Let Me Know if You Have Allison Transmission Fluid Questions

lunch surfer wrote:
I have an 05 dp with Allison 3000 tranny change filters at 5000 miles it has about 20,000 on the clock now. Should I change the transyn (synthetic oil) on age only now?

Lunch Surfer,

Check your transmission fluid first using advanced oil analysis that includes TAN (total acid number). There's a really good chance that it doesn't need to be changed. Change it based on scientific data, not on time or mileage.

I have an 05 dp with Allison 3000 tranny change filters at 5000 miles it has about 20,000 on the clock now. Should I change the transyn (synthetic oil) on age only now?

dsbsi wrote:
Hatman
I agree with you 100%. Drain the old fluid, install a new filter and refill with new oil and then unhook the cooler out to transmission line and start the engine and manually shift to reverse-1st-netrual-reverse 1st-netrual-stop the engine-add more oil-start the engine and repeat until oil runs out clear like new.

***REMEMBER***

One tiny speck of dirt could kill your transmission. Use a pressure air hose to clean the disconnect fitting before and after loosening. Then proceed to open the line and run the old oil out the cooler line.

Plan on needing about the same amount of oil as is required to overhaul the transmission plus a couple quarts more for the cooler.

When you know your Allison has "TRANSYND OIL" forget about the drain period for several years and then oil sample analysis will tell you when to change it.

Allison will not endorse this procedure because of the dirt risk but how much dirt entered the transmission all the years they required us to remove the oil pan and the valve body etc.to change the filter?

Hatman,

Allison field testing showed that (2) changes (without the need for flushing the torque converter and cooling system) were enough to get the expected life from TranSynd.

Hatman
I agree with you 100%. Drain the old fluid, install a new filter and refill with new oil and then unhook the cooler out to transmission line and start the engine and manually shift to reverse-1st-netrual-reverse 1st-netrual-stop the engine-add more oil-start the engine and repeat until oil runs out clear like new.

***REMEMBER***

One tiny speck of dirt could kill your transmission. Use a pressure air hose to clean the disconnect fitting before and after loosening. Then proceed to open the line and run the old oil out the cooler line.

Plan on needing about the same amount of oil as is required to overhaul the transmission plus a couple quarts more for the cooler.

When you know your Allison has "TRANSYND OIL" forget about the drain period for several years and then oil sample analysis will tell you when to change it.

Allison will not endorse this procedure because of the dirt risk but how much dirt entered the transmission all the years they required us to remove the oil pan and the valve body etc.to change the filter?

Hi Tom:

I've read through this thread (21 pages) as I'm picking up my new-to-me 1999 American Eagle this coming weekend and will be changing the transmission fluid and filters when I get it home.

Here's my question: If draining the fluid only removes about half of it, then you end up with a 50/50 mixture of TranSynd and old fluid after the initial change. If you repeat, you then end up with a 75/25 mixture of new vs. old, repeat again and it's 87/13, etc. I'm not an engineer, but that's just basic math.

Since you're recommending two changes, is the 75/25 mixture good enough for the long intervals now suggested?

I understand not everyone wants to pull off an oil cooler line and pump out the fluid (although I've done it on my gasser and it's pretty easy), but it sure seems like the only way to really get close to 100% of the old fluid out, not to mention it's much more cost effective. I would think even if you had to pay someone the extra labor to pull the line and pump, it would still be a wash compared to the cost of draining two times and the extra fluid. And you end up with nearly 100% fresh new TranSynd, versus only 75% using the drain twice method.

Thoughts?

rvrepairnut wrote:

jmanrambler wrote:
I have a Workhorse W24 chasis with the Allison Transmision. What is the service interval for changing the fluid. I only have 3700 miles on it. Should it be changed after a certain amount of months? Its a 2006.
Thanks

If U have the 295b syn oil your ok but for
Best information available bar none
copy and paste this Allison maintanance manual
http://www.allisontransmission.com/servlet/DownloadOnDemand?ApplicationID=155&DownloadID=5

PS: I wrote most of the fluid recommendations that appear in this document before I retired from Allison.

Jim@HiTek wrote:

Jim@HiTek wrote:
Thanks for your advice and help here on the forum, hzjcm8.

I had my Allison 4 speed back flushed and filled with Transnyd at 136,000 miles back in '07 at a bus repair shop that was just getting into RV's. They used a big fancy machine and told me they flushed it until the fluid was the right color, 3-4 times if I remember. At that time they told me there was no need to replace the tranni filters as the back flush would clean them like new.

Is that true?

At 142K miles, I developed a hydraulic leak in the boondocks of Canada. I had a couple quarts of Transnyd that I used up along with a couple pints of ATF stop leak I bought as I limped several hundred miles to Prince George. Also added regular ATF as needed along the way (small stores don't usually carry transnyd).

Had a leaking hose replaced and the tranni topped off with more transnyd. The mechanic told me it was OK to mix the standard ATF, Stop Leak, and the Transnyd but I would like to hear that from you.

Should I have it re-flushed, or is it OK with those other fluids in there?

Thanks!

Still wondering about this...it was definitely leaking tranni fluid from a tranni cooler hose. Once hose replaced, did not have to top off the tranni fluid level anymore.

Jim@HiTek,

No. That is not true. You can force new fluid through the main and lube filters. That's what the transmission pump does. But, you cannot "back flush" them like a "water softener" sediment bed. That would require the system to pump the fluid backwards from the inside of the filter to the outside of the filter. They didn't know what they were talking about.

Now, with regard to the fluids and "Stop Leak". Regular ATFs will mix with TranSynd. However, these regular ATFs aren't very stable from a viscosity standpoint and will lose viscosity over time. My bet is that your viscosity is low right now. The mix won't hurt anything but it will continue to degrade and lose viscosity over time. Also, I'm not sure about the effect of the "Stop Leak". It may just be a seal swell agent that wouldn't help with hose leaks. Also, it could be that the hose leak was caused by the use of the flushing machine since they would have had to disconnect and reconnect the cooler circuit in order to flush the transmission. I do not ever recommend the use of a flushing machine. You're always better off doing a double drain and refill.

Here's my recommendation. Drain the transmission, fill it with TranSynd, drive it for 1/2 hour to circulate the mixture through the torque converter, controls and cooling circuit, then drain it again, install new Allison "High Capacity" and refill it with TranSynd. This will give you the dose you need for the extended drain intervals. You can run it up to 300,000 miles (pretty much fill for life) and change the filters at 75,000 mile intervals. Check it once a year with oil analysis. I can counsel you on that since that's what I do now since retiring from GM and Allison.

This will minimize your problems and get you back on the road to "worry free" operation.

Call me on my cell phone if you'd like to talk. I can be reached at 317-430-3029.

And my analysis indicated I didn't already have Transyd in there :-(

Jim@HiTek wrote:
Thanks for your advice and help here on the forum, hzjcm8.

I had my Allison 4 speed back flushed and filled with Transnyd at 136,000 miles back in '07 at a bus repair shop that was just getting into RV's. They used a big fancy machine and told me they flushed it until the fluid was the right color, 3-4 times if I remember. At that time they told me there was no need to replace the tranni filters as the back flush would clean them like new.

Is that true?

At 142K miles, I developed a hydraulic leak in the boondocks of Canada. I had a couple quarts of Transnyd that I used up along with a couple pints of ATF stop leak I bought as I limped several hundred miles to Prince George. Also added regular ATF as needed along the way (small stores don't usually carry transnyd).

Had a leaking hose replaced and the tranni topped off with more transnyd. The mechanic told me it was OK to mix the standard ATF, Stop Leak, and the Transnyd but I would like to hear that from you.

Should I have it re-flushed, or is it OK with those other fluids in there?

Thanks!

Still wondering about this...it was definitely leaking tranni fluid from a tranni cooler hose. Once hose replaced, did not have to top off the tranni fluid level anymore.

I recently had a laboratory analysis done on my automatic transmission fluid. I remembered this thread and other similar ones on other RV forums. When I had received my results, I communicated with Tom Johnson, the former Allison Fluids Engineer who has been so helpful here answering transmission questions In the process of that communication I came to realize that Tom's business in retirement includes all kinds of fluids laboratory analysis. I felt badly that I had used another lab, but he was still thoroughly helpful I will use Tom's labs going forward. Maybe the rest of you already realized Tom had this capability, but if you didn't like me, I hope you will also consider using his services in the future. I have no vested interest in his business; I just thought others might want to know of his capabilities as he has been so helpful to RVers.

Here is the link for his company. JG Lubricant Services