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Mountain Man · 05-23-2002, 05:10 PM

I need to swap the factory 4.57 posi out of my 67 1/2 ton. I am reving 4,000 at 60mph!

I am thinking of going with 3.42 auburn posi diff. What do you guys think of this set up.

I have a TH350 tranny, my tire size is a 255/60/15 and measures about 26" in height. What kind of rpm would I be turning with the 3.42 at 60mph.

Thanks for the opinions, in advance.

05-23-2002, 05:10 PM	#1
Mountain Man Registered User Join Date: Jan 2002 Location: Calgary, Alberta, Canada Posts: 451	Need opinions on differential brands/ratios I need to swap the factory 4.57 posi out of my 67 1/2 ton. I am reving 4,000 at 60mph! I am thinking of going with 3.42 auburn posi diff. What do you guys think of this set up. I have a TH350 tranny, my tire size is a 255/60/15 and measures about 26" in height. What kind of rpm would I be turning with the 3.42 at 60mph. Thanks for the opinions, in advance. __________________ 72 C10 Cheyenne Super Full trim Factory tach dash A/C dash Factory tilt 350 / 350 power train - with Edelbrock components.