Author Topic: new board and rearend swap ?????  (Read 3178 times)

Offline cubsfan

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  • Posts: 6
new board and rearend swap ?????
« on: February 06, 2002, 09:57:00 PM »
hey guys iamnew to this board, but not to the net, i have 81 gmc witha 242 rearebd , i want a bigger and better rearend , which truck in the bone yard could i find something witha better gear and a five bolt lug patern , thanks for your help


chevmeister

  • Guest
something in the 70's
« Reply #1 on: February 07, 2002, 12:46:00 PM »
if you get a 70's rear diff it will have atleast a 3:07 gear ratio, they didnt make 2:42 stock in older years, you could even find a 3:73 in a older truck (73-79)
for 5 lug pattern you need one off of a 2WD, but you can simply swap axleshafts with a 6 lug pattern 12 bolt rear diff.


Offline cubsfan

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  • Posts: 6
Re: something in the 70's
« Reply #2 on: February 07, 2002, 03:31:00 PM »
so i am mistaken about the gear ratio in my truck ??? i thought that my freinds and i figure it was a 242 or something close to that  


Offline DrpdShrty

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  • Posts: 53
rear end
« Reply #3 on: April 05, 2002, 06:32:00 PM »
i had a worn out stock rear end in my 85 with the 3:08's then i put a 12 bolt in it with 3:42's.


Offline 78brown

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  • Posts: 3
Re: rear end
« Reply #4 on: June 11, 2002, 01:54:00 PM »
I have a 78 c10 with 373 gears and I want to replace them with 308 gears, do I have to change the whole wheel housing or can I just change out the ring gear and the worm gear.


Offline 84 silverado

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  • Posts: 77
gears and stuff.....
« Reply #5 on: June 11, 2002, 06:32:00 PM »
to my knowledge the lowest(numerical) gear you could get period in a truck was a 2.56. It was a rare thing to see because it even takes a different carrier in an 8.5" 10 bolt rear to use it. The carrier used with the 2.76 and 3.08's was good for a gear up to 5.13 I think. That's why I opted for a powertrax posi in my 10 bolt. I can use the same carrier and not have to do alot of guesswork shimming....... geez, I hate doing rearends and tranny work.......


Offline VileZambonie

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  • Posts: 19022
Re: gears and stuff.....
« Reply #6 on: June 11, 2002, 07:57:00 PM »
Well I had a 2.56 in my 80 c-10 stock! I hated them. The truck had a 400 SB and a TH400. I could fly down the highway but man it sure sucked for take off...

I think the perfect ratio are the 3.73's...all around. Most people seek out 3.73's from the stock 3.08's

Out of curiousity why do you want to change to the 3.08's?

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