ZJ axle swap options need input
#1
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Year: 96
Model: Grand Cherokee(ZJ)
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ZJ axle swap options need input
Hey guys, need a ittle input, advise, opinions.. guesses. I have a 96 zj with tired stock axles. I have a brand new set of 37s and I have my finger on the "buy it now" button for the long arm kit but id like to get some axles started first. With my grandma style of wheeling I thought about an 8.8 and beefing up a hp30 just to keep it simple and cost down but having second thoughts. I've looked in to trushing a set of 60s but would push build back and may be a bit overkill even thought I always want a solid foundation. Foolish man builds his house on sand. So with that said are there any other strong but not too expensive options?
#2
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It depends on what you want to do. If your not into rock crawling then a Ford 8.8/ Dana 30 with upgraded shafts may be fine. However I think upgrading to a Dana 44 front may be a good idea. Once you upgrade the shafts in a Dana 30 the ring an pinion becomes the weak link, and with 37s you will want a 4.88 or 5.13 gear ratio and that makes the pinion gear very small on a Dana 30. After seeing how small a 4.88 pinion gear is on a Dana 30 I don't think I would wan't to run any lower than 4.56 gears in a Dana 30, although there is some people who do and don't have any problems. The Dana 44 has a larger gear set and does better with 4.88 or lower gears.
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It depends on what you want to do. If your not into rock crawling then a Ford 8.8/ Dana 30 with upgraded shafts may be fine. However I think upgrading to a Dana 44 front may be a good idea. Once you upgrade the shafts in a Dana 30 the ring an pinion becomes the weak link, and with 37s you will want a 4.88 or 5.13 gear ratio and that makes the pinion gear very small on a Dana 30. After seeing how small a 4.88 pinion gear is on a Dana 30 I don't think I would wan't to run any lower than 4.56 gears in a Dana 30, although there is some people who do and don't have any problems. The Dana 44 has a larger gear set and does better with 4.88 or lower gears.
thanks for the great reply, I forgot to mention that I was looking in to gears. 4.88s just as u said but I was unaware that it the ring in a 30 would be scary thin. As far as brakes it all depended on which axle I picked, deffenitly didn't want to stand on the pedal. For steering I was figuring a hydo assist. Can pick up a lot pretty cheap. Around $300. The dana 44 is a great idea but what came with 1 thats around the same width? 44s from jks are biblically expensive. Even empty housing salvage yards want $1000+
#5
Old fart with a wrench
It's the pinion he was talking about. Engineering standard is 8 teeth minimum for any longevity in a gear train. That makes the ring gear large enough to fill the case to the point where the tooth size must be reduced. Not a good idea.
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gotcha. Sorry I type before my brain can catch up haha. Thats the last thing I want is no longevity.
#7
Old fart with a wrench
From what I can tell, 4.88s are made for the high pinion reverse rotation D30s. You have to change the carrier assembly unless your original ratio was 3.73 or lower in the high pinion axle. I can't find anything lower than 4.56s for the low pinion axle.
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#8
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rough country makes 4.88s for a LP but that's something I wouldn't want to chance. Seems too much mechanical advantage for gear deflection. I have 373 now but if rather start with a HP. I wish there was a front 8.8 that was solid.
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If you want 37s you need 1 ton axles a dana 60 ford front and a rear axle like a gm 14 bolt full float or ford sterling 10.25.For a dana 30 and ford 8.8 35s are the limit on a dana 30 unless you love changing out broken parts a lot.
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#12
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Front and rear D44s will do it also. the XJ unit bearings in the front are not really up to tires that large. Also you will need steering box braces and tie rod upgrades for those 37s
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only problem with 44s is when u can kind them their crazy expensive, at least in NJ. I was looking today and found a set of 1 tons for 650 from a mid 2000s super duty. Probly cheaper then trying to make a d30 last
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A king pin ford dana 60 from the 70s can go for a grand used.I like the super duty axles you get bigger brakes and unit bearings.Only bad thing i can say is they made a dana 50 which looks just like a dana 60 and was used in the super dutys but its stronger then any 44 even beefed up.And keep in mind a super duty has a metric bolt pattern so the old 8 lug rims won't fit it.But oem and aftermarket stuff is out there.