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Dead Parrot · 06-11-2017, 05:36 PM

Can't answer for the number decoding but a 3.40(aka 3.42) isn't an oddball. My 75 has that in a 12 bolt. Option code HE4 - 3.40 ratio, on my truck's option list.

Just spin the yoke and count the axle rotations.

06-11-2017, 05:36 PM	#4
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,496	Re: 12-bolt gear ratio ID. Help needed! Can't answer for the number decoding but a 3.40(aka 3.42) isn't an oddball. My 75 has that in a 12 bolt. Option code HE4 - 3.40 ratio, on my truck's option list. Just spin the yoke and count the axle rotations.