I have been following a couple threads here and on the montero sport online boards,,,, I can see that any sas conversion will take alot of work. I have a 98 montero sport, automatic, running 31 inch tires with no lift currently.

Here's my question to begin with.... is there any difference in the ease of build whether I use chevy, ford, or dodge 1 ton axles? I am planning on running 35 to 37 inch tires. I know I have to regear the axles, and do alot of work. I have a 4x4 shop here in town that does sas conversions on suzukis, so I plan to talk with them as well.

Right now I have a 74 2wd chevy 3/4 ton camper special in the back yard. The Corp 14 rear axle is a 4.10 ratio, and I know I can get brackets to convert to rear disk and use the rest of the hardware off the front brakes. That would give me one axle and I would have to search for a Dana60 front.

Another option is a friend who is selling a late 80's Ford one ton,,, bad clutch and motor, but axles are good. Don't know how much he wants yet.

Options and opinions would be greatly appreciated....

Unless its a superduty ford its twin I beam, fords cool/weird IFS/SFA hybrid. But if it is a superduty that probly means its a d60 driverside drop. If thats the case I'd probly be all over it.

Plans for t case? Are you gonna keep stock motor and what not?

I was under the impression that the 1 ton fords in the mid 80's were not TTB, just the 3/4 ton and below,,, but I could be mistaken....
I am keeping the stock motor, thinking on a jeep np231 case as another build said it will bolt right up and provide me better options...

grap the ford front IMO, 5.38 gears and run 40s with cut fenders, 4-link, coilovers, the works

First, keep in mind you don't need Dana 60+ axles to run 35"-37"s unless you're going to beat the holy crap out of it. I run Dana 44s on my '97 (see www.4x4extremesports.com 'SUV Mods->IFS to Live (Solid) Axle Conversion (SAS)') with a total gear reduction of 230:1 (dual t-cases) and even with the abuse mine gets in 10 years I've NEVER had a problem with the axles not being strong enough. The 3.0L 6G72 only puts out something like 186 ft-lbs of torque. So, unless you plan in the near future to exceed 38"s and/or install a blown V8 those are probably overkill.

You didn't mention if you plan to drive this on the street much but I'll assume so. As I pointed out the 6G72 doesn't put out much power. Dana 60s, 70s, etc. weigh considerably more than a Mitsu axle, Dana 44 or a Ford 9. With 37-38" tires you're adding a LOT of weight. I run 5.38s and those work perfectly for my application only becuase with the 35" tires I run it puts me at the exact same gearing the vehicle came with from the factory. 5.38s are not going to be deep enough on the street for 37-38s and the additional weight. Start looking at gearing in the 5.6-5.8 range. Taller gearing will put a lot of strain on the engine and transmission and your gas millage will totaly suck (no pun intended). :)

That said, if you plan on any serious 'wheeling at the bare minimum change the transfer case gears. I can't remember if Mark sells the 2.85 or the 3:1 for the t-case in the auto Sport. Either will be a HUGE improvement over 1.92:1; if you go high on axle gears you'll need it. Personally, I'd seriously consider swaping to the NP231 with the Tera Low231 4:1 kit or dual t-cases. Either dual NP231s or NP231/Dana. It'll cut the stress on the entire vehicle if you're not having to bonzi every obstacle 'cause your geared too high.

Reason #2 to consider dual t-cases. If you DO decide to go with the Giant Axles from Hell, you're going to have the world shortest front drive shaft (and cruddiest geometry) unless you either move the axle forward a bunch and/or the t-case back. Especially if you don't run a high pinion front axle. Dual NP231s will move the front output back and give you an extra 18" or so of play room. If I remember correctly the 70 moves the u-joint about 3-5" farther towards the rear - but don't quote me. It's been a while. With my original 17" front drive shaft and a D60 I would have ended up with something like a 12-13" inch front drive shaft. :( Running the dual t-case setup also eliminates the need to modify the rear cross member for drive shaft clearance. Nice perk.

One more thing. I'm not sure but I THINK the Mitsu brake master cylinder is would be too small for monster brake calipers. I run GM/Ford calipers and the stock master cylinder is just about perfect but you can tell it's right on the edge. Something to think about since that'll up the cost of doing the conversion.

Edward

Alot of good info there,,, I am planning on running on the street 70 percent give or take,,, so you are saying with 35's or 37's that half ton axles are enough?? Any particular donor vehicle come to mind that would work best to keep residual costs down....
Also, I am looking at a np231 swap for a transfer case, as I have seen here that it seems an option worthy of serious consideration....

Basically, I am trying to get it up off the ground to at least fit 35's,,,,I live in wyoming where we can get deep snow,,, not alot of mud,,,,I want it to be a capable vehicle, but not looking for a rock crawler...

Thanks for the advice and keep it coming, am trying to get the planning stages done now so i don't have to keep buying parts over and over....

on the front axle try a 78 f-250 reverse cut drivers drop dana 44 it is full width but can be shortened on the long side. also the spring perches may need to be moved or brackets made off the outside of the frame rails. mine gave me some grief but it's together now.

I say grab the ford and go to town. Half ton axles would survive but a one tontero would be friggin cool. Look at all the toyota guys running tons with 22re's. Just gear it right and you're good to go. Might want to plan on 40's though, just saying...

good advice all,,,, just in debate to reduce the workload a little bit,,,, don't know if 'yota axles would work beings the width is closer,,, if I should say screw the width and get truck axles from the american trucks, etc.

like i said, 35's to 37's is about all i will go tire size wise,,, i still wanna drive it on the street from time to time,,, this would just be my offroad go play vehicle...

Alot of good info there,,, I am planning on running on the street 70 percent give or take,,, so you are saying with 35's or 37's that half ton axles are enough?? Any particular donor vehicle come to mind that would work best to keep residual costs down....
Also, I am looking at a np231 swap for a transfer case, as I have seen here that it seems an option worthy of serious consideration....

Basically, I am trying to get it up off the ground to at least fit 35's,,,,I live in wyoming where we can get deep snow,,, not alot of mud,,,,I want it to be a capable vehicle, but not looking for a rock crawler...

Thanks for the advice and keep it coming, am trying to get the planning stages done now so i don't have to keep buying parts over and over....

For a 70%/30% vehicle D44s/Ford 9s are fine. Parts are cheap and available everywhere.

The typical problem with 37-38"+ tires on a 1/2 axle is leverage and weight on the knuckles (front) and leverage on the axle shaft (rear) and applying massive amounts of torque and HP and overall vehicle weight and to some extent the type of tire used.

I don't think weight is really anything to consider. Mine typically runs around 6500-6600 lbs GVW wheeling in Moab with lockers front and rear, really sticky tires and 2.72-10.88:1 t-case reduction. I've busted three sets of leaf springs but have yet to have an axle or u-joint problem. I would NOT run 1/2 ton axles in an 8-9000 lb crawler similarly configured. Keep in perspective what you drive - always a good idea. :)

You don't have massive amounts of HP in a 3.0L 6G72 so there's no problem there. And, unless you're planning on running a dual t-case setup with an 11:1 ratio there really isn't that much torque feeding into the axles. An auto is more forgiving, too. You don't have to worry about accidentally dropping the clutch at 5K RPMs.:)

The only real issue is that big tires and rims are HEAVY and the larger the diameter the more leverage there is on the axle shafts, ball joints, bearings, etc. This is totally negligible on the street unless you like smacking curbs at 60 MPH but could be an issue on the trail. If you routinely jam your wheels into crevasses, crank the steering and stomp the gas you'll eventually have problems. But, then again you're not supposed to do that with any axle, so....:)

You can minimize some potential problems by building a 'fuse' into your drive train. Make the weakest link the u-joints in the drive shafts. Ideally the easiest to replace ones. The idea is before getting to the point of twisting off a shaft or busting something in your t-case you'll pop a u-joint in a drive shaft. Replacing a u-joint takes 30 minutes in the field and they're cheap.

OH, almost forgot. Again. Don't forget to reinforce the frame rails before putting the front axle in. Which is something else to consider. The more weight you hang off the front the more stress you'll put on the frame rails. Also a good reason to NOT put more than you really need up there.

No ideas really on the axles. Ford F250 D44 HP would be where I'd start. I have a shop here that will re-tube, align the knuckles and re-weld everything for $150 and cut and re-spline a pair of shafts for $75 so there's not much point for me in trying to find an axle that 'fits'.

Edward

I have been following a couple threads here and on the montero sport online boards,,,, I can see that any sas conversion will take alot of work. I have a 98 montero sport, automatic, running 31 inch tires with no lift currently.

Here's my question to begin with.... is there any difference in the ease of build whether I use chevy, ford, or dodge 1 ton axles? I am planning on running 35 to 37 inch tires. I know I have to regear the axles, and do alot of work. I have a 4x4 shop here in town that does sas conversions on suzukis, so I plan to talk with them as well.

Right now I have a 74 2wd chevy 3/4 ton camper special in the back yard. The Corp 14 rear axle is a 4.10 ratio, and I know I can get brackets to convert to rear disk and use the rest of the hardware off the front brakes. That would give me one axle and I would have to search for a Dana60 front.

Another option is a friend who is selling a late 80's Ford one ton,,, bad clutch and motor, but axles are good. Don't know how much he wants yet.

Options and opinions would be greatly appreciated....

im pretty sure that this is a drivers side drop front pumpkin in stock configuration, if your thinkin bout trying to stay "streetable" look into the jeep waggoneers they have d44 fronts and amc 20 rears hub to hub measurements are bout 3" wider than the mitsubishi. they even retain the same 6 lug pattern so no need to replace your rims, however if your worried bout the 3" you can make it up in the backspacing of your rims, their the same as the half ton chevys and the yotas so aftermarket rims are plentiful on a budget. the 6 cyl 4 speed jeeps had lock in hubs too freebie! just a thought

+1 on the wagoneer axles. front and rear with offset wheels. will hold up to 35's