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hzjcm8's avatar
hzjcm8
Explorer
Apr 09, 2011

Let Me Know if You Have Allison Transmission Fluid Questions

Hi all, I've just joined Good Sam Club. I was the former Transmission Fluids Engineer at Allison Transmission. I held that position from 1990 until my retirement in 2009. Let me know if you have...
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Jarlaxle's avatar
Jarlaxle
Explorer II
Apr 26, 2011
Not sure how you know it's definitely DEXRON-III if you have no records.


Wait, what? I DID get records, showing, among other things, an annual trans fliter change...and per the head mechanic for the bus yard, they used Dexron III ATF in all the older buses.

I was hoping the MT643 would have a dedicated place for a trans temp sensor...but if not, yeah, it will just go somewhere in the sump. What is the maximum safe temp for a 643?

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