37s on a half ton with a 12 bolt with 4.10 gears

Craig 85

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Another question: do you have to have 1 ton suspension to run 1 ton axles. I am wanting to buy the 6 in rc lift for the half ton but I am wondering if I would need to get the one ton kit instead?

No. This truck had a 4" Tuff Country EZ Ride front springs with a 4" rear block and the stock 1/2 ton rear springs. With the ORD sway bar disconnect kit, it was the best riding 4WD Square Body I've had out of the 6 I've owned.

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shiftpro

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No. This truck had a 4" Tuff Country EZ Ride front springs with a 4" rear block and the stock 1/2 ton rear springs. With the ORD sway bar disconnect kit, it was the best riding 4WD Square Body I've had out of the 6 I've owned.

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Still one of my favs on this site.
 

Isaac nickerson

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Glad to help.
You notice how a lift spring has arch to it. Well what happens when it compresses? It gets longer. And without extra shackle length the rear leaf eye will smack the frame. THAT is why old school lift spring have such higher spring rates... to prevent them from compressing enough to bang the frame.
And banging the frame hurts! Plus lowering the rear of the leaf increases the trail... which lends to handling and self centering the front wheels after a corner. All our beloved squares can use a bit more trail... even with the slight extra angle imposed on the front lower U joint.

I never addressed the rear end around lifting. I mean a D60, one ton front end, will lift the truck. But since you brought up the rear axle, you can use blocks but they add to wheel hop and are gay. You can invest on a lift spring or best... shackle reverse kit from ORD or DIY4x4.

Brakes...
the thing about one ton trucks that is always a win are the juice brakes. Hydro pressure comes from the power steering pump rather than the vacuum boost a 1/2 or 3/4 ton has. THESE brakes lock up 40" tires and you wanna see hippies get out of the way?

Rear discs are the way to go imo. You can use 3/4 ton front rotors and an aftermarket mounting plate. You can also run 3/4 front discs on a one ton with the proper bracket. They are just as strong as the bigger one ton rotors, but you get a better modulation and take some 35ish lbs off each front wheel.

Rear discs do not have an emergency brake unless you use Caddy brakes from the mid 70's. Once you figure the trick to bleeding them and setting them up, IF YOU USE THEM OFTEN they will give good service. If you're in to mud you will ansolutely need to keep them clean.

Back to the front end with a 4" lift spring.
Best bang for buck are Tough Country. They have the proper spring rate. If you have the $$ you can do better with a a custom ORD or Deaver Spring multi leaf pack. More leafs, but thinner. Great flex, better ride all around.
With a 4" lift it's still a good idea to use a raised steering arm. Or a lowered pitman but these put more stress on the steering box and frame.
Or the ultimate **** OFF steering is cross over.. using a 2wd steering box. You can search this out and come back for more info after your homework.

We're starting to get gnarly here..
Haha yeah. I will read up on it. I have heard a lot about frame issues where the steering box mounts.
 

Rumbledawg

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lots of good info shiftpro.
having owned approx 7 or 8 lifted squares, for anything bigger than 35's, 1 ton axles are best unless you just road drive 'em.
1 tons also come wit a factory steering box brace that i find is plenty skookum. can get them for practically free at the wrecking yards.
not always necessary to lengthen d-shafts either. my crew has an 8" lift with factory shafts. the rear is 2 piece that i put a 2" spacer on the carrier bearing, the slip pulled out about a 1/2", but unless i get real stupid i still have 4" of slip left. the front is a cv shaft that i ground out the "stops" and added a longer slip yoke. i should mention i did also drop the t-case 1".
wit big tires, hydro is THE WAY to go...or stop. wit hydro you won't really need to disc the rear. i redid my entire braking system from the master cyc back wit "premium" parts, and for a 8000lb truck, it will haul down extremely fast, even with my camper on and quad trailer in tow, and yes, my quad trailer has no brakes...yet...
and over 4" lift and 35's, crossover is the best. forget about steering blocks and them dumb "s" shaped drag links. i used to run a dropped pitman, "s" drag link and a 3" steering block, fine if you want to be a pavement princess, but wait till your all flexed up and you turn the steering wheel and your tires are still pointing forward...can make for a pucker moment. with crossover i run a 2" drop pitman and that's it. you will have to ditch your swaybar though
i run 38" radials or 42" bias swamps with 4:56's and they are fine. it's not a drag truck, far from it, but with 600 lbs of torque, 4:56's, a detroit and almost 3 feet of rubber, it will literally snap off the line. i've managed to holeshot a few five point nuthings, some hopped hondas and the odd camaro off the line...for about 60 feet or so...sure does make for some dumbfounded looks from some guys that expect to spank that 'old 4x4 sitting next to them at the lights
 

Isaac nickerson

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lots of good info shiftpro.
having owned approx 7 or 8 lifted squares, for anything bigger than 35's, 1 ton axles are best unless you just road drive 'em.
1 tons also come wit a factory steering box brace that i find is plenty skookum. can get them for practically free at the wrecking yards.
not always necessary to lengthen d-shafts either. my crew has an 8" lift with factory shafts. the rear is 2 piece that i put a 2" spacer on the carrier bearing, the slip pulled out about a 1/2", but unless i get real stupid i still have 4" of slip left. the front is a cv shaft that i ground out the "stops" and added a longer slip yoke. i should mention i did also drop the t-case 1".
wit big tires, hydro is THE WAY to go...or stop. wit hydro you won't really need to disc the rear. i redid my entire braking system from the master cyc back wit "premium" parts, and for a 8000lb truck, it will haul down extremely fast, even with my camper on and quad trailer in tow, and yes, my quad trailer has no brakes...yet...
and over 4" lift and 35's, crossover is the best. forget about steering blocks and them dumb "s" shaped drag links. i used to run a dropped pitman, "s" drag link and a 3" steering block, fine if you want to be a pavement princess, but wait till your all flexed up and you turn the steering wheel and your tires are still pointing forward...can make for a pucker moment. with crossover i run a 2" drop pitman and that's it. you will have to ditch your swaybar though
i run 38" radials or 42" bias swamps with 4:56's and they are fine. it's not a drag truck, far from it, but with 600 lbs of torque, 4:56's, a detroit and almost 3 feet of rubber, it will literally snap off the line. i've managed to holeshot a few five point nuthings, some hopped hondas and the odd camaro off the line...for about 60 feet or so...sure does make for some dumbfounded looks from some guys that expect to spank that 'old 4x4 sitting next to them at the lights
Thanks for the info. Question. Is there like a crossover steering kit you can buy? or is it something you have to custom make?
 

Hondo78

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Hey all, wondering if doing 37s on a half ton with 12 bolt n

Yes that combination will work; I have driven my K5 for eight years lifted , I did add a modern over drive transmission once they were available used so if you switch to a NV4500 you get a lower first gear and the over dive gear. I ran my K5 with 40's for two years, 'kind of poor mannered at highway speed, but worked great both off and on road. I even pulled my V-Drive to and from the river with that truck, and to Tahoe to ski in winter. (Just watch your wheel bearings and u joints quarterly)
 

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Yes that combination will work; I have driven my K5 for eight years lifted , I did add a modern over drive transmission once they were available used so if you switch to a NV4500 you get a lower first gear and the over dive gear. I ran my K5 with 40's for two years, 'kind of poor mannered at highway speed, but worked great both off and on road. I even pulled my V-Drive to and from the river with that truck, and to Tahoe to ski in winter. (Just watch your wheel bearings and u joints quarterly)

Highly trimmed fenders?
 

Raider L

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@Isaac nickerson,

I think you need to stop for a second, take a breath and then really think about, " What are you going to use your truck for and for how much?" Before you dive off into all kinds of mods that bring all kinds of associated changes and costs as well, it may be more trouble than it's worth if you're not going to really use all these mods. Some of those may be something you could start with like the rear brakes, but you may not need to change leaf springs and all of that if you really aren't going to need all of that.

There is the cost as well. You may not be able to find people who would sell you a bunch of things like rear ends, leaf spring sets for little to nothing. You may end up having to spend a bunch of money you may not have wanted to spend later on when you look back.
There is a lot you could do with what you have. 12 bolt rear ends can be modded with ring and pinion gear changes and a ton of other heavy duty stuff less expensive, and may work out just fine, "for what you really needed", and a TH350 can take a lot of abuse before you'd need to make a really big change like going to a 14 bolt. Look into modding the TH350, heavy duty clutch disc sets, torque converters, shift kits, etc., and maybe recurving your leaf springs before going off the deep end with big everything just to end up driving down a dirt road and you never see deep sticky mud two feet deep, water up to the fenders, whenches, hooks, chains and all.
You know?? Compare what you've got first, beefing up the 12 bolt, your leaf springs, etc., before you chunk it all for something you may not need or need to do.

Don't forget all the suspension geometry changes you'll have to make when you start making lift changes, and the cost of doing all that when you go with bigger tires, lift kits and all, angle changes to the pinion as you lift your truck up. And what that will do to how it drives after all those changes. Do your homework, I mean really do your homework before you take anything off or make any changes.

But have fun and it will all be much more interesting and you will learn a lot!
 

Isaac nickerson

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Thanks I appreciate the input. Just for the record its a sm465 nit a th350. I will definitely research and as it is i am considering a smaller lift and tires due to probably not needing that much tire because of the level of offroad Ill be doing.
 

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You have received a lot of good comments, so I guess I'll put my 2 cents in. I have run everything from 35" Haugs on 1/2 tons, to 44" Gateway Gumbo's on ton, to 48" Goodyear flotations on Rockwells, and can tell you it really just depends on what you will be doing with the truck. You said you would be wheeling it quite a bit, and that's when 1/2 tons have problems. I have personally watched my right rear 39.5" Super Swamper pass me going down the highway at 60 mph after a day of 4 wheeling. These problems usually come up when going from slick mud to hard packed dirt or rock, something will eventually break, u-joint, axle, wheel lugs. If you're going to be wheeling, I would recommend not going more than 33s with 1/2 tons. With 3/4 ton you should be fairly safe up to 38, but keep a front joint and spare long side front axle shaft with you, they are easy enough to replace in the field. Your SM465 and probably NP205 are a great start and your truck should never feel sluggish, that's what I've been running for years with every tire size, and no issues yet. Also, check your frame at the steering box, if it's cracked you need to fix it and add a reinforcing kit, if not at least add a reinforcing kit. It's not fun having your frame break and loose your steering
 

Isaac nickerson

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You have received a lot of good comments, so I guess I'll put my 2 cents in. I have run everything from 35" Haugs on 1/2 tons, to 44" Gateway Gumbo's on ton, to 48" Goodyear flotations on Rockwells, and can tell you it really just depends on what you will be doing with the truck. You said you would be wheeling it quite a bit, and that's when 1/2 tons have problems. I have personally watched my right rear 39.5" Super Swamper pass me going down the highway at 60 mph after a day of 4 wheeling. These problems usually come up when going from slick mud to hard packed dirt or rock, something will eventually break, u-joint, axle, wheel lugs. If you're going to be wheeling, I would recommend not going more than 33s with 1/2 tons. With 3/4 ton you should be fairly safe up to 38, but keep a front joint and spare long side front axle shaft with you, they are easy enough to replace in the field. Your SM465 and probably NP205 are a great start and your truck should never feel sluggish, that's what I've been running for years with every tire size, and no issues yet. Also, check your frame at the steering box, if it's cracked you need to fix it and add a reinforcing kit, if not at least add a reinforcing kit. It's not fun having your frame break and loose your steering
Thanks for the tips. I will definitely add that reinforcement kit. After all my research and from what I have heard on here and looking at prices My thought is to keep the half tons, wait on 37s and do 35s with a 4 to 6 inch lift. Once something serious breaks on the half tons I think i will do an axle swap to a 14 bolt and dana 60. I would like to do it all at once but Im 17 and just don't have the funds between my truck and my Ktm :) Anyone have thoughts about that plan?
 

Juggernaut

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Thanks for the tips. I will definitely add that reinforcement kit. After all my research and from what I have heard on here and looking at prices My thought is to keep the half tons, wait on 37s and do 35s with a 4 to 6 inch lift. Once something serious breaks on the half tons I think i will do an axle swap to a 14 bolt and dana 60. I would like to do it all at once but Im 17 and just don't have the funds between my truck and my Ktm :) Anyone have thoughts about that plan?
I feel you young man, you're exactly where I was at in 1989, trying to pay for my 78 on a Burger King salary! So here are some of the tips I learned the hard way. First, if you have any leaks, fix them. If oil can get out, water and mud can get in. Make sure ALL of your vent hoses are clear, and ran up high to where water can't get in. Use hose clamps at the vent pipes to keep the hoses sealed up and in place. There's vents on both axles, transfer case, and transmission. When I was running 35s with 1/2 tons I broke a LOT of u-joints, usually at the front axle, and front drive shaft, but occasionally at the rear drive shaft at the transfer case. Keep some cheap joints, a hammer, old socket the size of the joint cap, and some hand tools with you when you go wheeling. You will eventually have to change one. As far as lifts go, 6" will put more strain on the front CV joint at the transfer case and you will break it. With 35s you're better off going with a 4" kit and trimming your front fenders. If you know you eventually want 37 or 38s and bigger axles, you can get the 6 or 8" kit, but you should replace the front drive shaft and output yoke on the transfer case with a u-joint only and get rid of the CV. Costs more money but well worth it to avoid CV breakage
 

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