Dextron 6 - M35A3

[MATT]

FYI

I knew this was coming- I had a allison 1545 auto trans out of a A3 go bad. Fluid smelled burnt and was dark. I took it to the transmission guy and he said the front pump was toast, he eventually found a new front pump for $700.

He said parts for the 1545's are going to be hard to find since it's obviously a military trans. He recommended changing the trans over to a 545, the civilian version. My only concern is the length of the 545, it was hard enough getting the 1545 removed from the truck!

I told him we have been draining the motor oil from the trans and replacing it with Dextron 3, he said "good" but he HIGHLY recommends running Dextron 6 in these trucks. So, I'll be running Dex 6 in all our trucks from now on.

 

[BKubu]

Have you called around to some of the bigger dealers about a take-out transmission? I would start with White Owl in NC. They have a lot of parts and they are priced reasonably...usually. Good luck.

 

[mktopside]

Here are some for sale. Prices aren't that bad.

HeavyTruckParts.Net - Results for Allison AT545 Transmission Assembly

I don't know much about DEX 6, what about Allison's Transynd fluid?

Do you mind explaining the conditions in which it failed? Just driving? Off road? heavy load?

 

[patracy]

I'd go with Transynd fluid. Good stuff.

 

[lonegunman]

I'm running Dex in mine with zero problems. The first thing I did after picking the truck up was service the trans, drop the pan and replace both the internal and external filters. The temps dropped considerably.

 

[shovelheadmike]

I'd go with Transynd fluid. Good stuff.

When I first got my A3, I took it to the local Allison dealer to have the motor oil replaced with Transyn. However, they told me that they did not recommend doing that as it incompatible with any other fluid. Said enough of the old could not get flushed from the torque converter. They put Dextron 3 in it and changed the filter.

 

[patracy]

Hmmm interesting. While it's true you'll never drain several quarts out of the transmission (Torque converter, valve body, pump), I never had any problem out of my chevy duramax/allison. It actually helped it with shifts and eliminated the TQ shutter I was getting in 5th locked when I'd load the engine.

 

[glcaines]

Dexron is a product licensed by GM. All Dexron III licensing expired at the end of 2006. Dexron VI is the current Dexron product and is backwards compatible with all ATF applications requiring a previous version of Dexron. That being said, I am going to change out the fluid in my A3's Allison with TranSynd a product made by Castrol. This is what Allison recommends and I have several friends that have told me that Allison transmission work better and last longer with this more expensive ATF fluid.

 

[jamboly]

I know this is not an M35 topic, but this thread is only thing I could find where someone might be able to help me out. I just picked up an M920, with the transmission fluid drained. So I was looking to find some transmission fluid to put in it. LO calls for 10W MIL-L-2104C. SHELL RIMULA oils meet that spec. (Rotella 15W-40 meets 2104F). It has a CAT D-7155 "semi" automatic Transmission in it. Anyone want to take a stab at recommendations as to what to use?

 

[glcaines]

I know this is not an M35 topic, but this thread is only thing I could find where someone might be able to help me out. I just picked up an M920, with the transmission fluid drained. So I was looking to find some transmission fluid to put in it. LO calls for 10W MIL-L-2104C. SHELL RIMULA oils meet that spec. (Rotella 15W-40 meets 2104F). It has a CAT D-7155 "semi" automatic Transmission in it. Anyone want to take a stab at recommendations as to what to use?

I would contact Caterpillar and ask them.

 

[4x4 Forever]

I would contact Caterpillar and ask them.

Cat knows best what to use in their equipment. You can use this info and cross reference it to other manufacturers products...

 

[Floridianson]

(Rotella 15W-40 meets 2104F). I Anyone want to take a stab at recommendations as to what to use?

What I use is the rotella 15-40 just takes awhile for the trans to warm up with 5 gal. in there

As for the A3 good reading and I have not changed mine out yet but I see that is comming.
The outher thread had where we drop the return line from the cooler and pump it through till the color changes.
So here I think we could get a good change out of the tq converter.
I will to start leave the old filter in place as it has low miles and just drain oil. The I wil refill with the same amount as I took out and if I can add 1 gal more and if the whole gal does not fit I will add what I can till it come close to the end of the dip stick tube. Then I will have the return line removed and a five gal buckett marked at one gal or what ever the amount I was able to fit in the trans as extra. Have someone fire it up and watch the buckett and when it come close to hitting my mark shut it down. I will keep adding and stoping till I have a good chang out.
I will try and put some miles on this oil change then go for another change but doing the filter along with compleat fluid change and I should be good
for life. If the post is correct about the Syn not mixing then Dextron 6 will be the oil I will run .
The reason in my mind about the filter change is the dextron is going to clean out the trans. so let it be with the old filter. This will cost more but to me will be a better job.

 

[Andydieselpower]

A3 transmissions

I have 2 take out 1545 A3 transmissions in stock. Both are tagged "good". Being sold as/is. $600 each.

Andy

 

[glcaines]

Dexron is a product licensed by GM. All Dexron III licensing expired at the end of 2006. Dexron VI is the current Dexron product and is backwards compatible with all ATF applications requiring a previous version of Dexron. That being said, I am going to change out the fluid in my A3's Allison with TranSynd a product made by Castrol. This is what Allison recommends and I have several friends that have told me that Allison transmission work better and last longer with this more expensive ATF fluid.

I just found out that although GM says that Dexron VI is backwards compatible with all ATF applications requiring a previoous version of Dexron, Allison apparently says that Dexron may not be compatible with some seals in older Allison transmissions and that if TranSynd is not available, an ATF corresponding to the previous Dexron III should be used since it is compatible with all seal materials in older Allison transmissions. I don't know what this means for the A3 transmission because I don't know what Allison considers to be an 'older' transmission.