Ford 9" rear end swap out-refit - axle width?

Anyone know the width of our 79 Caprice's rear axle - Axle flange to axle flange?

I am considering putting in a new custom fit Ford 9" rear end, 3.50:1 ratio.  I may also go used and put in the work to shorten one if I can't find one close to the same Caprice width...

Anyone out there with experience in this regard?

Sasmo wrote:Anyone know the width of our 79 Caprice's rear axle - Axle flange to axle flange?

I am considering putting in a new custom fit Ford 9" rear end, 3.50:1 ratio.  I may also go used and put in the work to shorten one if I can't find one close to the same Caprice width...

Anyone out there with experience in this regard?

Use a impala ss rear from 94-96
8.5" rear, 3.08 gears , rear disk brakes and posi
Grab from the driveshaft and back
Also will need new master and combination valve to make rear disk work right

So no answer on the axle width question then? I have been searching locally for the Impala SS rear end with no luck yet.

Impala rear is 59 backing plate to backing plate and that rear is just a lil bigger than the caprice
Grab a measuring tape and measure ur rear from back of drum to drum
Also b body gm rears fit caprice 9c1, delta 88, etc

For direct bolt-in rear ends, here's what RPO codes to look for in the 91-96s:

Ratio     RPO Code.                   Application
2.56          GM8                    Std. Roadmaster LT1
2.73          GU2                     Std. Caprice L99 (exc. 9C1)
2.93          GW9/GU3            Std. Caprice LT1 (exc. 9C1), Opt. Roadmaster LT1
3.08          GU4                    Std. Caprice 9C1/LT1 (Police), Std. Impala SS
3.23          GU5                     Opt. Caprice L99, Std. Caprice 9C1/L99 (Police)
3.42          GU6                     Std. 91-93 Caprice 9C1/L05, Std. 94+ Fleetwood w/V4P
3.73          GT4                     Std. 91-92 Fleetwood Brougham w/V4P

*V4P = 7,000 lb. trailer towing package... look for a hitch.

This might help too.

Chevy:

2GF / 7.625" / 2.93 (RPO GW9) ratio / 9.5" drum / 1598mm width
(soft-mount bushings)

2GG / 7.625" / 2.93 (GW9)/ 9.5" / 1598mm
(firm-mount bushings)

The remaining axles are all 8.5"

4ZB / 2.93 (GW9)/ 11" / 1566mm (taxi)

2LQ / 2.93 (GW9)/ 11" / 1598mm Limited Slip

2LU / 3.23 (GU5)/ 9.5" / 1598mm w/LS

2LT / 3.23 (GU5)/ 11" / 1566mm

2LS / same as 2LT w/LS

2GU / 3.23 (GU5)/ 11" / 1566mm w/LS (taxi)

2LY / 3.23 (GU5)/ disc / 1566mm (police)

2LZ / same as 2LY w/LS

2LW / 3.08 (GU4)/ disc / 1566mm (police)

2LX / same as 2LW w/LS

2LL / 3.08 (GU4)/ disc / 1598mm w/LS (Impala SS only)


Buick:

2GC / 2.56 (GM8)/ 11" / 1566mm

2GQ / same as 2GC w/LS

2NS / 2.93 (GW9)/ 11" / 1566mm w/LS


ALL WAGON AXLES:

2YN / 2.56 (GM8)/ 11" / 1642.5mm

2YF / 2.93 (GW9)/ 11" / 1642.5mm

2YG / same as 2YF w/LS

Thank you.  My ride is in storage for the next couple of months for the winter, so I can't find out the width my self right now. The list of rear ends are a helpful, did a search on them and the 91 Caprice police rear ends are rich in supply, maybe retired high mileage cop cars. My car guy that would be helping me with the rear end upgrade is going to try and find a pre-fabbed 9" Ford rear end for a B-body, if not, he would get a bare rear end and mount the perch and brackets himself(we'd probably be doing some suspension work to).  I just have to make the decision, my hesitation on the matter is only from what I read about, that the used GM ring gear could fail far easier than a new "bullet proof" ford. I have a week to decide before we set out to start buying parts.

The 9c1 are a good choice 8.5" axle some w/posi
Grab the control arms and its plug and play
The ford rear is good but the 8.5" is far from weak
Look toward the bottom under the pic of the camaro doing a wheelie
http://www.superchevy.com/how-to/48518-posi-10-bolt-upgrade-install/

You can still buy new 9C1 lower control arms at GM Parts Direct for something like $50 + shipping.  It comes as a complete kit with both LCAs with bushings installed and all the mounting hardware for the arms AND a sway bar.
If you're concerned about breaking a rear end it might be a better idea to use aftermarket control arms though.  There's lots of them out there.

http://www.gmpartsdirect.com
Put - 10289786 in the search box.
$45.70 for the kit.

Ooh ooh tell him bout the Southside machine shop arms less than $300 for all the arms and the hardware

HeavyChevy77 wrote:Ooh ooh tell him bout the Southside machine shop arms less than $300 for all the arms and the hardware

That's a pretty good deal.

I believe the stock 7.5s are 57ish? and the 8.5 are closer to 60(59?) from what I measured.

Can't beat a ford 9" though for durability and gear changes though. Whatever you do don't think Oem 8.8 Ford (friend

just toasted one with a straight 6cyl 4 wheeling with just under 100k.)

As far as GM rear ends, i wouldnt waste time or money in something other than a 8.5 10 bolt or the 8.875 12 bolt, both are solid rears, ofcourse the ford 9 is pretty much the holy grail of rear ends, but there are many folks running 8's and 9's with an 8.5. I just fried my 7.5 rear end earlier last year with a stock 350, and upgraded to an 8.5.

Did the op ever get the swap done