The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - will 73 up gears work in 67-72 and visa versa

Mike C · 06-15-2002, 10:44 PM

If both rear axles are 12 bolts and if both are the same series. 3.73 and up requre a 4 series carrier in trucks and less than 3.73 is a 3 series. If you want to put 3.73 on the posi and it is 3.07 you can buy a thick gear from Richmond. That's the way my 4.10s are, mounted to the original 3.07 Eaton posi in my JImmy.

06-15-2002, 10:44 PM	#2
Mike C Registered User Join Date: Dec 1999 Location: Austin, TX, USA Posts: 7,714	If both rear axles are 12 bolts and if both are the same series. 3.73 and up requre a 4 series carrier in trucks and less than 3.73 is a 3 series. If you want to put 3.73 on the posi and it is 3.07 you can buy a thick gear from Richmond. That's the way my 4.10s are, mounted to the original 3.07 Eaton posi in my JImmy. __________________ 44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax