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Roundeye

Rear diff swap?

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Has anyone here looked at putting an IFS diff (like from a Chevy truck) in the rear of a Subie? Mounting the diff and building converted axles and drive shaft would not be that hard. I have found 3.90:1 ring and pinion sets. But best of all...LOCKERS. Anyone done or tried this? Only problem I could see would be direction of rotation. (or oiling problems if it was inverted)

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if you are going to all of that trouble why not just do something like a toyota 8" or ford 8.8" solid axle? cheaper, way easier, lighter, a lot stronger, better flex probably, plenty of gears, diffs, etc.

if you were doing a prerunner sort of deal, IFS would be pretty cool. you may run into issues with teh diff having an offset to it, one side will have a long extension coming out of the diff to cross over the center line of the truck, transfer cases are usually offset.

with the IFS, you could get HUGE brakes too.

there is also the Jaguar IRS which is very easy crossmember setup and common to put in stuff like hotrods.

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one of the main selling pionts of my sube was the suspension set up all around.I wouldnt put in a live axle ever,becuase I believe with the right work an iFS suspension should out perform a solid axle anyday.ifs is new,solid axles have been around sence horse and buggy days.only so much you can do to something that has existed for 200 years.

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the wheel has been around since the stone age, we still use those. maybe the fact that old technology like the solid axle is still being used is more a testament to its usefulness and effectiveness rather than it being outdated? look at some of the solid axle road cars that can HANDLE. AE86, most rwd volvos, RX-7's, etc. solid axles just plain work for offroading too. leaf springs are not only cheap and rugged but set up right can perfrom very well. links and coils, even better.

maybe in principle independent is better, but in practicality solid axles have some definite advantages especially in slow speed situations where each wheel does not have to react fast individually to uneven bumps. it is possible to have a independent suspension that flexes well, but pretty costly to do so. just depends on what you want it to do. from what I can tell, for slow speed stuff the ruggedness, aftermarket, and articulation of solid axles is a better option than subaru IFS, especially given the low budgets most of us have. just my 2c. I dont have a subaru wheeler but if I build one it will have a transfer case and toyota axles. (flame suit on) everybody do what they want, okay?

but, I'm sure that this debate is :horse:

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So you would say that a Hummer H1 isn't very capable then I take it? Have you driven one? Have you broken one off-road? I have. I would say that IRS and IFS are just really starting to come into their own. Solid axles are going away - even some in the rock crawling community are looking to switch over. Portal systems, and the ability to not have low hanging diffs and no high angle drivelines are just a few of the reasons these systems are taking over nearly every type of automotive application. Articulation is not an issue - the VW Baja community has been running 28 - 30" of travel in the rear of bugs for years. And that's with stock components.

 

GD

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Hummer sucks, I've seen 'em in action. Subaru is way superior.

 

naaah they dont suck they just too damn big... anyways stop highjacking this thread.

 

question was about what diff could be used in the rear, NOT about solid axle vs independant

 

probably heard this before, nissan differantials(like the r200 I think) have some after market and you can get lockers for them.

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Hummer sucks, I've seen 'em in action. Subaru is way superior.

 

based on what?!? so you've seen them in action, but ever followed one down a trail?

 

neither solid, nor independant is superior in everything. they both have their advantages, and disadvantages.

 

 

but back on topic. yes, roundeye, it's been discussed. but usually with toyota IFS stuff, not chevy. AdamNDJ was in the process of making an adapter to mate the toyota front knuckles to the trailing arm in the rear of the subaru, so the diff, and axles could be used. until he got called to duty....search for it.

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rwd volvo's handle well?!? compared to what? a fullsize chevy with 17" of lift and 49" tires?
never driven a 142 with a decent suspension setup and tires have you?:rolleyes:

stick to what you *think* you know about.

 

neither solid, nor independent is superior in everything. they both have their advantages and disadvantages.

totally agree. but it seems like many around here have some vendetta against anything with a solid axle and live in a dream world where lifted/way stiff subaru independent suspension/maxed out CV angles is somehow better than everything else.

 

the VW Baja community has been running 28 - 30" of travel in the rear of bugs for years. And that's with stock components.
sure buddy, whatever you say. in no way are you going to get decent travel out of a bug without stuff like extended trailing arms, 930 CV's, etc. 30" of travel is trophy truck territory. and solid axles going away? funny. independent suspension for a rock crawler is BIG $$$$ simply because capable production parts arent availabe. ever price a custom machined high angle high strength CV joint? there have been what, 2 independent suspension rock buggies, and one has been scrapped and destroyed. its just not cost effective stuff.

for speed over rough terrain, independent suspension is way superior. I'm actually trying to figure out how I can get more wheel travel out of my legacy.

just remember that everything has its place.

 

car IRS like a SVT cobra would be good because there arent any issues with pinion rotation, the diff and axles are damn strong, and its readily available from SVT owners who SWAP IN A SOLID AXLE. hahahah

 

jaguar IRS is heavily used in hot rods, and would be easy to customize to whatever length you need it. anyone who has seen one knows what I mean. oh yeah, it uses a D44 diff. that have enough locker and gear options for yah?

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I only see one hard part to your idea, and you said it would be easy, and that is making the drive shafts that would fit. How would you make them? I would be interested.

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I only see one hard part to your idea, and you said it would be easy, and that is making the drive shafts that would fit. How would you make them? I would be interested.

 

For the axle shafts:

 

1.Cut the Subaru rear axles in half.

 

2. Cut the Chevy/Toyota/whatever axles in half that fit the front/rearend you are using.

 

3. Turn down (on a lathe) the larger diameter of the 2 halfs you have. (OR build up a sleeve for the smaller one)

 

4. fit (sleeve) them into a piece of 4130 chromoly DOM tubing and weld together.

 

5. PRESTO! : You have an axle that has a Subaru outer CV/fitting with a (insert your favorite chunk name here) inner CV/fitting.

 

For the drive shaft: (input)

 

1. Cut off Subaru end of rear Subaru shaft.

 

2. Cut off rear of (whatever) shaft.

 

3. Weld on (whatever) end on Subaru shaft at correct length. This one is critical if you don't want your teeth rattled out whilst driving. And good machine shop can do this and get it true. Balancing would be in order too.

 

Could knock it out in an afternoon.

 

 

TO ALL: To clarify, I am talking about using just a diff out of an IFS or IRS setup that has locker avail. for it. Not a solid axle or any other complete rear end setup. Why? What I am looking at doing can be done without too much work and for not much $$$ with little downtime. Plus I just like 4-wheel independent suspension.

 

And yes, solid axles are on the way out as technology improves on independent systems. Why? One definition of the word independent is: "without influence from another". Just because one tire is on an obstacle, why should the opposite one be tweaked as well? Each of the 4 tires should have it's own suspension to deal with obstacles independently.

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the big reason independant suspension has gotten such a bad name in the offroad community is because typically IFS/IRS is introduced for handling in consumer vehicles, not for off-road performance. As a result, the systems are typically underbuilt for serious thrashing. This is mistaken as being an inherent weakness in the design. However, there is a reason that militaries all over the world are building off-road transports with IFS/IRS. It does perform better in most conditions. The hummer is a bad example because its so damn big and heavy, but hummer suspension on a lighter chassis would rock hard.

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the big reason independant suspension has gotten such a bad name in the offroad community is because typically IFS/IRS is introduced for handling in consumer vehicles, not for off-road performance. As a result, the systems are typically underbuilt for serious thrashing. This is mistaken as being an inherent weakness in the design. However, there is a reason that militaries all over the world are building off-road transports with IFS/IRS. It does perform better in most conditions. The hummer is a bad example because its so damn big and heavy, but hummer suspension on a lighter chassis would rock hard.

 

True that. One undisputeable thing remains: A Hummer would be less capable with solid axles. Two words: Ground Clearance. Have you ever looked under one? Damn.

 

Another example: My Subie has a couple inches more ground clearance than my Jeep Wrangler and my Jeep Cherokee had. They both had lift (which gets you no more ground clearance) and 31x10.50 tires.

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