Hello all....Just curious how many of you have had your trannies flushed, and Transynd fluid installed in place of the Dexron. What are the benefits you noticed; I know it lubes better, but did it change or improve shift quality? I'm interested in the maximum protection for my "unbuilt" ally, and have been told this should be a must-do thing. Let me know your observations. Also, what did the flush cost you, and does the internal filter need to be changed? (Only 14,000 mi on my truck) Thanks!

I had mine done at 25k miles at the Detroit Diesel Allison shop down the hill from my house. Had them install a deep pan at the same time. IIRC, it was 4 gallons of Transynd at $30/gallon, about $150 labor, $45 deep pan, labor for the pan install, replacement internal filter with longer pickup for the deep pan. I think, all told, it was about $400 with tax, environmental charges, etc.

You do not have to replace the internal filter until the trans is overhauled.

Do it yourself with Mobil 1 synthetic and it'll cost you less than $100.
Go here to see how http://dieselplace.com/forum/showthread.php?t=1070

I gave my dealer my Amsoil trans fluid and it cost me $67.00 for flush & install. Trans always shifted good and still does.

Amsoil has two fluids available for the Allison. Torque-drive,a reverse engineered replacement for Transynd. Product code ATD @ $32.65/gal. And Universal ATF, product code ATF @ $8.00/qt. Prepered customer pricing reduces these prices by about 20%. www.lubedealer.com/oilrich/

i went with the amsoil torque-drive fluid, allison brand deep pan. disconnected return line from cooler at tranny and pushed on hose and ran to drain pan. filled pan and ran engine for short time. stopped and refilled pan. did this until new fluid came out of line.
took 5 gallons. I now will change pan fluid only every 100000 miles. Did this on my 99 gasser using amsoil dex III and never even a burp from the 4L80E and has 265000 miles. (this tranny has not had an fluid change in 200000 miles) Say what you will about amsoil products but i am a believer in their tranny fluids, gear-oils for my 40k trucks. You can take the fluid of your choice to quick lube and they charge around 50 dollars to flush and fill with your fluid.

The above mentioned method is in the DIY section. Works great... Used it twice myself.

As for the overpriced fluids, why not buy the Transynd at $120/5 gallon pail?? $24 per gallon. That is what Allison recommends. I would like to see the certifications from Allison on the other synthetic fluids!

This was the going price at a local allison dealer last month and two years ago too.

Go to www.allisontansmission.com for the straight story.

Allison does not recommend "flushing" this trans

They have specific guidleines for switching to transynd or any other synthetic. You must replace the spin on filter and drain the pan, refill the trans and then at the next change do the same process. After the second change with synthetic you can implement the extended change intervals available for synthetic.

You do not have to use transynd only if you wish to switch to syn. Any mfg that meets the C4 requirement is acceptable. Check Mobil 1 or other mfg websites for compliance.

Scott

For what it is worth, the tranny flush proceedure in the do it yourself section is now incomplete. I believe in the various forum conversions something happened. Another member (Enigma) had a complete copy of the original - except for the pictures - and recently retyped the whole thing for us (it is dated 02/02/2005). It can be found on page 2 of the following thread...

http://dieselplace.com/forum/showthread.php?t=22403

Years back it was said if you wanted a Turbo 400 to shift harder replace the Dexron fluid with Ford fluid. It had less lubricating qualities thus the clutches would grab better. Has anyone tried going in that direction instead of the synthetic to see it's effect on the Ally?

Mike maybe you can comment.