Allison Oil change

[mkebikecop]

I have a 2005 Mandalay with a Cat 350 & Allison 3000MH transmission. I have 39K miles.

I was told that I have Dexron III ATF in my transmission & I need to replace it at the change to TranSynd.

I am unable to find out how do i change the oil/filters to get it all out. Will TranSynd & Dexron III formula match? I know/was told that I will need 19 quarts during the change. How much is left in the transmission? Will I need to make two oil changes with some run-time between to get all the Dexron III out?

Ed

[Steve Ownby]

Ed,

Yes, the transynd and Dex III are compatible. There is no approved method to do a 100% change at one time. The Allison approved method is to change the filters and fluid by draining using the drain plug. Then consider the mixture as Dex III for drain schedule purposes. Some people drain again almost immediately and others run for 12 months or longer. After the change, consider the fluid as 100% Transynd. At that point use the Transynd drain schedule or start a program of fluid analysis to determine drain schedule.

[phays]

As Steve said. You get the real benefits from the change to Transynd after the second change. Allison has that information somewhere but I can't remember where nor can I find it again. Unless you are in a rush to get to all Transynd, I would run a season on the first Transynd change then do the filters and fluid change after that to get the full advantage of Transynd.

[Mr_D]

Quote:

Originally Posted by phays As Steve said. You get the real benefits from the change to Transynd after the second change. Allison has that information somewhere but I can't remember where nor can I find it again. Unless you are in a rush to get to all Transynd, I would run a season on the first Transynd change then do the filters and fluid change after that to get the full advantage of Transynd.

That's what I did. The transmission temp dropped 20° after both fluid changes.

The filters come with a good instruction sheet and all the gaskets. Easy to do if you can turn a wrench. Just watch the torque when doing the filter covers as the bolts (6 on each filter) can be stripped.

Here's a link to some of the info you need.

[mkebikecop]

Thanks to all for your response!

Ed & Key Largo (the cat)
2005 Mandalay 40e
2011 Jeep Wrangler Sarah

[ronmc]

Lot of advice about Transynd but Dexron has been used for many years with good results.If you want to spend a lotta money. Go ahead.

[Mr_D]

Quote:

Originally Posted by ronmc Lot of advice about Transynd but Dexron has been used for many years with good results.If you want to spend a lotta money. Go ahead.

True, but Dexron is no longer approved for use in new Allison transmissions. In fact it might not be approved for older transmission now as GM is not testing or certifying Dexron fluids anymore. A fluid manufacturer can call anything Dexron now or say it meets Dexron specs and no one can stop them.

[HeapBigEngin]

Quote:

Originally Posted by Mr_D True, but Dexron is no longer approved for use in new Allison transmissions. In fact it might not be approved for older transmission now as GM is not testing or certifying Dexron fluids anymore. A fluid manufacturer can call anything Dexron now or say it meets Dexron specs and no one can stop them.

Mkebikecop.....Tom, the Allison Engineer, was back on the forum several days ago.....not sure if he still is. He is a wealth of information, so I hope he is still onboard.

When I saw him back on the forum four days ago, I sent him a post/question re Allison's website info for Dexron III ATF. The Allison Approved Fluids website lists ALL of the Dexron ATF fluids, by manufacturer, that meet their TES-389 standard and are currently approved for use in their transmissions. The website also includes the Approval #. Tom assured me that any Dexron III fluid listed on that website meets TES-389 and is approved for use in Allison transmissions originally filled with Dexron III or currently using Dexron III. He also stated that, of course, the change intervals and costs vary between Dexron III and TranSynd. I currently use ExxonMobil ATF D/M. It is Dexron III ATF approved by Allison and meets TES-389. Don't know yet if I will make the change to TranSynd.

Hope this helps....

[Gary RVRoamer]

A 2005 motorhome chassis would have come with Transynd already installed anyway. Mandalay is built on a Freightliner XC chassis and FL has been using Transynd with their Allisons since 2003 or maybe even before.

[1ciderdog]

FYI My 2004 on a Freightliner chassis (built in 2003) came with Dexron.
Bob

[hzjcm8]

Quote:

Originally Posted by Steve Ownby Ed, Yes, the transynd and Dex III are compatible. There is no approved method to do a 100% change at one time. The Allison approved method is to change the filters and fluid by draining using the drain plug. Then consider the mixture as Dex III for drain schedule purposes. Some people drain again almost immediately and others run for 12 months or longer. After the change, consider the fluid as 100% Transynd. At that point use the Transynd drain schedule or start a program of fluid analysis to determine drain schedule.

Steve,

I'm back to stay. I took a vacation for awhile but now I'm back to answer questions. So, let's route everyone with Allison fluid questions back over to the original thread which I believe can be found at: http://www.irv2.com/forums/f125/former-allison-transmission-fluids-engineer-89293.html

[Gary RVRoamer]

My 2004 American Tradition, built on a 2004 Freightliner in December 2003, has Transynd. Maybe the RV manufacturer specifies it when ordering the chassis?

[Marty S.]

Valvoline still makes Dexron III and it DOES have the Allison approved TES number.

[Mr_D]

Quote:

Originally Posted by Gary RVRoamer My 2004 American Tradition, built on a 2004 Freightliner in December 2003, has Transynd. Maybe the RV manufacturer specifies it when ordering the chassis?

Yep, exactly.
The trans is tested with TranSynd, drained as much as possible then shipped to the chassis manufacturer who then fills it with whatever the chassis buyer spec's.