Differential swap question
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Differential swap question
I am currently in ownership of a Ford 8.8 rear diff, with a 3.08 ratio (Axle Code 18). Being only 2 wheel drive makes the winters "fun", but I'd like to get myself a limited slip diff to enhance my traction some in the white stuff. I'm going to hit the local jy to search and I was wondering if there was any differential that would be a direct swap for mine? Could I be that lucky?
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From: Marlborough, CT
If you are looking to swap just the carriers, second generation Explorers use the 8.8 rear, and a high percentage of the AWD versions used limited slip. You'll most likely have to swap ring and pinions as the ratios might be a bit steeper, 3.55 and 3.73 most common. ~Bill
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From: Lost
80 thru 82 F100/150 all used a 9", and some 83-87 did too. As such, a complete axle assembly from one of these would be a direct fit swap, though you *may* need to get the driveshaft too. Finding an LS equipped axle assembly at a jy is doable, just have to search. Both the 9" and 8.8" axles were offered with LS options.
In reality, any rear axle assembly from 80-96 would fit, whether the donor was 2wd or 4wd. Just be aware that some 80-83 F100 trucks had a smaller bolt pattern for the wheels. You should avoid trying to swap in an axle from one of those, as it's a pain to convert the bolt pattern, or have to carry 2 different spare tires.......
In reality, any rear axle assembly from 80-96 would fit, whether the donor was 2wd or 4wd. Just be aware that some 80-83 F100 trucks had a smaller bolt pattern for the wheels. You should avoid trying to swap in an axle from one of those, as it's a pain to convert the bolt pattern, or have to carry 2 different spare tires.......
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From: Lost
However, the center section from others can be fitted into your housing, as long as the donor uses the same 31 spline axles. Just swap your ring gear over, and set the shims up to acheive the correct gear engagement.
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Bronco/F150 only. The others are usually narrower, both overall and where the springs sit.
However, the center section from others can be fitted into your housing, as long as the donor uses the same 31 spline axles. Just swap your ring gear over, and set the shims up to acheive the correct gear engagement.
However, the center section from others can be fitted into your housing, as long as the donor uses the same 31 spline axles. Just swap your ring gear over, and set the shims up to acheive the correct gear engagement.
I'm going to repeat this in my words so I can make sure I understand this perfectly. If I find an F-150 or a Bronco with and LS 8.8, it would be as simple as just swapping the axles? Meaning no dealing with the drive shaft or any of that? Would a 9 swap entail changing the drive shaft? Sorry for all the questions, there's a reason for my handle on here. I appreciate all the help.
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From: Lost
I'm going to repeat this in my words so I can make sure I understand this perfectly. If I find an F-150 or a Bronco with and LS 8.8, it would be as simple as just swapping the axles? Meaning no dealing with the drive shaft or any of that? Would a 9 swap entail changing the drive shaft? Sorry for all the questions, there's a reason for my handle on here. I appreciate all the help.
A 9" swap should also be a direct fit swap, although the pinion flange *could* be different. I do not know if the pinion flange from an 8.8" will fit a 9", as such, it is *possible* that the driveshaft could need attention, if the flange is not the same style as you have currently. There were several different 8.8" pinion flanges used over the years. Some were like the ones used on the 9", some weren't. You would have to compare what you have now, with what is on the donor.
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Post Fiend
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From: Dryden, ON, Canada
A 9" will require a driveshaft swap. I know I had to change it when I put an 84 8.8 in my 82 temporarily many years ago. I can't tell you if it was shorter or longer though.
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In my experience, any factory LS rearend you find now is going to be wore out. You can check it before you buy. Jack up one side and try to turn it while the other side is locked. You can get someone to hold the other wheel while you try to turn the other one. The resistance you feel will be how much slip will be allowed, and most of them do not have much resistance anymore.
I personally do not like a limited or locked rearend in the snow myself. Every one I have ever had tried to throw me in the ditch. With a regular rearend I just sit there and spin, sometimes making slow progress. Or I can at least back up and try again. With the limited slip, once I started spinning the rear of the vehicle went to the ditch, either one side of the road or the other.
I personally do not like a limited or locked rearend in the snow myself. Every one I have ever had tried to throw me in the ditch. With a regular rearend I just sit there and spin, sometimes making slow progress. Or I can at least back up and try again. With the limited slip, once I started spinning the rear of the vehicle went to the ditch, either one side of the road or the other.
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From: Roseville, MN
I personally do not like a limited or locked rearend in the snow myself. Every one I have ever had tried to throw me in the ditch. With a regular rearend I just sit there and spin, sometimes making slow progress. Or I can at least back up and try again. With the limited slip, once I started spinning the rear of the vehicle went to the ditch, either one side of the road or the other.
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Just got back from the jy. No bullnoses today, but I've got a few questions. Do the axle codes from 1987-96 match up with the 80-86 axle codes? And are they of the same width? If so I've found a few potential donors.
As for whether the limited slip will help or not, after this past winter that we experienced in Maryland, I'm really willing to try anything. I don't plan on doing much driving in the snow, but if I have to, I'd like to know I'm getting home, unlike some attempts this past year. I'll keep my old axle just in case I have the same findings as you all. I do appreciate the tips, because I probably would have scrapped the old axle after the swap
As for whether the limited slip will help or not, after this past winter that we experienced in Maryland, I'm really willing to try anything. I don't plan on doing much driving in the snow, but if I have to, I'd like to know I'm getting home, unlike some attempts this past year. I'll keep my old axle just in case I have the same findings as you all. I do appreciate the tips, because I probably would have scrapped the old axle after the swap
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From: Virginia
Limited slip and / or lockers definitely hurt stability in snow or on ice. But they do help you move forward. A lot of people don't like it. Personally I don't mind having a locker (usually hurts stability / helps traction better than a limited slip) in the rear, but then again, I've got 4WD and that helps with both. I'm not sure what I'd want in a 2WD.
Up to 96 should bolt right in. Finding the correct ratio is going to be tricky though, to match the front. 3.08 is good for fuel mileage, but not so much if you have oversize tires or tow with it.
3.08 was a door jamb code H8 in the early years and the later ones also. There is also a code 18, code 32, and code 41. I think I am right in saying the codes with letters are limited slip, just numbers are regular open rearends.
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From: Lost
I wouldn't rely on the door tag. Axles can be changed. I would crawl under the truck, and check the tag on the axle. If the tag indicates it's an LS, pop off the cover to make sure and inspect the gears. A few extra minutes at the yard, can save hours of work swapping in another axle to replace a bad one that came from the jy.
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From: Roseville, MN
And mostly I was agreeing with you that limited slip makes a 2WD squirrely. I drove my '95 F-150 SCSB with a rear locker in 2WD almost all of the time (I could never get rid of a vibration in the front driveline in that truck...). So I lived with it a lot. But I always did have 4WD to fall back on when it started getting bad. And 4WD does make a rear locker a LOT less squirrely.
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Met a guy at the yard who has a '92 8.8 with 3.08 gears (which matches mine) with limited slip. He's going to junk the truck, so he'll give me the axle for $100. That seems to be a good deal for me, right? Unless that seems outrageous to any of y'all, I think I'm going to pull the trigger and see what happens.