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Has the trans fluid debate been settled yet?

TechnoWeenie

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Or is it a 9mm vs .45 situation?:cool:

Got the 10wt camp that says 'look at the LO'
Got the 15w40 camp that says 'Whatever works'
Got the Dex3 camp that says 'It's the best choice for the price'
Got the Transynd camp saying 'This is what Allison says to use'


10wt camp says 'it's mil spec', says dex3 burns up trannies.
15w40 camp doesn't care.
Dex3 camp says 10wt camp doesn't know what they're talking about.
Transynd camp is... spending a lot of money.... :p


I converted my last 5 ton to dex3, and it failed shortly after... something I attributed to my mistaken adjustment of the trans linkage on the throttle cable. However, reading the horror stories on dex3 seems to be too coincidental.

Also, there's multiple specs... Allison says off road trannies should still use 10wt.. but then specs transynd for OTR applications...

The only thing that people somewhat seem to agree on is, if it's got 15w40 in it, change it to 10wt.
If it's got dex, keep it dex or switch to transynd.


Thoughts?
 
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Valley Rock

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Mine is full of Amsoil ATF, for two reasons ...

1- I got 4 or 5 gallons of it at a yard sale for 15 bucks .

2- it says right on the bottle that it is specifically for that Allison trans, does Allison know this ? I have no idea .

I don't believe that using ATF is going to cause failure, but if I'm wrong I can assure you that another auto trans is not going back in this truck unless it's free or close to it .

Automatics suck, this truck needs a 13 or 18 speed .
 
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Jbulach

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Mine had what I’m guessing was 10wt in it, and always shifted and work excellent, old fluid looked clean as well as the filter that I cut open. This is what I just put back in it after fluid and filter change, will let you know if it kills it.
IMG_5167.jpg
 

simp5782

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I've seen $200/5 gallons... From what I understand it's a newer, full synthetic version of dex3.
More additives. More protection. Longer service interval. Dex 3 in the 600 series allison I was getting 30k miles loaded and they were dead. 150k miles in the 700 series on Tes295 without issue with a 90k service interval. To me it's worth the double money for 3x the life and Lower temps

Coolers also help. Transmission fluid has an unlimited life below 180 degrees.
 

TechnoWeenie

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So, this brings up another question.

I went to go replace the trans filter (spin on) and noticed there are 3 different versions. One is for oil, the other 2 are 'low pressure hydraulic - transmission'.

It would seem to me that the original filter may be designed differently and require higher pressures?

Anyone know what pump line pressure is on MT654CR? :D
 

TechnoWeenie

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More additives. More protection. Longer service interval. Dex 3 in the 600 series allison I was getting 30k miles loaded and they were dead. 150k miles in the 700 series on Tes295 without issue with a 90k service interval. To me it's worth the double money for 3x the life and Lower temps

Coolers also help. Transmission fluid has an unlimited life below 180 degrees.
Good call.

I bit the bullet.

2023-07-06_100647.png
 

DampLemonade

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Mine had what I’m guessing was 10wt in it, and always shifted and work excellent, old fluid looked clean as well as the filter that I cut open. This is what I just put back in it after fluid and filter change, will let you know if it kills it.
View attachment 900398
Sorry to resurrect an old thread.

Hows the tractor fluid working for you? I'm getting ready to do a drain and refill on mine. I was looking at TM9-2320-272-10 the operations manual and based off the temperature ranges I'd naturally wanna lean towards the 15w40. The price between the 15w40 and 10w is pretty much negligible where I live. Any insight? 10w seems pretty restrictive on temperature, it gets well into triple digits here in the summer.

oil table.PNG
 

DampLemonade

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I know it's a little pricey, but, heard good things about this too (along with the TranSynd) was leaning going this direction myself
I'll prolly end up buying some TranSynd come spring time. My old trans fluid was in pretty gross shape, so the tractor transmission fluid i just dumped in there has at least gotta be better than what it was lol. Got it on sale for $60, and I've spent a lot of money on this truck in the last month so I just need the tractor fluid to hold for a few months haha
 

Defcon-1

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I know it's a little pricey, but, heard good things about this too (along with the TranSynd) was leaning going this direction myself:

View attachment 912129
View attachment 912130

Just as a followup, I switched over to this on the weekend (drain and refill + frame-filter change), and the 2nd to 1st hard downshift is completely gone. The truck also shifts way smoother up and down too, doesn't hang in gear as long. It's like driving a totally new truck without that hard CHUG and shake each time going from 2 to 1. Also, normal trans temp is now 165'/170' instead of 180'/185' even after running for 30+ minutes at idle and another 30+ minutes on road and highway speeds (although, this could also be partially attributed to the coolant-flush I did, have brand new coolant in there so probably more absorbent of the heat via the Trans/Coolant heat exchanger). I have another 5 gallon pail in the garage too, going to do another drain and refill (plus change pan-filter and governor filter and the frame-filter again) in the spring after I put some miles on it. The only thing I had an "issue" with is that it took a total of 15 qts to get to normal-full line on the dipstick instead of the 17 qts like the TM said. Originally took out 4 fresh qts from the 20 qt bucket, added all 16 to the transmission, but then had to take out another single quart via the Transmission/Coolant Cooler petcock to get it down to the right level. So far so good.
 
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DampLemonade

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2nd to 1st hard downshift is completely gone
I've been running my tractor transmission fluid for about two months now and it chugs a little bit on the 2-1 but otherwise seems to be doing okay. But like you said, still a massive improvement on what it used to be. I still plan on biting the bullet on the gucci Allison fluid this spring though.

Where are you buying your governor filter? It looks like only Oshkosh sells it and theyve been out of stock. I need to do that and my pan filter eventually
 

Defcon-1

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I've been running my tractor transmission fluid for about two months now and it chugs a little bit on the 2-1 but otherwise seems to be doing okay. But like you said, still a massive improvement on what it used to be. I still plan on biting the bullet on the gucci Allison fluid this spring though.

Where are you buying your governor filter? It looks like only Oshkosh sells it and theyve been out of stock. I need to do that and my pan filter eventually
Good to hear you had improved results as well, Sir. I actually didn't think that far out for the governor filter lol so didn't look into parts-purchasing for that. I did hear that they are cleanable so if I can't find one by the time I need to drain-and-refill again I will just do that, already have the TM's pulled and printed for both that and the pan-filter. Also, it was indeed a hard bullet to bite, so I feel yours and everyone's pain on the Gucci-fluid lol, but it does feel like a different truck now and I'm not embarrassed by that huge clunk and chug (basically a slam lol) anymore of 2-1, so that alone is worth it to me, for my dignity lol.
 
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Csm Davis

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I abuse my wrecker pretty hard and have not had a failure yet, 10 years now, 10wt. Unsure how anyone knows they have 15w40 it looks just like 10wt. BTW they were all filled with 10wt when new or rebuilt.
 
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