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Former Allison Fluids Engineer (Here to Help)

617K views 694 replies 213 participants last post by  OkDually  
#1 ·
Hi folks,

My name is Tom Johnson. I was the former Transmission Fluids Engineer for Allison Transmission from 1990 until my retirement in 2009. I worked to develop and release TranSynd for Allison over a 10 year period and I also wrote the Allison TES-295 and TES-389 specifications. I had full responsibility for approval of all transmission fluids for Allison products on a world-wide basis. Since Allison was owned by GM for decades, and as part of my job at Allison, I also served on the ATF Committee for General Motors for several years. And, because Allison produces most of the transmissions for the US Army, I was also a member of the Engine Oil Review Committee for SAE Performance Review Instittute (formerly the Lubricant Review Institute.

These are my credentials. I'm here to help with your questions and to settle any arguments concerning TranSynd, Allison fluid specifications, DEXRON-III, DEXRON-VI, oil formulations, etc. So, as long as I'm not absolutely flooded with stuff, I'll try to keep up.

PS: I couldn't be involved in these forums while in my official capacity at Allison but I always thought I'd get involved once I retired. I own my own oil and coolant analysis business now and do consulting for the oil and additives industry on the side.
 
#2 ·
Thanks for your stepping forward. I guess the most common question would be; Is transynd the best route to take? I recently drained my 03 and swapped to Transynd.
 
#7 ·
Thanks for your stepping forward. I guess the most common question would be; Is transynd the best route to take? I recently drained my 03 and swapped to Transynd.
Castaway,

Yes ... it's still the best option. Telll others to forget about DEXRON-III. They're no longer approved or monitored by any OEM, so I'd stay away from them. DEXRON-VI is no longer approved either since Allison is no longer part of GM. Not just because they sold Allison but because now Allison has no voice in any DEXRON-VI changes that GM may decide to do.

Thanks for your question.
 
#4 ·
I just had my trans fluid changed. They put dexIII in. 07.5 3500.
Will this screw up my trans?
Put about 400km on before I found out.
Thanks for input.
Have a feeling you will be a great help to everyone on here.


Martin
 
#5 ·
I just had my trans fluid changed. They put dexIII in. 07.5 3500.
Will this screw up my trans?
Put about 400km on before I found out.
Thanks for input.
Have a feeling you will be a great help to everyone on here.


Martin
It won't screw up the transmission but it will degrade TranSynd if that's what was in it. It will eventually lower the viscosity. I'd if you were running TranSynd, you should change it out and reinstall TranSynd. No need to change filters.
 
#9 ·
Thanks Tom! That was quick.
No, it was dexVI. Not transynd.


Martin
If it's DEXRON-VI, the viscosity will still drop over time. If you have the newer DEXRON-VI compatible seals then DEXRON-VI is OK (just no longer recommended in the future).
 
#10 ·
thanks for your exsperince and welcome
 
#11 ·
When did allison update the seals? Reason I am asking is most GM dealer only carry dex 6 now. When some one ask for a trans fluid exchange dex 6 goes in everthing. So that could be bad for the ollder ally correct?
 
#12 ·
Goodwrenchtech,

For anyone unsure about their seals compatibility with DEXRON-VI, I recommend they call the Allison Tech Support Line at 1-800-252-5283 and check your transmission serial number. Allison issued serial number break points for DEXRON-VI compatible seals. I, of course, can't remember the S/Ns. This would be a good "STANDARD PROCEDURE" to implement at all GM dealers. You should forward this to the GM dealer organization through your Sales/Service folks to help out Allison owners.
 
#17 ·
All 06+ GM's came with DEX6, but the ALLISON S/N breakpoint wasn't until mid year 06. TRANSYND is a good fluid, but speaking from experience it doesn't work well in a performance built ALLISON with the ALTO clutches. SO keep this in mind that quite a few of teh guys here are NOT running ALLISON clutches anylonger, and this changes things a bit. TRANSYND is a very smooth shifting fluid sompaired to DEX3, but with ALTO clutches this isn't good.
 
#22 ·
Alto Clutches



thefermanator,

So, I'm guessing your not covered under warranty. Which is OK. I'm guessing the Alto clutches have an increased coefficient of friction for harsher (firmer) shifts. Don't know much about them but what fluid are you running then? I could blend up something special for you guys if there's enough interest. I'd have to run some clutch tests though.

Your comments?
 
#19 ·
im looking at an 07 cc/lb 4x4 if im not mistaken from what ive read so far the seals would be compatible with the transynd fluid? also it only has 52K miles, out of curiousity should i change out the trans fluid for the transynd or leave it as is?
 
#24 ·
WhiteRam,

If your owner's manual says DEXRON-VI then it's OK. Otherwise, change to TranSynd but do a drain, refill, drive it for 100 miles, drain again and refill again. This should get you almost "fill for life" but check it periodically through oil analysis if your unsure.
 
#20 ·
Changing to transynd

Hi Tom glad I found this site, my lucky day.:D
Here id my situation I have an 08 Chevy Duramax.
I recently had a local shop service the Ally trans and he dropped the pan changed the internal filter and external filter and refilled with DexIII and used an additive to "make it identical to Dex VI". I had this done aprox 500 miles ago.
Here are my questions.
1) If I change to Transynd do I need to change the filters again.
2)Can I just empty the pan and add Transynd and run for 1k to 2k miles then empty and add Transynd again without hurting anything?
 
#23 ·
Hi Tom glad I found this site, my lucky day.:D
Here id my situation I have an 08 Chevy Duramax.
I recently had a local shop service the Ally trans and he dropped the pan changed the internal filter and external filter and refilled with DexIII and used an additive to "make it identical to Dex VI". I had this done aprox 500 miles ago.
Here are my questions.
1) If I change to Transynd do I need to change the filters again.
2)Can I just empty the pan and add Transynd and run for 1k to 2k miles then empty and add Transynd again without hurting anything?
J658,
First, there's no such thing as a DEXRON-VI additive. All ATF's are "fully formulated" meaning they contain all necessary components to pass the OEM specification. In the case of DEXRON-VI, once they pass the tests and get a GM license, they can not be reformulated or changed in anyway unless the GM ATF Committee agrees. I know because I sat on that committee for a number of years. DEXRON-III fluids are obsolete and are no longer licensed or monitored. So, if you purchase a DEXRON-III (mostly known as D3M today .... stands for DEXRON-III/MERCON), all bets are off on the quality of the product.

No need to change filters. They'll be unaffected by the fluid. Yes, change to TranSynd, run it awhile and drain and refill again and you'll be ready to go. Use oil analysis to determine when to change (probably 100,000 miles or more).
 
#27 ·
DEX VI is a synthetic base fluid, so DEX III couldn't be made to DEX VI. ALL ALLISONS are compatible with TRANSYND as it is basically a synthetic DEX III as I understand it with a unique additive package to it. It worked well for me in most regards, but after going back to a DEX III type fluid i got MUCH crisper shifts and firmer lock-up as well as a much more positive feel when I put it in gear.

Heres some good reading regarding the ALLISON in performance applications and what fluid.
http://www.duramaxdiesels.com/forum/showthread.php?t=19666
 
#31 ·
MaxPF,

You are correct. DEXRON-VI is not synthetic. It is made from a blend of Group II and Group III base oils plus the additives package. It does not contain any PAO (polyalphaolefin) which would make it a "true synthetic" Group IV like TranSynd and the other TES-295 approved products.
 
#33 ·
Hello and welcome Tom. I here lots of talk about Transynd and Tes295, what about Tes389 do you not recommend it?

I have an 06 6 speed that specs Dex VI in both the owners manual and on the dipstick but based on the serial number on the trans I am before the compatible seals were installed (11/12/2005 build) I have Castrol HD trans fluid available at my work that is TES389. Would this be OK

Thanks,

Todd
 
#38 ·
Hello and welcome Tom. I here lots of talk about Transynd and Tes295, what about Tes389 do you not recommend it?

I have an 06 6 speed that specs Dex VI in both the owners manual and on the dipstick but based on the serial number on the trans I am before the compatible seals were installed (11/12/2005 build) I have Castrol HD trans fluid available at my work that is TES389. Would this be OK

Thanks,

Todd
Todd,

I actually wrote the TES-389 spec. It's getting a little old now and we never got any more approvals after the first few made it through the test. That's why it's such a short list. If you read the spec (it's on the Allison website) you'll see that the fluid had to have had a valid DEXRON-IIIH license and then it had to run the Viton seal test for compatibility.

So ..... bottom line is this. TES-389 fluids are compatible with all Allison model year seals (as well as all GM model year seals). However, they are still all DEXRON-IIIH fluids so they have a relatively short life due to viscosity shear. This means they lose viscosity over a relatively short time so the drain intervals are much shorter to allow for the viscosity change and ensure it doesn't get too low before you change it.

I'm working on a new fluid that will do 100,000 miles and sell for around $10/gallon less than TranSynd or the other TES-295 fluids. It will take me another 6 months or so to develop it but then I plan to make it available across the US. Interested ..... ????
 
#34 ·
Tom - thanks for being part of the forum. Nice to have an individual with direct Allison experience.
Question from me - is a deep pan needed for the Allison transmission? I would think changing to TES 295 approved fluid would be the best option. I am pulling a 12,000 lb fifth wheel. Reason I am asking - I will be changing the fluid to Mobil Delvac Synthetic ATF but have not purchased the deep pan yet.


2011 Chevy Silverado 3500HD CCLB SRW LTZ 4X4 DA Blue Granite Metallic, Bed Rug bed liner, Luverne SS running boards, PML diff. cover, Air Lift air bags, Handy fifth wheel tail gate.
Towing: 2009 Montana Mountaineer 347THT Toy Hauler.
Previous DAs:
2005 Chevy Silverado 3500 CCLB SRW LT 4X4 DA Silver Birch Metallic
2004 GMC Sierra 2500HD EXLB SE 4X4 DA Sand Beige Metallic
 
#41 ·
Tom - thanks for being part of the forum. Nice to have an individual with direct Allison experience.
Question from me - is a deep pan needed for the Allison transmission? I would think changing to TES 295 approved fluid would be the best option. I am pulling a 12,000 lb fifth wheel. Reason I am asking - I will be changing the fluid to Mobil Delvac Synthetic ATF but have not purchased the deep pan yet.

Norskeole,

I'd stick with the shallow pan and use oil analysis to tell you if the fluid is holding up to the temperature. I'll bet TranSynd is all you need but oil analysis will verify it. Send me a PM and I'll tell you who to use for oil analysis.
 
#36 ·
Hello, and welcome Tom. My transmission came with DEXRON-VI (I confirmed this with GM) and the vehicle has a manufacture date of 04/06 and the transmission S/N indicates it is one of the early ones before the seal change. In 06/10 (4 years with DEXRON-VI) I changed the fluid to Transynd. I added about 3 ½ gallons using a method that also flushed out the cooler lines and cooler. It is not leaking now. Do you think I changed the fluid in time to prevent any future seal problems? Can you describe the problems that may occur in the earlier seals when using DEXRON-VI?

Thanks
 
#40 ·
Hello, and welcome Tom. My transmission came with DEXRON-VI (I confirmed this with GM) and the vehicle has a manufacture date of 04/06 and the transmission S/N indicates it is one of the early ones before the seal change. In 06/10 (4 years with DEXRON-VI) I changed the fluid to Transynd. I added about 3 ½ gallons using a method that also flushed out the cooler lines and cooler. It is not leaking now. Do you think I changed the fluid in time to prevent any future seal problems? Can you describe the problems that may occur in the earlier seals when using DEXRON-VI?

Thanks
It's dependent upon time and temperature and would be extremely difficult to predict your actual seal condition. The affect results in hardening the surface of the seals that could lead to surface cracks. As far as I know, Allison has not conducted testing to determine if TranSynd can correct any hardening but I personally think it's probably irreversible. I wouldn't worry about it. If you see leaks at some point, you can question it based on the info you have on S/N break points and the fact that GM told you it contained DEXRON-VI.
 
#37 ·
Tom, what are your thoughts on the Transynd clones such as Amsoil ATD?
 
#39 ·
Chinook,

I'm not here to judge or "bad mouth" any products .... but, if it's not on the TES-295 list (on the Allison website), I don't recommend it. If these "look alike" fluids meet the TES-295 performance specification like they claim, why not just run the performance specification and get a license?

PS: You'll hear talk about Allison not allowing folks to get a license and that we tore down the test stand. These statements are incorrect. Allison released the specification to the independent test labs so they have always been capable of running the spec.
 
#45 ·
I've got an 03 duramax, so should I be leary as to change my fluid from Dex 3 to synthetic, TES-295 being the seals could leak?

I'm almost at 100k miles so I'm looking at changing it. Should I change the internal filter while I'm at it?

I've got 5 gallons of Schaeffers oil ready to put in just trying to get some questions answered.

My grand father worked for allison years ago when they were developing the allison transmission for the M1 tank. He told me some good stories.

Thanks for your help and answering questions on the board, we all appreciate it.

Yellowchevy
 
#46 ·
I've got an 03 duramax, so should I be leary as to change my fluid from Dex 3 to synthetic, TES-295 being the seals could leak?

I'm almost at 100k miles so I'm looking at changing it. Should I change the internal filter while I'm at it?

I've got 5 gallons of Schaeffers oil ready to put in just trying to get some questions answered.

My grand father worked for allison years ago when they were developing the allison transmission for the M1 tank. He told me some good stories.

Thanks for your help and answering questions on the board, we all appreciate it.

Yellowchevy
Switching to TRANSYND was never an issue with any of teh ALLISONS as it is fully backwards compatible, DEXVI is the fluid in question as it has not been found to be fully backwards compatible and to be a marginal fluid to begin with for the application.
 
#52 ·
hzjcm8: I want to thank you for what you have done with Allison for the Army. I can tell you that I experienced very few problems associated with ANY Allison transmission. They prove to be very dependable and Army vehicles are demanding.
Allison has definitely proved itself.
GenBiltstein,

Thanks. Allison transmissions are pretty much "bullet proof". No pun intended. As a veteran (USAF 1968-1972) I am proud to say that I was a part of Allison and I served on the US Army's Engine Oil Review Committee for several years.

Have a good one !!!
 
#48 · (Edited)
Tom, I have a 2001 Allison with 175K miles on it. I have no idea what is in it now. Can you give me your recommendation on what fluid to use when I change it? I am assuming TranSynd is 1.. but what about the others that are easier to find?
1.?
2.?
3.?

thanks!
 
#51 ·
Tom, I have a 2001 Allison with 175K miles on it. I have no idea what is in it now. Can you give me your recommendation on what fluid to use when I change it? I am assuming TranSynd is 1.. but what about the others that are easier to find?
1.?
2.?
3.?

thanks!
jrbarber,

You can't go wrong with a TES-295 product. TranSynd is only available through the Allison dealer/distributor. For the nearest one, look on the Allison website under the service area. It lists all the dealers and distributors in North America. I would guess the other TES-295 fluids may be a bit cheaper since you don't pay the dealer distributor markup but I'm not sure about that. My knowledge is more on the technical side than the sales side so I'm not familiar with pricing. Though my gut feel is somewhere around $25-$30/gallon for a TES-295 product. The long drain intervals makes it worth the money .... not to mention the performance and durability.

Thanks !!