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When doing a drain and fill....

844 views 6 replies 3 participants last post by  maxpower29 
#1 ·
I just bought a used 2003 dually with an 8.1 and allison transmission. I want to swap the fluid over to Transynd. If I change the filter and add the 7.4 qm but what is the current fluid is just the old stuff from the dealer? The truck is 13 years old but only has 89k miles on it so I do not know if it was ever changed or what was used in it if it was changed. Thanks
 
#2 ·
Factory fill was Dexron 3 but any brand Allison TES 295 spec fluid will also work.
 
#4 ·
Yes they can be mixed.
 
#5 ·
Change the spin on filter and then do it again in 5000 + miles and they say thats pretty much a complete change to synthetic , expensive but worth it. Madjack diesel has a good price on Transynd
 
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