Author Topic: 9 inch rear  (Read 2048 times)

tblackgt350

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9 inch rear
« on: August 08, 2019, 09:46:00 PM »
 I think I am about to rebuild my cars rear stump and change from 3.89 to a 3.50; If I already have the ring and pinion, do you have any idea what this should cost?
Thanks

GT350Lad

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Re: 9 inch rear
« Reply #1 on: August 08, 2019, 09:57:14 PM »
Not sure on cost, but why the change? Curious
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Greg

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Re: 9 inch rear
« Reply #2 on: August 08, 2019, 10:01:14 PM »
Assuming you are trying for a lower RPM, going from 3:89 to 3:50 you won't even notice the difference.  That would be a waste of your time and money IMO. 
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gt350hr

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Re: 9 inch rear
« Reply #3 on: August 09, 2019, 10:22:10 AM »
  The change is around 300 rpm at highway speed. Cost can be over $150 depending on the person doing it.
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6s1640

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Re: 9 inch rear
« Reply #4 on: August 09, 2019, 12:25:33 PM »
Are you doing all new bearings?  Will you supply them?  IIRC, TIMKEN is the original supplier.  Try to find US Made versions.  They are still available but you might have to work at it.  You will need new pinion seal , crush ring and new nut.  Will you supply those as well?     Everything will need to be re shimmed as well.  It could be a couple of $100.

I ran a car to SAAC 35, 2000 mile round trip.  I swapped out the 3:89's and put in 3:00's.  It sure made driving the interstate nice.  They are still in the car.  If you are not turning 6K, burning rubber  and drag racing, the 3:00 gears are faster off the line and are little more fun driving around.

Best of luck

Cory

1967 eight barrel

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Re: 9 inch rear
« Reply #5 on: August 19, 2019, 02:15:20 PM »
The last one I had done was 225.00 in labor.  I provided all parts but the seals and shims. I also provided the clutch pack for the limited slip carrier.

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tblackgt350

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Re: 9 inch rear
« Reply #6 on: August 21, 2019, 11:24:03 PM »
 Sorry I didn't reply earlier; I got really busy and then went to Carmel for car week. I was going to go through the rearend because there was a little bit of a whine when getting out of the throttle; it appears this was just a loose pinion nut. I already had a new 3.50 set and thought if doing a rebuild it might a few rpm when cruising.

1967 eight barrel

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Re: 9 inch rear
« Reply #7 on: August 23, 2019, 05:01:55 AM »
I have 3.50's with 25.25" tall tires. My cruise speed is about 3050 at 65. I am changing to 3.07 with a wide ratio four speed.
 
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