Rear end (suspension and wheels)

I'm currently in search of a Ford 9 inch to put under my rusted out 1973 Mach 1. I found a couple of rear ends locally one is a late 70s f100 rear end that is 65" and wrong lug pattern.  The other is a Ranchero rear end that is 63" with 28 spline axles with 5x4.5 lug pattern.  The truck rear end seems like a lot of work to narrow and find conversion bearings for my 8" axles.  The Ranchero rear has the right lug pattern but is 1.75" longer.  I'm wondering if I can  just weld on spring perches on the Ranchero  rear end and get rims with larger backspacing.  Im trying to convert to a 9" rear end and set it up for drag racing on a tight budget.

28 spline axles are probably weaker than the 8" rear center section. Cobbling together the ranchero rear doesn't make sense.

Speedway sells 9" bare housings in various widths for 399.00; a decent built center section can be had for about 800.00 and quality axles will cost about 250-300 for the pair.

or you could go pick up a 8.8 out of an explorer for 250 bucks at the bone yard, with disc brakes and it is the right width and the right pattern and they are strong enough for all but the stoutest of engines. Many are posi and 3.73 gears

28 spline axles are probably weaker than the 8" rear center section.  Cobbling together the ranchero rear doesn't make sense.

Speedway sells 9" bare housings in various widths for 399.00; a decent built center section can be had for about 800.00 and quality axles will cost about 250-300 for the pair.

or you could go pick up a 8.8 out of an explorer for 250 bucks at the bone yard, with disc brakes and it is the right width and the right pattern and they are strong enough for all but the stoutest of engines.  Many are posi and 3.73 gears

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+1 with what jeff said about the 8.8 inch.  They are also 31 spline. I have been running one in my Mach 1 for several years with 0 problems. Here's a link to some good info on the 8.8 http://www.therangerstation.com/tech_library/Explorer8_8.shtml

What did you guys do about the offset rear end of the explorer? I have wanted to do a narrowed explorer rear end in a early Falcon but haven't found the right shell.

I didn't do anything about it. It's offset but not enough to interfere with anything and I have no driveline angle issues. I have probably been running it 8-9 years with no issues.

I didn't do anything about it. It's offset but not enough to interfere with anything and I have no driveline angle issues.  I have probably been running it 8-9 years with no issues.

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I have more questions about the swap.  Did you do a build thread?  What did you do about the shorter rear axle?  Did you run a shorter backspacing?  Also did you get the explorer driveshaft and have a custom driveshaft made?  I'm running an explorer gt40p motor and a built AOD with a 3k stall converter.  I want to eventually turbo charge it and put wide tires or slicks.  I just went to Roadkill Zip Tie Drags, and they had a hooptie challenge for car worth under 3k.  The guy that one had a Chinese turbo 5.3.

I really need to figure out what I'm doing for a rear end because I just swapped the motor and trans only to find out the trans was longer.  Now I need to shorten the drive shaft and I'm not paying to do it again when I upgrade the rear end.

If you wan t a bare used 71-73 mustang rear axle for a decent price plus shipping..... http://www2.cougarpartscatalog.com/d1zz-4010-b.html?attribs=86

I didn't do anything about it. It's offset but not enough to interfere with anything and I have no driveline angle issues.  I have probably been running it 8-9 years with no issues.

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I have more questions about the swap.  Did you do a build thread?  What did you do about the shorter rear axle?  Did you run a shorter backspacing?  Also did you get the explorer driveshaft and have a custom driveshaft made?  I'm running an explorer gt40p motor and a built AOD with a 3k stall converter.  I want to eventually turbo charge it and put wide tires or slicks.  I just went to Roadkill Zip Tie Drags, and they had a hooptie challenge for car worth under 3k.  The guy that one had a Chinese turbo 5.3.

I really need to figure out what I'm doing for a rear end because I just swapped the motor and trans only to find out the trans was longer.  Now I need to shorten the drive shaft and I'm not paying to do it again when I upgrade the rear end.

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Unfortunately, I did not do a build thread. I did this swap before I was a member on here. I did end up just ordering rims in the back spacing that best fit the rear end. I cant remember off hand the back spacing, but once you have it in, you can measure up to order your rims.  The 8.8 isn't a bad swap. Pretty easy if you have some fab skills and a welder. The width are pretty close to each other if you get one from an explorer. You will need to cut off the leaf spring perches and shock mounts from the 8.8 and toss them. I bought a new set of perches from summit. You will need an angle finder to get the pinion angle of your old rearend. Once you have that you can tack the new spring perches on the 8.8 on the same pinion angle and in the same relative spots as the old rear end. Make sure you pull a measurement from backing plate to backing plate to get center then measure over from that to set your perches. Don't go by the center of the pinion. The center of the pinion is offset to one side slightly on the explorer rearends. I never had any trouble with this and never had a vibration at high speed.

The shock mounts you will need to fabricate new ones. I used my old u-bolt plates and cut the shock mount ears off and welded them to a new piece of 1/4" flat plate with new holes drilled for the new u bolts. You cant use your old plates or u bolts because the 8.8 housing is bigger in diameter. I had the driveshaft shop make me custom u bolts for about $35. You will also have to have your driveshaft shortened just a touch if I remember right. I had the end of the explorer driveshaft weld on the end of my original drive shaft so I didn't have to mix and match to get the right u joint. Now all I need is a stock 71 mustang u joint up front and a 2005 explorer ujoint in the back. Brake lines are pretty straight forward. And I even was able to use my ebrake cable and just fabricated a new arm for the 8.8 rear.

If you have any questions let me know. I can walk you through it. Its pretty simple and a great upgrade. You get 31 spline axles, posi, 3.73 gears, and disc brakes all in one shot for Probably $500 or less in all materials including the axle. Also don't forget to weld the axle tubes to the center section all the way around. The factory only pressed the axle tubes in and they are prone to twisting there if not welded. I have been running close to 600hp through it for the past 3-4 years and about 425 hp through it for 4-5 years before that. It has never missed a beat.

I believe 94-98 Mustangs also have 8.8" rear ends with 31 spline axles, and I believe that the wheel flange to wheel flange width may be very close to the 61.25" width of our 71-73s. I haven't been able to firmly verify the width, though, but believe they are 61.125". In '99 the axles went about 1.5" wider.

An interesting thing about the 8.8" rear ends, they have a larger diameter pinion shaft than the 9" rears. That, along with 31 spline axles actually make them stronger than the 28 spline axles in our cars.

I believe 94-98 Mustangs also have 8.8" rear ends with 31 spline axles, and I believe that the wheel flange to wheel flange width may be very close to the 61.25" width of our 71-73s. I haven't been able to firmly verify the width, though, but believe they are 61.125". In '99 the axles went about 1.5" wider.

An interesting thing about the 8.8" rear ends, they have a larger diameter pinion shaft than the 9" rears. That, along with 31 spline axles actually make them stronger than the 28 spline axles in our cars.

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Don, from the research I did in the past all the mustangs from 79-04 came with 28 spline axles regardless of the rear end. In 05-10 the 8.8 in the mustangs had 31 spline.

That's possible, there's a lot of conflicting information out there about them, including widths. The article I got the information from should be reliable, but I wouldn't wager any money on it.

Yeah I'm not 100% sure either.  But this is one of the articles I found. https://lmr.com/products/Mustang-7-5-8-8-Rear-End-Axle-Info    And everyone knows if I read it on the internet, it HAS to be true!!!! rofl ::thumb::

Common 9" Ford axle widths

• 65-66 Mustang 57.25 inches
  
• 67-70 Mustang 59.25 inches
  
• 71-73 Mustang 61.25 inches
  
• 77-81 Versailles 58.50 inches
  
• 74 Maverick 8" 56.50 inches
  
• 75 Mustang II 8" 57.00 inches
  
• 67-73 Mustang, Torino, Ranchero, Fairlane 9" 59.25 inches to 61.25 inches
  
• 57-59 Ranchero and Wagon 57.25 inches (narrowest 9" housing)
  
• 66-77 Bronco 9", 58 inches (has 5-on-5 1/2 inch diameter bolt circle)
  
• 77-81 Granada/Versailles, 58 inches
  
• 67-71 Comet, Cougar, Mustang, Fairlane, 59.25 inches
  
• 64 Falcon 58 inches
  
• 67 Cougar 60 inches
  
• 67 Fairlane 63.50 inches (coil springs)
  
• 72 Ford Van 3/4 ton 68 inches
  
• 67-73 Torino, Ranchero, Fairlane 59.25 inches or 61.25 inches
  
• 67-71 Comets, Cougars, Fairlanes 59.25 inches
  

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