Transynd vs. Dex VI

[ledslinger]

There have been several discussions about the quality/durability of Transynd vs. Dex VI. It has been claimed that Transynd doesn't meet Dex III H specs, and that if you read an SAE paper on trans fluids it would be clear that Dex VI is a better fluid.

I haven't read this paper but I wish to make some observations based on reading posts on other forums by the engineer that developed TES 295 fluids, and reading discussions on GM transfer case fluids at Diesel Place forum.

According to "Mr Transynd" who wrote the specs for TES 295, Transynd was developed to address some deficiencies in TES 389 fluids, which he says are all Dex III H fluids. He says they are good fluids but they lose viscosity and he developed TES 295 as a replacement offering longer drain intervals. Looking at drain intervals for TES 389 and TES 295 fluids on Allison's site shows the confidence they have that Transynd is more durable than Dex III H.

If he developed an improved and more durable fluid than TES 389, which meets Dex III H, it would be a real oddity if the improved and more expensive fluid didn't even meet the performance of the original fluid.

A performance deficiency is implied with regards to use of Dex VI in GM transfer cases. Although owner's manuals spec Dex IV in GM trucks a bulletin has changed the fluid requirement to GM Manual Transmission Fluid, which has been admitted to be Dex III, and I think VOA's indicate this also. We have an application in which Dex VI apparently wasn't durable, so Dex III was relabeled and required.

Another point is that Allison, which is no longer owned by GM recommends Transynd for extreme cold applications, over Dex IV that is factory fill.

 

[ledslinger]

Read all Dex IV's above as Dex VI. For some reason I'm not offered an edit option right now.

 

[SteveSRT8]

In transfer cases. That's the key.

Note that we have an 09 Z71 Duramax 2500 HD with the Allison trans and it has been happy on the Dex VI.

But I would never be comfortable putting that stuff or any other auto trans fluid in a transfer case!

 

[dnewton3]

Originally Posted By: ledslinger
There have been several discussions about the quality/durability of Transynd vs. Dex VI. It has been claimed that Transynd doesn't meet Dex III H specs, and that if you read an SAE paper on trans fluids it would be clear that Dex VI is a better fluid.

I haven't read this paper but I wish to make some observations based on reading posts on other forums by the engineer that developed TES 295 fluids, and reading discussions on GM transfer case fluids at Diesel Place forum.

According to "Mr Transynd" who wrote the specs for TES 295, Transynd was developed to address some deficiencies in TES 389 fluids, which he says are all Dex III H fluids. He says they are good fluids but they lose viscosity and he developed TES 295 as a replacement offering longer drain intervals. Looking at drain intervals for TES 389 and TES 295 fluids on Allison's site shows the confidence they have that Transynd is more durable than Dex III H.

If he developed an improved and more durable fluid than TES 389, which meets Dex III H, it would be a real oddity if the improved and more expensive fluid didn't even meet the performance of the original fluid.

A performance deficiency is implied with regards to use of Dex VI in GM transfer cases. Although owner's manuals spec Dex IV in GM trucks a bulletin has changed the fluid requirement to GM Manual Transmission Fluid, which has been admitted to be Dex III, and I think VOA's indicate this also. We have an application in which Dex VI apparently wasn't durable, so Dex III was relabeled and required.

Another point is that Allison, which is no longer owned by GM recommends Transynd for extreme cold applications, over Dex IV that is factory fill.




I find a few things incorrect in your statements, but I'll give you the benefit of the doubt in that you may just be repeating what you've read, and not really put much detailed analysis into it.

Transynd is a TES-295 licensed fluid; "Transynd" is NOT a specification - it's a brand name. There are many other brands that are also TES-295 licensed. That TES-295 fluid spec existed LONG before TES-389 was initiated. To claim that Transynd was developed to deal with TES-389 issues is getting the cart before the horse.

TES-295 is the very grueling, ultra-high standard set by Allison for hydraulic fluids (ATFs) that would be otherwise known as DEXIII/Mercon fluids. I don't know of any fluid that could pass if it were not PAO baseed. No convantional oil would hold up, so TES-295 licensed fluids are all high end PAOs to the best of my knowledge.

When GM owned Allison, the DEXIII existed as the "normal" fluid and the TES-295 fluids were what Allison used. When GM started manufacturing their own 1000 trannies (Baltimore) in addition to Allison (Indy), they used the Baltimore trannies in the 2500/3500 trucks, and the Indy trannies went into other applications.

Along in 2006, GM stopped licensing DEX III (as did Ford with Mercon). GM developed DEX VI and it is generally the only ATF they offer since 2006. During that time, GM still owned Allison, so GM essentially forced Allison to recognize DEX VI in their documentation; they did. However, Allison treated DEX VI as they did all other "non-TES-295" fluids.

Yes, DEX VI has much better vis retention and much better oxidation resistance than the former DEX III, but it couldn't meet the TES-295 specs for a few reasons (vis, etc). So, Allison simply had "TES-295" and "non-TES-295" fluids. But, they discovered that the DEX VI was not compatible with the seals in the Allison trannies due to part of the DEX VI chemistry package. (There is a known serial number cut off for both the Indy and Baltimore plant products. After those cutoffs, DEX VI is acceptable for the trannies). However, with DEX III gone, Allison basically had to recognize DEX VI as an alternative to the ultra-expensive TES-295 licensed products.

Then, GM sold Allison. And the gloves came off. A few things happened.

GM sold Allison, but kept the name and manufacturing rights to the 1000 series tranny, so that they could continue to market their 2500/3500 trucks with the trannies made in Baltimore. The Indy facility still makes the Allison 1000, their parent company. The trannies are bound for different applications. But by keeping the rights, GM uses the "Allison" name and puts DEX VI in it. "Allison" trannies from Indy leave with TES-295 in them.

Allison promptly dropped the DEX VI as an approved fluid when GM sold them. They created the "new" TES-389 specification. That "new" spec was simply to recognize and license fluids that would have met the "former" DEX III conventional oil specs, with the added assurance of seal compatibility. DEX VI cannot pass that muster, because the min vis of (former) DEX III type products is 7.3 and the max is 6.0 for DEX VI (hoping my numbers are correct here; correct me if not). No fluid can be above one and below the other at the same temp at the same time!

GM has bulletins stating that DEX VI is backwards compatible in all trannies (but the reality is that it's a risk in the Allisons before the cutoff). It is also not good for manual trannies and transfer cases that were originally spec'd for DEX III fluids, , by GM's own statements.

Any manual transmission or transfer case that was designed for DEXIII/Mercon type fluids should still use those. Any fluid meeting TES-389 would be a good choice, and I would also trust the "unlicensed" fluids from other quality brand names that would be "DEX/Merc" or "D3/M" or such. No - there is no more licenses for those products. But, I still have faith that they are reasonably constructed and made. And again, if you don't like the risk, you can get a TES-389 fluid that is the same as the former DEX III; Allison literally made that spec to duplicate the former GM spec, with a few minor tweaks.

Also, GM offers a "Manual Transmission and Transfer Case Fluid” (part #88861800 in the US and #88861801 in Canada) that is (by GM Tech-link documents) simply the former DEX III fluid renamed, with a new part number. It is essentially the DEX III in a newly marketed product. It is NOT good for ALL manual box applications; it is only good for those applications that used the former DEX III. When GM dropped the DEX III license, they needed a "new" fluid that would fill those applications that DEX VI could not fill. Their answer was to rename DEX III into the product I stated.

Any TES-295 fluid (or clone, for that matter) would do fine in any Allison 1000 tranny, and any NV261/263 t-case, and a host of Ford applications that would have been serviced by Mercon. Yes, if you're under warranty you must consider the ramifications of using a fluid that isn't "approved", but that's true of any lube choice.

This was a game of corporate political one-upmanship. GM dropped DEX III, strong-armed Allison into recognizing DEX VI, then sold part of Allison, and now two identical versions of the Allison 1000 are produced. Depending upon who sold you the vehicle is going to sway the version of which fluid you should be using.

When it comes to the t-cases, the same can be said. I spoke with the product design engineer directly on the phone a few years ago about the NV261/263 cases. Those were designed for DEXIII/Merc type products. Any TES-295, TES-389, GM #88861800, "DEX/Merc" or "D3/M" fluid that comes from a good company will suffice quite well. As always, you’ll get longer service life from a synthetic version of DexIII/Merc. There are clones of the TES-295 fluids such as Amsoil’s ATD, Schaeffer’s 204S-AT, and DA-Lubricant’s AutoTrans-5. Also, the Amsoil “ATF” and Mobil 1 ATF would work well in those applications.

That help clear up the mud in the water?

 

[ledslinger]

Thanks for the detailed explanation, I was using "Transynd" as a blanket reference to TES 295 fluids since it is the most common. I didn't know the TES 295 spec was before the TES 389. I assumed it came after since the guy that developed the TES 295 fluid said it was in response to viscosity breakdown of TES 389 fluids. I suppose he meant Dex III H fluids, that would later become TES 389.

As far as clearing up the mud in the water, no. The question still remains about the relative performance/durability of TES 295 fluid vs. Dex VI. There have been discussions here that TES 295 doesn't meet Dex III H specs and that an SAE paper on trans fluids (available for sale) indicates it either sucks or is outperformed by Dex VI.

Interesting that TES 295 fluids must be PAO since Shell calls its version a blend:http://www.greatlakesoil.com/products/2363-data.pdf

Here it says Shell Donax TX is made with SHELL XHVI synthetic base fluid:http://www.epc.shell.com/Docs/GPCDOC_GTDS_Donax_TX_(G-34077).pdf

 

[dnewton3]

I cannot believe that there any SAE paper can prove that TES-295 "sucks". And I think that companies like Mobil, Shell, Amsoil, Schaeffers and others would disagree as well. The licensed and cloned products are often the top offering in their respective product lines. Feel free to quote the SAE paper document number; I'd be very interested to buy and read that document. At a bare minimum, provide the link to the thread post here on BITOG that makes that assertion, please. Further, which "guy" are you referring to? I'd like to have a conversation with him!

As for a TES-295 fluid being inferior to DEX VI, I'd have to question that as well. We must understand that there are some applications where they are interchangeable, and some where they are not. So it depends upon the use. In some cases, DEX VI is going to be a much better choice because of it's thinner vis. In other app's, I'd take a TES-295 over the DEX VI every time. As with all lube topics, you cannot pick a clear winner because there are too many useage variables to say one is flat out "best" for every situation. It's no different than engine oils; there are "better" choices for given situations, but there is no "best" oil.

DEX VI is a great fluid; excellent vis retention and oxidation resistance. But isn't that also the battle cry of PAOs? Why would a TES-295 fluid be inferior to DEX VI?

Here's a little known fact. In the "new" GM Allison trannies in the trucks, the DEX VI is standard fill. And those trucks have a "high idle" feature for cold temps where the engine is used against the tranny torque converter to warm up both in a quicker fassion. But GM discovered that the DEX VI does not react well to that operation in uber cold temps (well below zero F), and actually recommends TES-295 fluids for those extreme cold environments.

Also, in Allison testing, DEX VI was never certified for use past the "non-TES-295" OCI limits. That doesn't mean it's inferior, but it surely cannot prove that it's as good as TES-295 in severe duty use. The TES-295 fluids are certified for extended OCI even under severe use. And Allison has a very good, defined meaning of severe. They are talking about the type of use where low speeds and high torque loads are flashing the torque converter all day long. Use such as refuse trucks, shuttle busses, etc. Only TES-295 fluids are certified for extended OCIs in that regard, and DEX VI never was. Maybe DEX VI was never tested to that standard, so perhaps it could have passed muster, but as of this point, there is no proof that DEX VI is superior to TES-295. My point is that the absence of DEX VI as an approved TES-295 fluid may have been due to the fact that it was never tested, or it may have been tested and not passed. But we can be CERTAIN that it never approved for TES-295 certification. For all we know, it may have failed only because it has (on purpose) a vis that was too low for TES-295 certification. I don't know because I'm not privy to that testing protocol. All I know is that only the highest end products in each brand, costing the most money, pass that licensing standard. Even non-licensed products (ATD vs. ATF in Amsoil's line) cost more for the "cloned" fluid. Since Amsoil has no license to pay for, why would ATD cost more? It's only logical to believe that ATD has some base stock and additive package that is superior to even their ATF product. Bottom line: TES-295 standards are very demanding, and only the highest performing products pass the finish line.

I would say that DEX VI is a giant leap ahead of DEX IIIh fluids, but there is no reasonable proof I've seen that it's superior to TES-295 products.

Further, I'm not stating that only PAOs can be licensed; I'm just not aware of any non-PAO products that fill that spec. I put very little faith in marketing descriptions of fluids these days. Regardless, if Shell has a product that is TES-295 licensed, then it's a very stout fluid, no matter if it uses Jell-O as it's base stock. BTW - I don't see Shell having a licensed TES-295 product, so I don't know what product you're referring to, but it's not on this official Allison page:
http://www.allisontransmission.com/service/autoapp/172/viewpage.jsp?ThisPage=3.
Which is why I say marketing words mean little to me. "Suitable for use" is one thing, and an approved license is completely different. That is a whole othe topic; that of licenses versus marketing intent.


I'm not saying you're wrong, but I see no evidence that DEX VI is the "best" over TES-295 fluids, and knowledge of the testing standards and conditions suggest that logic direct us to other conclusions.

Some people and companies fear thinner fluids, and perhaps that's why Allison didn't like DEX VI. I don't fear thin fluids; I'm known for using OEM spec'd think fluids. But for some reason, Allison never licensed DEX VI to TES-285 standards. That's all we can know.

The only way to know FOR SURE is to use both fluids in the same exact situation, and then do UOAs and equipment tear-down analysis for performance validation. And Allison has already done that for me to a degree and level much deeper than my pocketbook could ever fund.

AS for TES-295 not passing (former) DEX IIIh spec's, that seems specious to me. Any moderate dino fluid could pass DEX III; only top end PAOs have been TES-295 licensed. Just what part of the spec would a TES-295 have failed in former DEX III licensing by GM? TES-295 fluids were designed for top tier performance in DEX III applications. Your comments seem counter intuitive to me. (This would be akin to suggesting that Mobil 1 engine oil is not approved for use in their Mobil Clean 5000 applications. To me, it just doesn't make sense). Now, what might be true is that companies marketing fluids in both TES-295 and (former) DEX III applications, never submitted their TES-295 products for DEX III license approval, but that does NOT mean they could not have passed the former spec. Again, look to Amsoil's offerings; anywhere you see ATF recommended for former DEX III app's, you could upgrade to ATD. But they do not recommend ATF for TES-295 applications. And both would be suitable for former DEX III applications!

Here's something else to know about DEX III, DEX VI and TES standards:
The fomer DEX III standard was primarily based upon moderate performance standards; it wasn't too demanding and it would allow for a broad range of base stocks. It was very similar to Ford's former Mercon spec, performance wise, and that's why you would see brands multi-market to both specs.

The DEX VI is a much more demanding performance standard, but it ALSO has a very specific chemistry package license requirment, so that a DEX VI product has to have that chemistry to pass the spec. There are EXCELLENT ATF products that don't pass this DEX VI license simply because they have a different vis and do not contain that particular chemistry package (that was initially only developed by one company for GM).

Allison's TES-295 is a VERY demanding performance standard, but it does not require any particular chemistry that I'm aware of. However, becaues the performance is so demanding, it's typically only successfully passed by products that have top end PAO stock (or perhaps group III, although I cannot prove/disprove this claim).

TES-389 is essentially an Allison standard that mimic'd the former DEX III performance specs, so that conventional oils could be used for lesser cost applications. It also addresses the whole "seal compatibility chemistry" issue for the Allison trannies. There is a long list of conventional lubes that meet this standard: https://fdlrd.swri.org/Allison/ApprovedFluidsList.aspx?Id=2
Anywhere you could use a TES-389 fluid, you could "upgrade" to a TES-295 fluid for longer intervals and higher performance.

Note that the fluid you referred to , Donax TX, is NOT TES-295 licensed, but it IS TES-389 licensed. Apparently it could pass the "lesser" standard, but not the higher standard at Allison!


So, it's true to say that a TES-295 could never attain a DEX VI license, but that's because it was never desgined or inteded to do so. TES-295 is a performance spec desgined for DEX III applications. DEX VI was desgined for thinner fluid applications, and is backwards compatible (only in some applications) to DEX III apps and it is very much a chemistry spec as well as a performance spec.

In equipment that was designed for former DEX III use, I would choose a TES-295 fluid every time over DEX VI if PERFORMANCE were the main deciding factor. There are, however, applications where the equipment was designed for thinner fluids and DEX VI would be more appropriate.

 

[ledslinger]

Shell Donax TX appears to be a TES 295 "clone" like Amsoil and Schaeffer. Do you know anything about Shell XHVI base stock?

 

[dnewton3]

No, sir, I don't, to be honest.

I should say that I hope I'm not coming off too strong here, because some of what I post is my opinion as I interpret the facts and data. But I've spent a LOT of time trying to work through this topic, as the owner of a Dmax/Allison with the manual t-case, and this has a direct effect on me.

I've made a lot of phone calls, done a lot of reading, and talked with a few people "in the know".

Take my posts as you will.

What I do know is that marketing hype pales in comparison to the facts of licensing standards. But one has to understand the applications to understand the benefits and limitations of those standards.

Here's my thoughts on the Donax TX. Probably a clone. But here's what I don't understand ...
If shell wanted to spend the time and money on a TES cert from Allison, why not go after the full monte? Why not get the TES-295 license? Did they try and fail? Or, did they just not try? Why offer it for sale as "suitable for use"? Because it is not licensed, that's why! So they were able to qualify the TX as TES-389. We can be assured it will function generally as a former DEX III would, and probably a lot better if they are willing to offer it as a "clone".

That's all we can really read into that ... we can read some facts at take them at face value, and then we have to make some inferences and go on faith.

The ATF I use in my Ally is DA-Lube AutoTrans-5. It's an unlicensed clone. It's made here in Indy, so I can get it locally for cheap, and drive to get it so there is no shipping costs. It's PAO; I called and asked the engineering team directly.

TES-295 fluids are required by Allison when you enter a maintenance contract with them for extended service. Past that, there is no "requirement" to use TES-295 licensed fluids. I feel that clones offer a great value for the money, with similar performance and less cost. There is no proof, because there is no license. But I'm willing to trust Amsoil, Schaeffers, DA Lube, etc that they make a product and market a product that will fulfill my needs. I don't "NEED" TES-295 fluids for a contractual obligation, but I can benefit from the extended drain intervals of the clones, for less cost.