66 12 bolt 308 posi gear change [Archive] - Chevelle Tech

: 66 12 bolt 308 posi gear change


joespc37
Jan 16th, 09, 12:05 AM
hi guys heres what i have and i dont know much about these so please chime in lol a 1966 12 bolt posi with 308 gears i pulled rearend out of a 1970 ss elike so i was surpried about the year of rearend but i guess same thing except 1 inch shorter well i put it in a 68 chevelle i am building 68 402 car and i want to change gears in this to a 373 gearing can anyone tell me what i need and how hard it is to do best place for parts thanks for any help joe

Hot66ss
Jan 16th, 09, 2:42 AM
hi guys heres what i have and i dont know much about these so please chime in lol a 1966 12 bolt posi with 308 gears i pulled rearend out of a 1970 ss elike so i was surpried about the year of rearend but i guess same thing except 1 inch shorter well i put it in a 68 chevelle i am building 68 402 car and i want to change gears in this to a 373 gearing can anyone tell me what i need and how hard it is to do best place for parts thanks for any help joe



If you have never done it before I would suggest paying someone to do the labor for you, maybe see if you can get someone to teach you so next time around you can do it yourself!

As far as the parts go I would recommend going with a high quality gear such as Motive (Made in Italy) or US Gear (made in the USA) you will need a good quality install kit and I suggest getting a "Master kit" and changing out all the small hard parts as long as you have the rear end apart. Timken and Koyo make a good product. As far as pricing goes give me a call (or PM) I can help you with whatever you decide and get you the best possible pricing.

Happy motoring,

Tom

big gear head
Jan 16th, 09, 8:59 AM
Contact Tom's Differentials www.tomsdifferentials for parts. He has the best installation kits and USA made parts.

You will need to know how to set the pinion depth, bearing preload and backlash. You must know how to read the contact pattern so that you will know what adjustments need to be made to the pinion depth. The tolerance on pinion depth and backlash are +/- .001 inch, so this is a precision job. It requires MUCH patients. You must be willing to assemble and disassemble the rear end several times to get it right.

Hot66ss
Jan 16th, 09, 6:50 PM
Contact Tom's Differentials www.tomsdifferentials for parts. He has the best installation kits and USA made parts.

You will need to know how to set the pinion depth, bearing preload and backlash. You must know how to read the contact pattern so that you will know what adjustments need to be made to the pinion depth. The tolerance on pinion depth and backlash are +/- .001 inch, so this is a precision job. It requires MUCH patients. You must be willing to assemble and disassemble the rear end several times to get it right.

Hey Freddie,

Do you know who's install kit Tom's uses? I bet its probably a timken kit and the gears he uses are US Gear, posi's are eaton. I am a Tom's fan he does great work and sells great parts.

karl
Jan 16th, 09, 9:51 PM
be careful if you use diff works in corona ca. they have a nice office up front but out back unorganized. they never returned my shock bolts, diff cover bolts, cover gasket or bumpstops. these parts arent cheap to replace.

big gear head
Jan 16th, 09, 11:44 PM
I think Tom uses Dewco kits. They have Timken berings and the original Super Shim set. DTS uses the same kits. There are some coppies of the super shims that are not quite as good. Yukon is one of them.