In practice they seem to vary wildly. 3.23 is rare, most of the serII mpfi manuals I see have 3.08 or 2.92.
I've seen cfi manuals with 2.77, 2.92. and 3.08.
Our serI auto CFI got a 3.08 diff.
I think it was all optioning really, most of these cars they never changed the oil let alone the diff
You will have to crawl under it and look.
Proud TQE Operator and President of SEFAG - the Society for the Elimination of Ford Automatic Gearboxes
Pacemaker headers + 2.5" exhaust
EF Fairmont interior
Lowered King springs
5 speed manual
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