Guys, I have been working on this, and I think it may be pretty hot news for us. It looks like Ford Explorer, Mercury Mountaineer, and Mazda Navajo axles might be some really good cheap axles that we could use. Explorers come with 3.73 and 4.10 gears and it is not uncommon to find them with posi. They all have 31 spline axles, so this puts them very close to the best 9 inch rears in strength. The later axles (95 on up) with disc brakes measure 59 and 3/4 inches, so that would work with some newer deep backspace wheels. I need to measure a drum brake earlier axle. I have every reason to believe it is a couple inches narrower and would work perfectly with my Magnum wheels.(When Mustangs went to rear disks around '94, the axles got 2-3 inches wider) It looks like the only change needed might be the spring pads. They are on the correct bottom side of the axle, but too close together, from some rough details that I have currently. But these need verification. Anyone have one of the vehicles above that they can measure? Along the way in researching this too, I found out that another source for 8.8 rears, many with posi, are ... ...are you ready for this ... ... I wasn't ... Volvos! ... really! ... Volvos! You just want to get a 1987 or newer one to get the Ford bolt pattern, from what I was reading elsewhere. Earlier ones had a metric pattern. I know nothing about Volvos, but I suspect that these are four link/coil suspensions. Also there were no measurements given, but they may be very close to our cars. The research continues ...
The offset chunk, combined with spring pads, and narrowing make this more expensive than just grafting a 9" housing center into your 8" rear, ala Carol Shelby... Costs about $200 bux locally here for the cut/weld of the 8" tubes onto a 9" center. Use your stock 28 spline axles with a 9" 28 spline chunk and you're done. No custom axles, no spring pad or spring mount bolt changes, no brake changes (unless you just want to do the CV disc swap), and no driveshaft shorten. You already got the 8" donor rear, and the 9" donor for this swap can be the absolute most undesirable empty housing you can find. Many can be had for free or scrap price. I got a guy trying to give me a coil spring Torino 9" right now. He wants it out of his yard. Just a thought. Dave I also should mention the 8.8" rear is heavier than a basic 9" rear.
You might also want to check out this thread: http://mmb.maverick.to/showthread.php?t=35505&highlight=8.8
explorer rear axle Good info guys. Thanks for the links. One thought ... an offset chunk does not need to be centered as long as the driveshaft clears the floorpan, etc. U-joints need a bit of offset, whether it is side-to-side, or up and down. If you were doing a car from scratch and had the centerline of the crank aimed right at the pinion, the driveshaft would have a vibration problem. Mopars used to move their engines over an inch for this reason as well as to clear the steering better. Cars with a centered chunk will have the engine mounted higher or lower than the pinion snout for the required offset. As pointed out in one of the links, you will need to make the pinion angle oppose the angle of the tranny. Still looking for a measurement on an earlier drum brake Explorer rear axle if anyone has one. I'm betting darned close to 57 inches ...
we bought an explorer rear out of a 2000 expl sport 2d 2wd and the chunk is not offset Almost have it installed
btw, this one is 59.75" we are using 17" cobra R wheels from a 99 to put the wheels back in place will have to put 3/4" spacers on front axle to clear springs...the rear will set just inside the fender wells. moving front spring hanger to underneith the frame and 1" to the rear found a conversion u-joint at oreilly auto to mate flange yoke to stock drive shaft
