production for about 30 years.

VI came on the market in 2006 and has been used in most cars since that date. But if you want to stick to tradition, you should be able to find Dexron III still being sold under different brand names.

There are also synthetic transmission fluids that are compatible with Dexron III. They would be okay to use in a transmission calling for Dexron IIE. Some of the brand names are TES-295, Pennzoil Platinum High Mileage ATF, Valvoline or Castrol Dex/Merc, and more.

You should not have a problem finding a good compatible transmission fluid that will replace Dexron IIE.


It seems that the biggest difference between Dexron II and Dexron III is the fact that GM used Jojoba oil and other natural ingredients in the former product. But those inferior ingredients tended to cause transmission issues so the company stopped using them.

That is when Dexron IIE was produced as it had to compensate for those problems the earlier inferior ingredients caused. Since Dexron IIE has gone out of production over 25 years ago, this is not a fair comparison.

Dexron III is the backward compatible upgrade to Dexron IIE and it was put in all transmissions between 1994 and 2006. The real comparison should be between Dex5on III and VI as both transmission fluids are still on the market and IIIH may be as close to Vi as you can get without buying VI.

Since there is no real difference between Dexron III and Mercon V, there is nothing to compare there either. If you own a very old car, then you should not have any trouble using Dexron VI as it also is a backward compatible transmission fluid.

Is DEXRON III Compatible With DEXRON II?


The answer to that is as you already know. Yes, it is and it was the upgraded version of II after IIE and IID were produced. In keeping up with the upgrades in transmissions, GM had to upgrade its transmission fluid.

This was done in 1994 as we have already stated. The process is called backward compatible as the fluid had to be able to work with those transmissions that used Dexron II.

If you still have an older manual for those pre-1994 vehicles, you may see inside that the company called for Dexron II or IIE, or IID. That has confused many owners of these vehicles as no one can find II or its subsequent variations anywhere.

III is going the way of II as GM has upgraded its automatic transmission fluid to VI and that fluid has been in cars since 2006. This newer option is also backward compatible and it should work fine in most transmissions.

Or you can just switch brands and go with Mercon V as that is compatible with Dexron II & III.


There really is not much difference between these two fluid types. The IIIH is the final upgrade in the Dexron III series. What is special about this option is that it was given powerful additives to stop oil degradation.

Plus the oil used was highly refined and all of these changes were to extend the life of the fluid as well as the transmission components. IIIH had very tough specs that could only be matched by synthetic versions of transmission fluid or those fluids made from better base oil.

Overall, it is just an upgrade that improved on an already improved formula and should have helped give your transmission a longer lifetime. Other upgrades included a better oxidation-resistant formula and a better as well as updated friction modifier.

While both transmission fluids were good, it was just that IIIH was better. But that is what happens as technology helps improve different products.

Is It OK To Use DEXRON VI Instead Of III?


Technically, it should be okay to use Dexron VI instead of III. There are some differences between the two and Vi is thinner than III which causes some owners some concern.

Also, the viscosity levels are different with III once again being higher than VI. It is said that Dexron VI is a fully synthetic transmission fluid but some people disagree with that assessment.

Then VI has improved friction stability and improved oxidation stability which make sit a superior product to III. There is a catch though and it is something you should be aware of.

You are not to mix the two fluids as they are not made to work with each other. If you are going to ad transmission fluid make sure you add the type that is already in your transmission.

Then VI has a longer shelf-life than III and that keeps the transmission fluid in better shape. It also makes VI a more economical option over III.

Some Final Words

Things change. Not only do transmissions change and are upgraded so is transmission fluid. While you can still get Dexron III you won’t be able to buy any version of Dexron II unless some off-brand is still producing it.

While there are some backward compatibility traits, do not mix the transmission fluids. Stick with one over the other for a longer-lasting transmission.

Right now VI is the standard transmission fluid and has been for almost 20 years. You may want to upgrade from IIE and III and use VI from now on.

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