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Currie 1964-66 Mustang 9 Inch Replacement Rear Axle

Currie 1964-66 Mustang 9 Inch Replacement Rear Axle

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Q & A

What's in the Box

Now you can have all the strength and serviceability benefits that the Ford 9" offers underneath your Mustang. Currie Crate Rearends are built using the stock overall width, pinion offest, and mounting points of your original rear axle housing, making it a 100% bolt-in upgrade (with the addition of new U-bolts and spring plates designed for a 3" O.D. axle tube).

  • All new 9-Plus heavy duty housing
  • Heavy duty 2-1/4” wide leaf spring pads installed in stock location
  • 31 spline performance axle shafts
  • 57-3/8" width
  • Torino-style late model large bearing housing ends
  • Third member studs installed
  • Axles drilled for stock 5 on 4-1/2" wheel bolt pattern
  • 1/2"-20 wheel studs pressed into axles
  • 1/4” thick heavy duty bearing retainer plates
  • Tapered Timken style wheel bearings pressed onto axle

Note: Works with Speedway rear disc brake kits, 11" Ford Explorer disc brakes, and Wilwood disc brakes. Third member sold separately. Requires axle U-bolts and spring plates designed for a 3" O.D. axle housing tube (not included).

How to Measure Your Housing Tech Tip (Link)

To learn more about Currie's 9+ rearends, check out these Frequently Asked Questions on 9-Plus Housing (Link) 

Need a certain length not found on our site?  Check out Currie's 9+ Rearend Calculator to have specially sized axles or rearend housings made for your specific application.  Custom orders will be built and processed directly through Currie Enterprizes and shipped to your door. For ease of ordering, please refer to Currie's Dimension Diagram

Installation Notes:

When installing new axles in rearends with posi traction differentials, be sure to install the driver's side axle first to keep the splines properly aligned.  Failure to do so may move the two splined gears out of alignment, and it may be difficult to install the driver's side axle properly if the passenger side axle is already installed.

If installation of passenger side axle is done first it may require two people when installing the driver's side axle, with both parties rotating reach axle until splines are in line and the driver's side axle fully sides into the housing.

To ensure you get the most out of your new 9 Inch components, Currie recommends that you perform a proper break-in process:

  • Use a name brand mineral-based gear oil, preferably 85w140 (Extremely high quality synthetic oils may be used once break-in process has been successfully performed)
  • Place vehicle on jack stands and let the rearend spin while the vehicle idles - run transmission in both forward and reverse periodically throughout the process
  • Continue to run the rearend until the pinion gets hot (place hand on bottom of the differential housing to verify this)
  • Proper break-in allows:
    • The ability to install new axles and hit the track the same day without worry
    • Extended life for rearend components
    • Keeps the quality and life of your gear oil

Note: If you find that your rearend is running somewhat "tight" be sure to add Currie's 9+ Friction Modifier to "loosen up".  If a more aggressive performance is desired, Friction Modifier is not needed.


Customer Reviews

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Product Q&A

1 questions : 1 answers

1 answers

will my 65 mustang have the same wheel base? tires wont stick out of fenders? will the tires stay tucked in the fenders, or will they stick out. same length as the oe 65 mustang dif?

Palmdale, CA, USA
December 05, 2013

will my 65 mustang have the same wheel base? tires wont stick out of fenders? will the tires stay tucked in the fenders, or will they stick out. same length as the oe 65 mustang dif?


December 05, 2013
This rear end is the same width as the stock rear end of a '64 to '66 Mustang. You shouldn't notice any difference in wheelbase or track width if replacing the original rear end from your Mustang.
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