Rear End Gearing Opinions

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Well that's an interesting idea. I'll have to think about that. I've never loved the look of the big ones that clamp onto the spring. Are there more modern designs that aren't that expensive? Since I'm just looking to try this out, I'd hate to spend a bunch on it to experiment. 

Thanks

 
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To be honest I forgot all about the clearance on the tunnel. I apologize.  I do remember now that you mentioned it. I clearanced mine with a hammer and a long solid rod. My car does have shackles in the back and sits pretty high. So that maybe why mine didn’t rub as bad.  

 
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Each car is different, and honestly a little relieved that you had do so some of that as well. It was really bad at first. I didn't have a good angle to see it and didn't catch that there was going to be a clearance problem once the suspension is down. With the new shackles and probably 1.5" of lift, it's not hitting most of the time. I hit a big bump yesterday and it touched but at least didn't bash into the floor like it was. I had the same idea of trying to use a rod of some kind and a hammer to make some room, but haven't been able to come up with the right rod and a way to do that in the driveway. Going to see if I can get it on a lift and beat the crap out of it a bit. 

My car has giant tires on it right now (tall and wide), so being that high doesn't look terrible I think as the wheel wells are still pretty full. At the moment, just glad to be able to drive it and see how this rear end works. 

 

detritusmaximus

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Sitting stationery, how much clearance do you have? If you go to smaller wheels and shorter shackles, how much worse will it likely be?

I've considered getting an 8.8 as well for when I get around to my car. Probably a 3.55, but 3.73 is more common. 

What year Explorer did yours come from? I intended on getting one with disc brakes and from a leaf spring Explorer. 

After reading about the offset, I figured on shortening the long side so the diff was centered to avoid the 'clunk' and exhaust clearance issues. Seems like it would be easy enough when moving the spring perches around.

Also, I know aftermarket aluminum driveshafts are available for the Fox and later Mustangs. Depending on the trans, I thought about an AOD or T5, then a lighter driveshaft becomes an option, too.

 
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I'm running a 408, 5 speed (.82), 3:89's with a 27" tire. 1st gear is pretty useless. I'm running nitto 555R II's and can blow the tires away with ease at the top of 2nd. Haven't tried 3rd yet. I don't race the car but it is fun to drive around town. 

 
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Sitting stationery, how much clearance do you have? If you go to smaller wheels and shorter shackles, how much worse will it likely be?

I've considered getting an 8.8 as well for when I get around to my car. Probably a 3.55, but 3.73 is more common. 

What year Explorer did yours come from? I intended on getting one with disc brakes and from a leaf spring Explorer. 

After reading about the offset, I figured on shortening the long side so the diff was centered to avoid the 'clunk' and exhaust clearance issues. Seems like it would be easy enough when moving the spring perches around.

Also, I know aftermarket aluminum driveshafts are available for the Fox and later Mustangs. Depending on the trans, I thought about an AOD or T5, then a lighter driveshaft becomes an option, too.
I've got tons of ground clearance if that's what you are getting at. I'm not sure smaller wheels / tires would make a difference on the clearance from the rear end to the floor. Honestly I think if I had realized this would be an issue, I likely could have made enough clearance when everything was out of the car without too much trouble. I was just in too much of a hurry to look at it from different angles. My tires are comically tall at about 28.75".

Unless I'm misunderstanding what you are thinking, not sure shortening the long side would work as then the rear end would be too narrow. The whole point of using the explorer rear ends is they are the right length but have that offset. I used my existing driveshaft, so no change there. For the most part it all just goes together nicely and just needed to deal with that corner of the floor.

The rear end is out of a 2000 Explorer, 4.10 gears, LSD and disc brakes. With the gearing in my trans, it's still not too low and I do need 1st. I can start off in 2nd, but would need to slip the clutch too much. 

 

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I was thinking that if you changed to more normal sized tires at some point that it would look odd with the longer shackles ( too much space above the tire), so if they were to be changed out then you lose diff to body clearance.

It's been awhile since I was investigating the 8.8. I know some people have modified the tube lengths to get the axle the right width and the diff centered. Probably some misremembering there.

While the aluminum driveshaft is not a necessity, with an AOD/T5 and 8.8., if the ends are compatible, it is less mass to get rotating and less weight in general.

I think the T5s/TKOs have a standard 1st gear of 2.97 and an optional 3.27 (or something), more friendly to the 3.55/3.73. The TKOs have either a .80 or .63 overdrive. Sounds like the .63 would be too much of a gap.

 
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A question for you. Does your leaf springs still have the clamps around them to hold them together? If not you need them to help with spring wrap up.
Back when money was tight we use to take another main leaf spring and cut the eye off the front and cut the back off just back where the axle housing mount sits. Would add this 1/2 leaf to the front side of the springs on top of the main leaf. We would make two clamps for the front and one for the rear and really helped with wheel hop and wrap up and just used a junk spring. You can see the stock clamps in this picture.

DSC_0995.JPG

 
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The TRI-5 Chevy guys cut the axle tubes off both sides and swap tubes and axles from side to side to center the differential. It sounds a bit tricky to do but I know two guys who have done it successfully. Just a thought. Chuck

 
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Thanks. I'm well past that at this point and honestly this isn't the end of the world, just need to make a bit of clearance at one stop on the corner of the tunnel. I really wasn't in a good position to do much fab on this, so I wanted this to be as bolt on as possible. The thing with the explorer rear end is that it's the right length from the get go. So no cutting but a bit of a clearance issue to be dealt with. So this is a lot more DIY friendly for someone not looking to get new axles and what not. Basically find an Explorer rear end with the right gears, LSD and discs. Cut off the perches, fit it with new perches and weld those on. Hammer in some clearance in the corner of the tunnel and you're pretty much done. 

For someone doing this going forward, here's some of the parts I used. 

I used a longer than normal perch that's supposed to help with spring wrap. They are 7-3/4" in case the ebay ad listing goes away. 

https://www.ebay.com/itm/143192608713

I used these adapters for the parking brake. Yes, could do the typical cut the end and wrap the cable around the new location, but this was literally just pop it on and it worked. 

https://www.theflopshopoffroad.com/products/ford-8-8-swap-e-brake-cable-adapters

And while pricey, I ended up using this plate as again I didn't have a good way to do much of the fab. This plate comes with the shock tabs, U-bolts and is ready to go.  

https://www.summitracing.com/parts/cur-ce7007a

 
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