View Full Version : 9" Ford rear end

07-07-2007, 09:23 PM
What 9" rear end from what Ford will bolt directly into a '70 Javelin? Thanks

07-08-2007, 02:26 AM
if you want to put in a Ford 9" rear you will need to measure your leaf spring mounts and contact Currie Enterprises to set one up for you.you will also have to measure from axle flanges side to side to get the correct width also.i've read of guys putting in Explorer rear ends with disc brakes but i'm not sure what mods were needed.as to a direct bolt in from a Ford (like a mustang),i have never heard of a "bolt in swap".you must be new to these cars,as nothing from the "big three" is a direct bolt in when it comes to major components like engine,trans,rear.AMX Enterprises (linked to this site) does offer one piece axles for the AMC model 20 rear and gears are still available in many ratios from aftermarket suppliers.if you find one that fits,let us know as many would probably like the info as the ford rear is a strong unit.

07-08-2007, 11:13 AM
Been an AMC enthusiast for over 20 years. Bought my Javelin back in high school and still AM proud to say I own it. I heard years back that a '73 Mustangs rear end was an direct swap...I am sure that is not entirely true, but I thought someone might have picked up on this and had some insight. I hate like hell to put non_AMC parts into this car, but finding the twin grip for this car is risky at best, especially thirty seven years after the fact. Thanks for replying...you'll be seeing a lot more questions now...got some time to drive it, and want it to look and run good.

07-08-2007, 01:15 PM
try Tony @ California Classic AMC,(also linked to this site) as he might have a twin grip carrier for your car.also there are the other AMC vendors who might have one of these rears laying around too.personally i like the 9" idea as it allows more gear selections and is by far a stronger rear.add to that the stronger axles readily avaiable through Currie Enterprises and aftermarket disc brakes that are made for these giving you better all around strength and stopping power.just my opinion

07-08-2007, 03:47 PM
Hi, if you are to use a Ford 9 inch rear end you will need to have the purches moved to fit. Yes, some have claimed to have bolted on a mustang rear, but it works if you have worn out eye-bushings. If you plan on using custom wheels that fit new mustangs, a F-150 or van up to 1979 will fit. It will allow for the deep offset wheels to fit with out need of spacers. The only rear end that will bolt on directly is a 68-70 MOPAR B body rear AKA Polara, Coronet with 383 or bigger engines. Too hard to come by now, but still can be found if you snoop around. Opps! I am assuming that 70 AMX and Javelins have the same width as 71 through 74.

07-08-2007, 10:00 PM
a ford 9 inch out of a 67 thru 70 mustang and possibly a cougar(69 thru 70 for sure) will fit an amx. my 70 mach 1 is only 1/2 inch closer on the perches to the inside and that is well within tollerances and the width from drum to drum is the same. in my area and who i know the ford rearend is easier to come up with. the mopar boys want too much. and besides you can search old yards and run across posi rear sections out of trucks. the 31 spline big bearing can be turned into a 28 spline big bearing if needed but not vise versa with a factory 28 spline small bearing. 28 spline axles are the most common. the 31 spline from a mustang are the hard ones to come across and if you do find some then you might want to put them up on ebay to pay for a nice free rearend changeover. jeremy

Big Bad AMX
07-10-2007, 12:19 PM
AMC Model 20 parts from posi to lockers, axles, ring and pinon, etc, etc, are readily available through the Jeep market. Have a look: http://www.drivetrainspecialists.com/categories/amc-model-20/


section 8
12-12-2007, 04:40 PM
I have put a few rears in my 68 and i think they are the same as the 71-74 javelins. a granada 9" will bolt in directly. The only thing you need to modify is the drive shaft. It will be a 1.25 inches too long and will wipe out your trans tail.

12-07-2008, 12:58 AM
I have been told the 71-74 amx rear is wider than the 70 down. If your choice is a ford 9 inch then look for the 67-70 mustang, 69-70 cougar(maybe 67-68), granada is suppose to be an exact swap for the 67-70 mustang but will be really hard to find now, the lincoln versailes will also work and can have disc but they are expensive to rebuild. I have not measured it out but the explorers are suppose to be a disc swap for the nine inch from a car not a truck.

Truck 31 spline posi units are not that hard to find if you keep your eyes open and know what to look for. I have four of them with less than 150 bucks for all. 31 splined carriers can be converted to the mustangs 28 spline axle(180 bucks with clutch packs/shims) bearing kits/shims are 80 on up. 350 ratios are very common on 4x4's.

If your driveshaft is too long on these conversions then you can switch out the pinion side yoke also. These things are in all lengths. You have to know how to set the bearing tension but the conversion can be done with junk yard parts. Bring a cup of the u-joint with you in your junkyard adventure. Their diameters are different also.

www.badshoeproductions.com is a great web to buy videos on how to rebuild 9 inch chunks in full details with all info needed of tools and all. I just rebuilt my Mach 1's rear and it was a piece of cake.

If you don't plan on changing gears in a very short amount of time then just buy one piece axles and learn how to set up gears and find one of those china tool shops and buy you a dial indicator on vise grips and a torque wrench and have at it yourself.

When I climb back under the 70 Mach 1 to put it back together then I will measure the axle centerline to the end of the pinion yoke, outer drum(wheel mount side) to outer drum(wheel mount side), and perch center to perch center. The only part I haven't checked is the pinion length to the AMX's so far. I will post with all info.

By the time you get the other rear, fix the brakes, convert the lines, maybe new bolts to get it to mount then you will have 400 bucks in it for sure. The axles are less than that, you will have to get the bearings pressed (expensive now) on and make sure you have backing plates on there first, and are a jack away, 5 lugs, a drum, 5 bolts for the axle, maybe a good beating and maybe not, pull, and you are going back together.

Just build you a five speed while you are at it with a 2.95 first gear and bullet proofed with a positive stop shifter and say the hell with changing out my low gears.

Here is my goal for the AMX: 400 horses, five speed(need a green driven gear for speedo), 3.52 ratio with solid axles.

WWI Flying Ace
01-09-2009, 03:50 PM
Here is my goal for the AMX: 400 horses, five speed(need a green driven gear for speedo), 3.52 ratio with solid axles.

Want to do mine? I'll pay ya!