# Carrier Swap or Rear assembly swap



## AMT1379 (May 11, 2010)

My 67 has a 12 bolt donor rear with 4.10:1 r&p gears. I don't take it to the strip so it's a bad fit for me. 

Any opinions on what's most cost effective, swap out the carrier and the r&p for a 3 series carrier and and 3.55:1; or try and locate a Poncho 10 bolt 3.36:1 and get it back closer to "stockish"? I priced the carrier swap option through Randy's R&P and I'm looking at near a grand for parts alone. Still trying to find a 10 bolt 3.36:1 (or so) from a similar era car.

Both options I'd be selling the old carrier an 4.10s or selling the full 12-bolt rear assembly drum to drum.

Just for context. Trying to get my car baby home to a new house two states away. I'm in the process of moving and circumstances are forcing me to finally make this call and get the swap done ASAP. In an ideal world I would turn this 15 year driver project car into a fun family weekend cruiser, I don't anticipate ever winning a drag race or car show.


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## Koppster (Jul 27, 2008)

This might interest you:

1966 GTO 10 Bolt Posi Rear End - PY Online Forums


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## AMT1379 (May 11, 2010)

Koppster, thanks for the lead. I thought the 66 rears weren't a good fit for the 67's. I think I remember reading they were slightly shorter? I'm certainly no expert so I could be wrong on that.


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## 05GTO (Oct 6, 2004)

My 67 also had a series 3 12 bolt with 4.10:1 gears which I changed to a 3.42:1 and have been happy with the results. The R&P thru Jegs is a little over $200,

Richmond Gear GM 12-Bolt Ring & Pinion Sets - JEGS


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## AMT1379 (May 11, 2010)

I had assumed it had a 4 series, didn't realize the 3 series could also have 4.10s, I've got some more investigating to do.

If I do have the 3 series, I might be able to save a lot.


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## Icefan71 (Apr 7, 2011)

I have a 72 Lemans. I just swapped in a 66 Tempest 3.36 rearend. It is shorter than my 72. But its in place with the tires on and I can't tell the difference. There are no clearance issues. The only problem I had was I had to get coil spring retainers and exchange my new 72 springs for 66 springs. The spring pad on the rears are different.


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## geeteeohguy (Feb 2, 2008)

The '66 and earlier 8.2 rear ends are 1 inch narrower (shorter axle tubes). This will allow more tire clearance, which is a good thing.


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