transmission fluid change

thanks for all the super information and guidelines. I appreciate it so very much.

Transynd will turn an orangeish color after time. This is normal.
Dex III will remain very red in color (unless it's burnt and it will look brown and smell burnt if so).
This might give you an idea of what you have in your tranny, but not definitive.
Allison recommends a change of fluid and filters at 5,000 miles initially, then fluid and filters every 25,00 miles or 12 months if non-Transynd. If Transynd, 100,000 miles or 48 months on the fluid and 50,000 miles or 24 months on the filters.
I'd change it now so you'll know and have a baseline to go forward with.

OK, it may be 12 years old on original fluid and filters.

Were it me-- no brainer, change filters and go with Transynd.

If you want a real postgraduate education on Transynd and the Allison transmission, go to Tom Johnson's thread and read the 400+ posts. These are what the above threads are referring to. Absolutely fascinating, especially when you realize you're getting the info right from "The Horses Mouth" as it were. His lab can do the type testing you need and if you also get a particle count done, you can see if you need to change the fluid if it's Transynd, regardless of the length of time or mileage it's seen.

rgatijnet1 wrote:

FIRE UP wrote:
lj2654,
As has been stated, there is no test that the average motor home owner can do to determine if you have Dexron or Transynd. An oil sample sent to a reputable lab can tell for you. Now, if you're relatively sure you've got Dexron, and, want to change to Transynd, then here is the procedure direct from a member on here and, IRV2, who was instrumental in the development of test procedures for many Dexron products and, synthetic products including Transynd.

This is a fairly expensive way to do it but, it's the way, according to him, that many of the service centers do it.

1. Drain existing trans fluid completely and DO NOT CHANGE FILTERS AT THIS TIME!!!
2. Replace with Transynd an equal amount of fluid.
3. Drive your motor home for a minimum of around 30 - 45 minutes, letting it shift as often as possible.
4. Drain all that fluid out, remove filters.
5. Install new filters and, replace with NEW TRANSYND again to correct level.

You are wasting money by replacing filters on the first change. By only driving around 30-45 minutes, that, according to him, is plenty of time the first round of Transynd to start to replace the exiting Dexron. Then, with the second round of Transynd, the experts say that, the tiny bit remaining Dexron, will have no effect on the operational characteristics of the new Transynd. And, after you've done the second round of Transynd, you're good for right at 100K miles before needing another trans fluid change. I'll try and find his member user name and repost so you can see all he has to say about Transynd and other important data on other fluids including Dexron.
Scott

That is all good information and spot on. The only thing that I would add is that you are good for the long extended fluid change, IF, and this is a major IF, you do not overheat the fluid. If during a long climb up a steep mountain road, pulling a toad or trailer, and you seriously overheat the transmission fluid, then the life of your Transynd will drop to maybe only a few thousand miles. On some transmissions there is a sensor to monitor transmission fluid temperature. I have a sensor on my Allison transmission and I would know in an instance if I overheat my fluid enough to affect the fluid life.

This caveot is one of many reasons to do an annual sample test of your fluid.

FIRE UP wrote:
lj2654,
As has been stated, there is no test that the average motor home owner can do to determine if you have Dexron or Transynd. An oil sample sent to a reputable lab can tell for you. Now, if you're relatively sure you've got Dexron, and, want to change to Transynd, then here is the procedure direct from a member on here and, IRV2, who was instrumental in the development of test procedures for many Dexron products and, synthetic products including Transynd.

This is a fairly expensive way to do it but, it's the way, according to him, that many of the service centers do it.

1. Drain existing trans fluid completely and DO NOT CHANGE FILTERS AT THIS TIME!!!
2. Replace with Transynd an equal amount of fluid.
3. Drive your motor home for a minimum of around 30 - 45 minutes, letting it shift as often as possible.
4. Drain all that fluid out, remove filters.
5. Install new filters and, replace with NEW TRANSYND again to correct level.

You are wasting money by replacing filters on the first change. By only driving around 30-45 minutes, that, according to him, is plenty of time the first round of Transynd to start to replace the exiting Dexron. Then, with the second round of Transynd, the experts say that, the tiny bit remaining Dexron, will have no effect on the operational characteristics of the new Transynd. And, after you've done the second round of Transynd, you're good for right at 100K miles before needing another trans fluid change. I'll try and find his member user name and repost so you can see all he has to say about Transynd and other important data on other fluids including Dexron.
Scott

That is all good information and spot on. The only thing that I would add is that you are good for the long extended fluid change, IF, and this is a major IF, you do not overheat the fluid. If during a long climb up a steep mountain road, pulling a toad or trailer, and you seriously overheat the transmission fluid, then the life of your Transynd will drop to maybe only a few thousand miles. On some transmissions there is a sensor to monitor transmission fluid temperature. I have a sensor on my Allison transmission and I would know in an instance if I overheat my fluid enough to affect the fluid life.

lj2654,
As has been stated, there is no test that the average motor home owner can do to determine if you have Dexron or Transynd. An oil sample sent to a reputable lab can tell for you. Now, if you're relatively sure you've got Dexron, and, want to change to Transynd, then here is the procedure direct from a member on here and, IRV2, who was instrumental in the development of test procedures for many Dexron products and, synthetic products including Transynd.

This is a fairly expensive way to do it but, it's the way, according to him, that many of the service centers do it.

1. Drain existing trans fluid completely and DO NOT CHANGE FILTERS AT THIS TIME!!!
2. Replace with Transynd an equal amount of fluid.
3. Drive your motor home for a minimum of around 30 - 45 minutes, letting it shift as often as possible.
4. Drain all that fluid out, remove filters.
5. Install new filters and, replace with NEW TRANSYND again to correct level.

You are wasting money by replacing filters on the first change. By only driving around 30-45 minutes, that, according to him, is plenty of time the first round of Transynd to start to replace the exiting Dexron. Then, with the second round of Transynd, the experts say that, the tiny bit remaining Dexron, will have no effect on the operational characteristics of the new Transynd. And, after you've done the second round of Transynd, you're good for right at 100K miles before needing another trans fluid change. I'll try and find his member user name and repost so you can see all he has to say about Transynd and other important data on other fluids including Dexron.
Scott

If there is any chance the fluid was changed at some point in its life to Transynd, then you could pull a fluid sample and send for testing. There is no test for Transynd but since the fluid has not been changed in the last year, if the viscosity is still above 7 with little sign of oxidation then you probably have Transynd. If that's the case just change the filters, top up the fluid and test again in a year.

If you're pretty sure you have DexIII then do a fluid/filter change and a year or so down the road do the fluid/filter change again. You will then be good for 3 years on the filter at which time I would test the fluid again. The Transynd will probably be good for a long time with just a top up when you change filters every 3 years.