grant Posted September 25, 2004 Share Posted September 25, 2004 I've been reading about the subaru at http://www.subarubrat.com/ and as much info as I can about the 4wd subaru here. Mostly what I'm looking for is information on the strength of the rear output from the transmission. It sounds like it wasn't designed for primary usage. Has anyone ever had problems with the transfer case mod? I guess if anyone were to have a problem it would be the fellow with the 6 cyl motor. i'm no stranger to custom suspensions and vehicle mods, I've built a F150 into a mud buggy. 2.5 ton rockwell axles and 52" tractor tires. Two NP205 transfer cases, C6 auto, and a 400cuin motor. But I have interest in building something at the opposite end of the weight spectrum. Does anyone know of any solid axle / IFS transfer case photos other than what I listed above? If I were to do this I would have to keep the lowest part of the vehicle halfway between the front and rear tires 23" or lower to the ground. (Alaska highway laws...) Thanks, Grant Quote Link to comment Share on other sites More sharing options...
subarubrat Posted September 25, 2004 Share Posted September 25, 2004 I nuked reverse in one tranny, the second one has been fine. The major problem is stub axles and axle cups. When you run over 3 times the stock HP and tires that big you are pushing what the components can handle. The trannys are pretty stout at stock HP and 30s or under. Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 25, 2004 Share Posted September 25, 2004 It seems to me that the shaft exiting the rear is just as beefy as the one going to the front differential, so the rear output is likely strong enough. You'd be breaking rear independant suspension parts or shattering tranny gears before that shaft breaks. Quote Link to comment Share on other sites More sharing options...
grant Posted September 25, 2004 Author Share Posted September 25, 2004 Thanks. Thats good news about the rear output. However, I won't be using the stock IFS parts. I will most likely get some late model Dana 30-35 jeep front axles and do a SAS (solid axle swap) with front and rear steer (circle and crab steering). My tire chice will probably be 31x10s for street driving and some custom (redneck style) tractor tires for offroad. Still in the concept stages. I hate the newer body styles, so it would have to be ~88 or under. Looking for a non AWD donor vehicle. Hopefully I can find one with a dead diff or something that I wouldn't need. Is there a way to weld the diff (?) in the AWD version to make it equivalent to part time? Quote Link to comment Share on other sites More sharing options...
grant Posted September 25, 2004 Author Share Posted September 25, 2004 subarubrat - Your rear diff in the front was mounted upside down for correct rotation? Quote Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted September 25, 2004 Share Posted September 25, 2004 ive driven plenty of Subarus in RWD with no front CV's, putting all the load on the rear output shaft/driveline/rear Diff/rear CV's and have had no failure at all. I would think the rear output shaft will handle just fine, expecially if you have a Divorced T-Case there to help take the load. With any 1980-1984 4WD Subaru, activating the 4WD (either HI or LO) will lock the rear output shaft to make it a full part-time 4WD vehicle. There is no center diff, so if you kept the Subaru tranny in 4WD, it will always send 50/50 front to rear. -Brian Quote Link to comment Share on other sites More sharing options...
subarubrat Posted September 26, 2004 Share Posted September 26, 2004 The diff is right side up. Here is a pic. Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 26, 2004 Share Posted September 26, 2004 any standard 85-88 dl/gl 4wd manual transmission wagon/sedan should have a 5spd dual range transmission that is locked center 4wd as well. The 5spd DR has a lower low range ratio than the 4spd from 80-84 cars, plus that extra gear of course. Quote Link to comment Share on other sites More sharing options...
grant Posted September 26, 2004 Author Share Posted September 26, 2004 What I tried to say is if I found an AWD subaru manual, how hard is it to weld the center diff into part time? I'll never need to run it THAT often on road. subarubrat - have you hooked a driveshaft up to your front diff yet? I just don't see how it would work unless the nissan transfer case has a reversed rotation output for the front axle. I think you'll need to flip it upside down to the the shafts rotating the right direction? I love what you've done by replacing the front transaxle with a rear diff. I have a buddy up here in Alaska who also thought of that, but never got far enough to figure out if it would work. Take a look at this link: http://www.myhumvee.com/shopdisplayproducts.asp?id=5&cat=Used+Military+Parts I don't know what exactly they are selling (how much of the "hub") but it is interesting. If they're selling pretty much the entire outer knuckle it shouldn't be "too hard" to put those portals onto the subaru. The hubs have a 1.92:1 gear ratio. So it would take about 90MPH at the odometer to get 45mph on the highway. But it would also be possible to mount a transfer case backwards to go on the highway... Probably a little too much for this audience... Quote Link to comment Share on other sites More sharing options...
Rooinater Posted September 26, 2004 Share Posted September 26, 2004 it works just fine. there's no reverse rotation. i have the same tcase setup at the moment. but a new project is coming along when i get out of iraq... Qman if you look in the gallery has a solid rear axle. and mtsfabman (or something like that) has an xt with yota axles front and rear. have fun with it! my next one will get me banned from the board... hahaha... doubt it, but probably will push it... also can check my website below if you wish. it has some pictures there too. not much since the tcase mod... but when i get back i'll get a ton more. i just bought a 1000 dollar digi camera... pic happy!! Semper Fidelis, Jared Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 26, 2004 Share Posted September 26, 2004 Well, there's only 1 person I know of who locked up an awd transmission and it was an automatic tranny, which I think means that the rear output is activated by a computer controlled clutch. However a manual tranny has a viscous coupling, so locking it up would be a whole different deal. Anyways, I'm pretty sure the viscous coupling can be pulled out the back of the tranny. I think that's something you'll have to dive into yourself. You were saying that you want to run an early 80's body style right? Just letting you know that you won't find an awd box stock in one of these cars. If you find an awd box it will be in a 90's model subaru and it will only bolt up to the "ej" series engines from 90's model subarus. 80's soobs have the ea81 ohv motor or the ea82 ohc motor (found in mid-late 80s cars). Only the 80's models come with dual range transmissions. So it's up to you whether you want to run a lower power but simpler ea series engine with the extra gear reduction from the dual range tranny, or if you want the more powerful (but more wiring) ej motor, without the reduction, and figure out how to lock up the awd tranny. If you grab a subaru diff and play around with it you'll figure out the rotation stuff. It's hard to visualize but it works. Quote Link to comment Share on other sites More sharing options...
grant Posted September 26, 2004 Author Share Posted September 26, 2004 Sorry guys, don't know what I was thinking. I have a D44 IFS diff in the garage and I guess somehow I played with it wrong. Anyway, glad I was worng! I was spinning it the same direction in both orientations, when in reality it would be swapped... It seems like I've got some of the best axle mod guys already reading this thread, so I won't start a new one. Has anyone ever thought of building an assembly to bolt the rear IRS parts to that would articulate itself? so you would have the best of both worlds? Handling and articulation? Its a very interesting thought at the least... Quote Link to comment Share on other sites More sharing options...
subarubrat Posted September 26, 2004 Share Posted September 26, 2004 subarubrat - have you hooked a driveshaft up to your front diff yet? I just don't see how it would work unless the nissan transfer case has a reversed rotation output for the front axle. I think you'll need to flip it upside down to the the shafts rotating the right direction? Dude, I have been running it that way for a year, I assure you it works. The truck is finished and the shaft is in place. That pic was during construction. Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 26, 2004 Share Posted September 26, 2004 It seems like I've got some of the best axle mod guys already reading this thread, so I won't start a new one. Has anyone ever thought of building an assembly to bolt the rear IRS parts to that would articulate itself? so you would have the best of both worlds? Handling and articulation? Its a very interesting thought at the least... Some people have done this with hummer stuff right? It would be cool, except for the fact that the rear end is a huge weak link in these cars. The r160 rear diff has a 6.3" ring gear and 23 spline hollow stub shafts, and the cv axles like to blow up as well. It's probably weaker than a samurai rear axle. That's the main reason people are sticking solid axles in the back. Id rather have independant suspension if I could keep it strong enough, I like the way it handles when I'm burning around on trails, or how I get 15" of clearance under the diff with only 31" tires. Quote Link to comment Share on other sites More sharing options...
Adam N.D.J. Posted September 27, 2004 Share Posted September 27, 2004 The rear output shaft on the Soob tranny is pretty strong, but the problem is that the rear is actuated by a clutch just like a regular gear, the 4spd tends to be pretty weak, I shredded a rear output syncro with stock 4wd components, 29" tires, and a warmed over 1.8L Then with the 6cylinder I shredded a high range syncro pulling out of my carport for the first test run with the new motor. I switch over to a dual range 5spd and haven't had one problem yet. The tranny is always in 4wd, feeding into the Nissan T-case. I have been into some really nasty situation where's I have completely blown up rear axles and the trans didn't even notice, I've done a 5K clutch drop, pulling the front tires off the ground, and the tranny was happy as a clam. If you want some more pictures for research here are all mine on my rig, it's basically the same setup as Subaru Brat except I have a smaller lift and went a little different direction on some things. http://usmb.net/gallery/albun96 Quote Link to comment Share on other sites More sharing options...
Rooinater Posted September 27, 2004 Share Posted September 27, 2004 GD was talking about hummer stuff awhile ago. but i haven't seen anyone do it yet. it's only a matter of time. as for the use of another irs in the back. i'm just trying to get rid of it. clearance is nice... but riding like a tank in the arizona rocks... isn't very nice. so i'm just waiting to get back on us soil. my lil' roo is getting a yota rear axle. then another project coming to. Quote Link to comment Share on other sites More sharing options...
grant Posted September 27, 2004 Author Share Posted September 27, 2004 I think I have my plan straight. I'm going to obtain some Jeep Dana 35 reject axles and do front and rear steer. I've got a zuk transfer case lined up for the project. I'll probably start the project if everything goes well sometime around the beginning of November. For tires I will be making cheveron tractor tires out of bald 265/75R16s and angle iron. Might run duallys all the way around... Alaska liftlaws limit me to 23" on the unibody, so I might have to weld in some factory "option" unibody stiffeners. Thanks for the advice. The one I've found so far is a 5 speed. Maybe the 5 speed has more beef due to the lower 1st and the dual range? Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 27, 2004 Share Posted September 27, 2004 Could you run the tractor tire idea by me again? I don't understand where the angle iron comes into play for some reason it sounds like alaska lift limits will be the least of your worries if caught on the road. Quote Link to comment Share on other sites More sharing options...
grant Posted September 27, 2004 Author Share Posted September 27, 2004 The good pictures are back up, so if you haven't seen the thread already...check it out. http://www.ultimatesubaru.org/forum/showthread.php?t=22307 I don't know exactly how I plan to make my tires yet. I will know after it snows a few times. First off I need to experiment to see if angle iron BOLTED to a tire will wear too quickly. I am going build 4 different ideas and test them on each wheel of the plow truck: -1. Tire chains fixed to the rim (using bolts as shackles to eyelets welded to the rim?) -2. Angle iron used over the tread surface instead of chain. (like steel paddles) Chain will be used to attach them to the tire. -3. Angle iron bolted to the tread with a tube to hold air. Use hex cap head bolts with large fender washers on the inside with a nylock nut on the outside. -4. Angle iron in a chevron pattern bolted to the tread... I'm also going to experiment with different air pressures to see which is better for extreme traction in snow and ice. Enough pressure to let the rubber conform around the steel, or the side wall listed pressure. I am not doing this initial test to validate traction performance in offroad situations, this test will be to gauge the dammage caused by drilling holes through and bolting steel to a tire. I figure a plow truck would be the best method to test the ideas, since plow trucks are heavy and transfer a large amount of torque to the ground. I would not try driving it on the road. So either I bring a spare set of tires or trailer the thing. In the case that chaining steel to a tire works, I could chain the inner set of tires and build a custom set of duallys that bolt to the inner rim. So I bring an extra set of tires on top and "bolt" them on later. Of course all that extra usage stuff I mentioned is just logistics at this point. All I want to do for now is drill holes in tires and bolt steel to them. Its like an unscripted version of the Red Green show. Quote Link to comment Share on other sites More sharing options...
grant Posted September 27, 2004 Author Share Posted September 27, 2004 I forgot to mention that I also want to experiment with bridging the gap between the dual tires. I have experience cutting up tires, so I figure that the tread surface from little car tires could be wrapped around the tires and affixed somehow. Haven't quite worked out how that would be done yet. Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 27, 2004 Share Posted September 27, 2004 what about running tubes? then you don't have to worry about your joints or drilled holes holding air, just the forces on the rubber. Of course you have to be careful not to wear holes in the tubes from sharp edges. As for joining the rubber, It's vulcanized, I have no idea how it could be done chemically or if they could be melted together. BTW I want to see some of those CNC plasma goodies on this thing edit #2: More t-case stuff in my album: http://www.ultimatesubaru.org/photos/showgallery.php?cat=500&ppuser=129 Quote Link to comment Share on other sites More sharing options...
grant Posted September 27, 2004 Author Share Posted September 27, 2004 I think I mentioned tubes earlier. That's the reason for the cap head bolts. I was setting up a computer at work when I had another idea. cut most of the side wall out of two tires and then bolt two tires together. Widen a rim, then bolt on angle. These ideas may sound crazy, but I have a way of making them look good and work at the same time. Quote Link to comment Share on other sites More sharing options...
bushbasher Posted September 28, 2004 Share Posted September 28, 2004 So your saying that the bolts woudl be horizontal joining sidewall to sidewall? Wouldnt the tire balloon out in the middle? Quote Link to comment Share on other sites More sharing options...
grant Posted September 28, 2004 Author Share Posted September 28, 2004 Who knows??? I might not want to try it with my small selection of R16 tires, so I'll do it to some 29" R15s. Its worth doing at least once. Thats how the good pictures for the internet are made! So maybe I don't cut the sidewall out. Then the bead should keep things round. Probably need two tubes too... If you could do me a favor...what you've got going with that 4 door wagon is similar to what I want. However, I have no wagon yet. Could you measure: -from the top of your diff to the engine, or whatever it -would- hit first if it could move -from the top of your diff to the ground -from the unibody rail, the main structural part of the unibody, half way between the front and rear tires to the ground? In other words, rail to ground? Also, what size tires do you have? If I can get that info, I should have enough to draft something up to see how it will all fit. Might be able to photochop it together. And if its not too much trouble, a picture looking up from the ground into the engine compartment on the pass and driver side? Want to see how a straight front axle with offset diff would complicate things. The CNC will be used on this project. I'm thinking about doing rear steer with a manual steering box, winch motor, chain and sprocket, and a subaru disc brake. Watch out... Quote Link to comment Share on other sites More sharing options...
Rooinater Posted September 28, 2004 Share Posted September 28, 2004 uhhh... they sell tractor tires for 14 and 15 inch rims... no need to create them... they are a little closer to street legal too.... Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.