Flushing 06 Allsion trans.

[Steve-Maine]

I went to dealer today and asked about flushing the auto trans on my 06 Duromax. All they can do is drain pain and refill and change filter. they sais this would replace only about have the fluid. it has 60,000 on truck. Would I be better to find someone who can do a complete flush with a machine.? Also is much of a job to replace seal where shiftine rod goes into auto trans.? Thanks for any help.

[dewfpo]

A pan drain and refill is the Allison recommended and approved atf changeout procedure. That being said, the ATF can still be changed out via the atf cooler line and that will likely remove 95+% of the oid atf at one time. Sorry I can't help with the shaft seal question.

 

DEWFPO

[gmtech4]

i believe the shifter shaft seal is removed with a special tool and installed with a special tool,

 

maybe a currant tech can copy and paste the SI for you ,ive been out of gm a few years and have no access anymore

[jake111]

Firstly, as DEWFPO said, but I would like to emphasize, DON'T FLUSH AN ALLISON WITH A MACHINE. This might be the #1 way to destroy it. I'll leave it to you to research further if you want to know everything it can screw up. For once, the dealer the was right.

 

Over a year ago, on another forum, I posted like this quote from the Allison website. The webpage may or may not still exist:

Effective January 1, 2007, General Motors no longer licenses DEXRON ®-III fluids. DEXRON ®-VI fluids may be used in the 1000 and 2000 Product Families transmissions beginning with S/N 6310670488 and 6320784373; . .

 

As I understand it, the 3rd digit is where the transmission was manufactured (or maybe the 1 is for the 1000 and 2 for the 2000?), so you would have to check the s/n cutoff using either the 631... or 632... range. I don't have the quote, but some of the seals in the older transmissions might not hold up with extended use of Dex VI.

 

GM claims that Dex VI is backwards compatible and can be used for most Dex III applications. "Dexron III" no longer exists because GM retired all licensing of that name. If I understood the Allison site, Allison has a spec they call TES 389 for fluids formerly known as Dex III, but those oil producers would have to apply for that spec to be on their label, and few have. There is a Mobil 1 ATF that says "for use in 2005 and older GM", which I assume is the same old Dex-III ATF that it use to say on the label.

 

2006 was the year where the serial number cutoff occurred. Before the cutoff, GM says "use Dex VI", Allison says "don't". Your choice. Also, since you have a 2006, you have to crawl under it, find the serial number tag, and see if you are pre- or post- Dex VI compatible.

 

BUT, for more $$ you can use an Allison spec'd TES-295 ATF (like Castrol Transynd or Mobil Delvac ATF which is different from Mobil1 ATF), which is a superior choice to anything else, and most people notice the difference. You can only get a TES-295 at a truck shop. (There might be a Deere TES-295 but I don't know what it's called.) In my area it's $40/gal. and it takes about 7.5 qts for a simple drain/fill. Also, the proper fill level is at or very near the BOTTOM of the "Hot" hashed area on the dipstick when the trans temp is 170*F. Otherwise, you find the transmission runs hotter than normal.

[Z45]

From a GM release

 

Dexron III is being phased out as a product name. It is being renamed Manual Transmission Fluid and carries p/n 88861800 U.S. (88861801 Canada).

 

 

[Diesail]

50k service is to drain from pan, change filter and fill. If you are worried that is not enough Allison’s recommendations to switch their transynd is to drain and change filter and fill. Drive about 100 miles, drain and fill again. No filter change on second drain. If switching to transynd Allison says you are now good to 100k on fluid. Sticking with GM fluid, drain, fill and forget about it. When was the last time you heard of an Allison failing?

[Black02Silverado]

Going the route the dealer said would be the way to go. It has low miles on it and that would get a good start on changing the fluid out. You can always do like posted above and drive it for a while and just drain the pan again and refill without changing the filter.

 

Another option for fluid is AMSOIL's ATF fluid which is for your application as well.

[chrisb1]

If you change your own fluid, use the transmission return line from the radiator. Drain the pan. Replace the external filter and be careful to clean and

replace the circular magnet. Replace pan bolt. Fill the transmission with correct fluid. Remove the return line clip and pull the return line from the transmission body and take the steel line and attach a two foot rubber hose (5/8in)into a 2.5 gallon bucket (preferably a clear container). Mark the bucket in half gallon increments. Place the hose into the bucket and have another person start the engine. Allow about two gallons of fluid to exit the hose. Stop and refill the transmission. Start the engine a second time and have the second person move the gear selector through the gears. Watch the fluid color. Very quickly, 2 gallons removed, the fluid will change cherry red. Stop the process. Replace the return line and clip. Refill the transmission to the correct fill line. With a clear, red fluid color, you will have changed all the transmission and converter fluid. Good luck!!

[newdude]

Jake111 has it right. Transynd would be the way to go in my opinion. Check dieselplace as well, as it is discussed often and is used quite a bit. Also, check out this link on dieselplace to the sticky forum with the former Allison engineer. If you have some reading time, its worth it. http://www.dieselplace.com/forum/showthread.php?t=420656