My understanding is that a Lockup 904 is actually an A998 or A999. Basically an updated 904 though. I might be wrong here, but I think 904=3 forward clutches, 998=4, 999=5
Gear ratios are the same, 2.74:1 First, 1.54:1 Second, 1:1 Third, 2.21:1 Reverse and if an O/D version, 0.69:1
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