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This being So. Cal. desert season and figuring to check out the main Jeep/4x4 event in March, I caught up on a few of the next mods I wanted to do on our daily-driver '91 Cherokee. The ol' black box sits just a tiny bit too low in front, it needed more height but not enough to put front-end geometry out of whack. In the course of building something else I had come up with a pair of front spring spacers that could be installed without removing the coils as it's a bugger to get those drawn down over bump-stop columns inside. As you'd figure, these just clamp in from the sides. They're only an inch in height gain but that will do.
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At the rear, one of the things that has been a problem is needing a tie-down and jacking points. Cherokees just don't have a good place back there. Up 'til now we've had to hook around the rear axle which risks brake line damage plus I don't much care for crawling around underneath the car to lift it when out in the dirt or rocks. 1/4" steel brackets mount behind the bumper, connect to channels that attach under the frame rails (if you could call them that) such as a trailer hitch would, and clevis shackles from the hardware store hang below. They can swing free up to 90* where they stop and let a high-lift jack catch in. You can barely see on the left, while I was at it I pulled the rear springs apart and added a second main leaf for a tiny bit more lift. They curve around the bottom of the originals to make a semi-"military wrap" to reduce the likelihood of breakage there. Leaf springs do break and when they do you're screwed.
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We've had an OK combination of traction and streetability with a Ford Racing posi unit in the rear 8.8, but the front Dana 44 has been open and helped get us stuck a couple of times when one front wheel lost it and wound up just spinning in the air. I had originally wanted what they call a "lunchbox locker" in there, not wishing for the expense and hassle of a selectable, and finally pulled the trigger. I had a bad time trying to research these units, even the supposed off-road experts in their remarks about how these things work only tell you what they do...not how they work. Yeah we know what they do, that's why we'd get one, but understanding operation would help somebody to choose among the three-or-so most common brands. Anyhow, they are comparable to a clutch-type posi if you could imagine you were using the posi clutches only to drive the vehicle and not spider gears, except: Instead of clutch packs on each side there are positive locking splines which can engage/disengage, and instead of side force for that being applied by outward pushing of side gears by spiders, the notches that the big center pin fit through to transfer torque are angled to create side thrust, i.e. input torque causes outward movement of the center "drivers" and engagement into the driven sides which connect to the axles. For one side to disengage around a corner; when pushed along by the outside wheel rather than being driven, half of the driver set can rotate forward a few degrees relative to the other on it's angled pin ramp and release the force on that side, letting things back out enough for free spinning. Small pins with springs under them that come out of a hole on one side and slide around against a flat spot on the other provide pre-load, similar to the spring on a clutch posi. Better pics of all this would help, I know, but I didn't think of grabbing the camera until this point.
What are the big flat spots on the center drivers for? That's just so they can fit into the case...otherwise, they wouldn't go through the hole.
I wound up choosing a locker branded "Spartan". Fits in the stock case like they all are supposed to, looked about like the others, got decent reviews, and I was happy to see when opening the box that everything looked very well made. Seems a little water has been getting in the old diff oil, you can see the cloudy color....since no oil has been leaking out I imagine the seals are still good. The hose on the top case vent had broken away at some point and could have been letting water in there so I guess that's what that was about.
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On a hillside overlooking a few thousand fellow campers, out for the annual "Tierra Del Sol" off-road meet last weekend. Normally that kind of stuff is too crowded and dusty for me but once a year is OK. We are camped well on the outskirts in the foothills to the right of photo.
.
We cruised around a bit to check out all the goings-on then...OK let's try that front locker now. This is some pretty soft dirt with a few rocks in it to climb up:
Gets pretty tight in there. A wider vehicle wouldn't have fit, there are a few such places in the Anza-Borrego desert Badlands which is why I've chosen to keep the Cherokee narrow instead of using wider axles/wheel offsets etc. which might be appropriate for other-type offroad areas.
Soft uneven terrain? No problem now, every time a front wheel started to slip the other one took over and pulled us right through. Now we're having fun!
And up over the top. Wonder what that flag on the back of the car is for? That's so somebody coming the other way can see you before flying over the top of the hill and having a head-on collision which is not a totally unusual event. Required safety stuff, much of the time.
.
What about that locker in normal operation? Is it clunky, does it jerk around a bit/not disengage when it's supposed to, and cause a little steering weirdness? Yes, to all that, to a degree. I don't think I'd use one in the rear of a street vehicle. Up front, when you're not in four-wheel mode the downsides are never noticed.
The Chero on the right is what I originally envisioned building but we've gone different in a few ways. Start with front overhang...believe-it-or-not, that front license plate on our car on the left would only have a few more hours to be straight and undented before I'd be smacking it into a hillside while going up something. (edit: attempting to go up something.) As far back as it is with the bumper style and the front wheelbase pushed out a couple inches, we still catch on things sometimes, with any more crap hanging off the front we'd never have a chance at some of the terrain in our part of the land. You can't see steering shaft/panhard rod angles on ours but with the box lowered and the tie rod points raised we're much closer to level for better road manners, the guy on the right has the more-common but freaky handling offset. Sticking with "small" 32" tires means the spare can go inside and not be on the roof helping to tip the car over, or be out back blocking the view.
Hey look, a carpeted car with a dog on it. The little Isuzu or whatever it is didn't go far without having a tow strap and helper attached to the front.
It's hard to see in this pic but there's a big rock and a puddle of oil under this guy's front diff. He would come out on a tow strap too.
A fun couple of days then off to home. Cheap old truck, cheap old camper, low-budget Jeep that just has some time and effort into it.
At the rear, one of the things that has been a problem is needing a tie-down and jacking points. Cherokees just don't have a good place back there. Up 'til now we've had to hook around the rear axle which risks brake line damage plus I don't much care for crawling around underneath the car to lift it when out in the dirt or rocks. 1/4" steel brackets mount behind the bumper, connect to channels that attach under the frame rails (if you could call them that) such as a trailer hitch would, and clevis shackles from the hardware store hang below. They can swing free up to 90* where they stop and let a high-lift jack catch in. You can barely see on the left, while I was at it I pulled the rear springs apart and added a second main leaf for a tiny bit more lift. They curve around the bottom of the originals to make a semi-"military wrap" to reduce the likelihood of breakage there. Leaf springs do break and when they do you're screwed.
We've had an OK combination of traction and streetability with a Ford Racing posi unit in the rear 8.8, but the front Dana 44 has been open and helped get us stuck a couple of times when one front wheel lost it and wound up just spinning in the air. I had originally wanted what they call a "lunchbox locker" in there, not wishing for the expense and hassle of a selectable, and finally pulled the trigger. I had a bad time trying to research these units, even the supposed off-road experts in their remarks about how these things work only tell you what they do...not how they work. Yeah we know what they do, that's why we'd get one, but understanding operation would help somebody to choose among the three-or-so most common brands. Anyhow, they are comparable to a clutch-type posi if you could imagine you were using the posi clutches only to drive the vehicle and not spider gears, except: Instead of clutch packs on each side there are positive locking splines which can engage/disengage, and instead of side force for that being applied by outward pushing of side gears by spiders, the notches that the big center pin fit through to transfer torque are angled to create side thrust, i.e. input torque causes outward movement of the center "drivers" and engagement into the driven sides which connect to the axles. For one side to disengage around a corner; when pushed along by the outside wheel rather than being driven, half of the driver set can rotate forward a few degrees relative to the other on it's angled pin ramp and release the force on that side, letting things back out enough for free spinning. Small pins with springs under them that come out of a hole on one side and slide around against a flat spot on the other provide pre-load, similar to the spring on a clutch posi. Better pics of all this would help, I know, but I didn't think of grabbing the camera until this point.
What are the big flat spots on the center drivers for? That's just so they can fit into the case...otherwise, they wouldn't go through the hole.
I wound up choosing a locker branded "Spartan". Fits in the stock case like they all are supposed to, looked about like the others, got decent reviews, and I was happy to see when opening the box that everything looked very well made. Seems a little water has been getting in the old diff oil, you can see the cloudy color....since no oil has been leaking out I imagine the seals are still good. The hose on the top case vent had broken away at some point and could have been letting water in there so I guess that's what that was about.
--------------------
On a hillside overlooking a few thousand fellow campers, out for the annual "Tierra Del Sol" off-road meet last weekend. Normally that kind of stuff is too crowded and dusty for me but once a year is OK. We are camped well on the outskirts in the foothills to the right of photo.
We cruised around a bit to check out all the goings-on then...OK let's try that front locker now. This is some pretty soft dirt with a few rocks in it to climb up:
Gets pretty tight in there. A wider vehicle wouldn't have fit, there are a few such places in the Anza-Borrego desert Badlands which is why I've chosen to keep the Cherokee narrow instead of using wider axles/wheel offsets etc. which might be appropriate for other-type offroad areas.
Soft uneven terrain? No problem now, every time a front wheel started to slip the other one took over and pulled us right through. Now we're having fun!
And up over the top. Wonder what that flag on the back of the car is for? That's so somebody coming the other way can see you before flying over the top of the hill and having a head-on collision which is not a totally unusual event. Required safety stuff, much of the time.
What about that locker in normal operation? Is it clunky, does it jerk around a bit/not disengage when it's supposed to, and cause a little steering weirdness? Yes, to all that, to a degree. I don't think I'd use one in the rear of a street vehicle. Up front, when you're not in four-wheel mode the downsides are never noticed.
The Chero on the right is what I originally envisioned building but we've gone different in a few ways. Start with front overhang...believe-it-or-not, that front license plate on our car on the left would only have a few more hours to be straight and undented before I'd be smacking it into a hillside while going up something. (edit: attempting to go up something.) As far back as it is with the bumper style and the front wheelbase pushed out a couple inches, we still catch on things sometimes, with any more crap hanging off the front we'd never have a chance at some of the terrain in our part of the land. You can't see steering shaft/panhard rod angles on ours but with the box lowered and the tie rod points raised we're much closer to level for better road manners, the guy on the right has the more-common but freaky handling offset. Sticking with "small" 32" tires means the spare can go inside and not be on the roof helping to tip the car over, or be out back blocking the view.
Hey look, a carpeted car with a dog on it. The little Isuzu or whatever it is didn't go far without having a tow strap and helper attached to the front.
It's hard to see in this pic but there's a big rock and a puddle of oil under this guy's front diff. He would come out on a tow strap too.
A fun couple of days then off to home. Cheap old truck, cheap old camper, low-budget Jeep that just has some time and effort into it.
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