hodges81
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:huh:Has anybody changed the transfer case to selectable 2 wheel / 4 wheel drive? It should help mpg and in power... Due to parasitic loss... Any thoughts or input?
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Changing transfer case to selectable 2 wheel / 4 wheel in H3
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Corey Barnes
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- Mobile, AL
I wish someone would that would be sweet!!
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Corey Barnes
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- Mobile, AL
Burnouts and donuts in the 3 haha
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Highatop
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And fish tails... Thought 4speed was brainstormin that one right now...
Not sure about burnouts, but talk to Kyle about donuts. Sets of side airbags if you have them and eventually totals a 3. Damn concrete poles [emoji33]
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Unless you get hubs that unlock, you'll have the same friction within the system as the CVs, front diff and propshaft will still be turning.
Corey Barnes
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Yeah I seen that def want to stay away from the donuts and concrete poles after his encounter with them...
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ReconH3
Guardian Angel
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It's a very complicated process due to electronics. Some of have researched doing it with an Atlas and have run into a ton of issues. Not saying it can't be done. Just haven't figured it out yet due to all the annoying electronics.
"Ex Umbris Venimus"
"Ex Umbris Venimus"
Mb30sdl
Hamster that pokes Bears
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Atlas is in H2, when it comes back from the shop I'll be dealing with this issue. Having dana60 with danalocks helps.
4speedfunk
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Yeah...obviously, the "2WD MOD" requires both a 2WD t-case AND free-spinning hubs. Most of us that have done some sort of axle swap, already have the hub situation taken care of (lock-outs). But we still need some sort of t-case with a 2WD mode. Finding a t-case with a passenger-side drop is not the issue...finding one that will work with the H3's electronics, is. Given the task at hand...I think it might be easier to mod the stock t-case to yield a 2WD mode, than it would be to adapt some other t-case to work with the electronics and fit the H3.
I have not had the 4494 apart yet...but I have a smoked one sitting here on my work bench, awaiting a tear-down. I cannot say for sure...but I believe the H3's "variable f-to-r torque split" is done via something mechanical and not done with any sort of electronics. I say this because when mine started failing...I never got any sort of dash light indicating something was wrong. It was just harsh mechanical binding and grinding. So, whatever dohinky controls the variable split...I think it is entirely mechanical. Thats good news for doing some sort of mod. Whatever the case (no pun)...I think the "electronics" of the H3 t-case is limited entirely to the selection of the mode. The encoder motor clearly rotates a shaft to switch modes...but I don't see any other sensors or wires that would be used to control or vary the output to the front shaft....and I also don't think the encoder motor is actuating anything by itself (it seems to only work via the buttons on the dash) as you drive down the road. So my theory is that the torque sensing and variable output is done entirely inside the case via some sort of mechanical system. I could be wrong on this but, its a hunch I got.
My plan is to leave the encoder motor alone...leave the shift forks alone...and somehow swap out the variable front/rear drive gear (4HI-Street mode) for a fixed rear-only drive gear. I have no idea how to do this but, it seems this might be the easiest path to a 2WD case. Essentially the 4HI-Street button on the dash would become a 2HI-Locked. You would loose the variable f-to-r mechanism that the H3 normally uses in 4HI-street mode...and you would be left with a traditional 2HI-4HI-4LO case like everything else uses. My main concern after reaching this point would be to make sure the truck can drive down the road without lighting up the dash, and all the traction systems work correctly. Then my secondary concern would be the longevity of the t-case itself. Shutting off the front output shaft means the that the rest of the t-case must be able to freely spin and operate the rear output...but safely let the front output remain motionless, without burning something up. Not sure what kind of lubrication issues I could get into...probably depends on how the variable split dohinky works.
I have not had the 4494 apart yet...but I have a smoked one sitting here on my work bench, awaiting a tear-down. I cannot say for sure...but I believe the H3's "variable f-to-r torque split" is done via something mechanical and not done with any sort of electronics. I say this because when mine started failing...I never got any sort of dash light indicating something was wrong. It was just harsh mechanical binding and grinding. So, whatever dohinky controls the variable split...I think it is entirely mechanical. Thats good news for doing some sort of mod. Whatever the case (no pun)...I think the "electronics" of the H3 t-case is limited entirely to the selection of the mode. The encoder motor clearly rotates a shaft to switch modes...but I don't see any other sensors or wires that would be used to control or vary the output to the front shaft....and I also don't think the encoder motor is actuating anything by itself (it seems to only work via the buttons on the dash) as you drive down the road. So my theory is that the torque sensing and variable output is done entirely inside the case via some sort of mechanical system. I could be wrong on this but, its a hunch I got.
My plan is to leave the encoder motor alone...leave the shift forks alone...and somehow swap out the variable front/rear drive gear (4HI-Street mode) for a fixed rear-only drive gear. I have no idea how to do this but, it seems this might be the easiest path to a 2WD case. Essentially the 4HI-Street button on the dash would become a 2HI-Locked. You would loose the variable f-to-r mechanism that the H3 normally uses in 4HI-street mode...and you would be left with a traditional 2HI-4HI-4LO case like everything else uses. My main concern after reaching this point would be to make sure the truck can drive down the road without lighting up the dash, and all the traction systems work correctly. Then my secondary concern would be the longevity of the t-case itself. Shutting off the front output shaft means the that the rest of the t-case must be able to freely spin and operate the rear output...but safely let the front output remain motionless, without burning something up. Not sure what kind of lubrication issues I could get into...probably depends on how the variable split dohinky works.
Kurt
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Seems like an awfuly complicated and expensive procedure at the cost of reliability for questionable returns on ... fuel ecomony.
4speedfunk
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Won't know until I get the t-case apart...I'm hoping around $200 or so.
Reliablility? hard to say
Fuel econmy? probably 2 mpg
The real reason is to save wear & tear on front axle parts.
Reliablility? hard to say
Fuel econmy? probably 2 mpg
The real reason is to save wear & tear on front axle parts.
RamRod
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Lets get serious, the real reason is to drift around do donuts on the snow covered roads 
(wait! what? not all of you live with roads covered in snow for 8 months of the year??:swear
(wait! what? not all of you live with roads covered in snow for 8 months of the year??:swear
4speedfunk
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Busted!
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06 H3
a.k.a. "The Jackal"
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I'm torn when it comes to the t case with full time 4wd. I see both sides to the story. Personally 2wd is kinda useless to me if the front end is spinning. The lock out hubs don't even come with JKs TJs YJs so you have 2wd but your still spinning everything. Granted it still might be less drag then full time 4 but there's still drag and if parts fail your still munching away at those parts driving home.
That's why the locking hubs are great. Save driveline wear, especially double cardans, save front end parts and best of all blow the front end up unlock the hubs put it in 2wd and you now can drive home without possibly destroying more parts.
I don't like lock out hubs because people can **** with them, bouncing on the trail a hub can come unlocked (not likely but possible) they stick out farther then regular hubs so you can hit them. And if your in a situation where you need to hit the dirt fast you have to stop and lock them.
Now onto the actual t case...I don't live in a snowy area but I have driven in the snow multiple times and I think the 4hi street kicks ass it never skips a beat. Where my brother he's in 2wd then he's spinning then he stops and puts it in 4hi then he hits a dry section of the road and it's binding and seeing he's crazy he thinks the t case will implode due to the binding on the street. So we stop again to put in back in 2wd. All while I'm just driving around, no binding no anything. That's why I love the full time 4 but my personal favorite case of all time is the NP242. Kinda rare but they have 2hi 4hi unlocked (just like our h3s) 4 hi locked 4 lo locked. So when you want 2wd you have it. In bad weather and you want 4wd without binding like if the road is partially plowed you have 4wd if you want 4hi locked for higher speed stuff where traction sucks offroad you have it then you have your traditional 4lo too.
I don't think the computer will trip out if you swap out the t case coupler for 2hi. When I was in 4hi unlocked with no diff I wasn't going anywhere. Just revving up. My traction lights weren't even going off trying to find traction oddly enough but that was also in front of my house without going anywhere.
That's why the locking hubs are great. Save driveline wear, especially double cardans, save front end parts and best of all blow the front end up unlock the hubs put it in 2wd and you now can drive home without possibly destroying more parts.
I don't like lock out hubs because people can **** with them, bouncing on the trail a hub can come unlocked (not likely but possible) they stick out farther then regular hubs so you can hit them. And if your in a situation where you need to hit the dirt fast you have to stop and lock them.
Now onto the actual t case...I don't live in a snowy area but I have driven in the snow multiple times and I think the 4hi street kicks ass it never skips a beat. Where my brother he's in 2wd then he's spinning then he stops and puts it in 4hi then he hits a dry section of the road and it's binding and seeing he's crazy he thinks the t case will implode due to the binding on the street. So we stop again to put in back in 2wd. All while I'm just driving around, no binding no anything. That's why I love the full time 4 but my personal favorite case of all time is the NP242. Kinda rare but they have 2hi 4hi unlocked (just like our h3s) 4 hi locked 4 lo locked. So when you want 2wd you have it. In bad weather and you want 4wd without binding like if the road is partially plowed you have 4wd if you want 4hi locked for higher speed stuff where traction sucks offroad you have it then you have your traditional 4lo too.
I don't think the computer will trip out if you swap out the t case coupler for 2hi. When I was in 4hi unlocked with no diff I wasn't going anywhere. Just revving up. My traction lights weren't even going off trying to find traction oddly enough but that was also in front of my house without going anywhere.
RamRod
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Having 2hi, 4hi unlocked, 4 hi locked & 4 lo locked would be the bee's knee's!!!! hahahha
But seriously if it were possible thats what i would want! in winter when i hope out of my truck then into a RWD truck I am alway surprised at how much more traction I am about to maintain in my T at all times!
But seriously if it were possible thats what i would want! in winter when i hope out of my truck then into a RWD truck I am alway surprised at how much more traction I am about to maintain in my T at all times!
4speedfunk
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I think that's what my 99 Burban K2500 (480LE/IFS) has. Its got four modes...2HI, 4HI, 4LO, and Autotrac. I've never used the Autotrac mode. I assume the Autotrac works in conjunction with the CAD on the front IFS, and cycles itself in and out of 4WD base on some sort of privileged information coming from the puter. Its drivers-side drop of course, so its useless for the H3 anyway (unless you SAS it with a ds drop front axle). Also it has a typical 2.5-ish:1 low range and not the 4:1 that I have come to love about the H3. I'm pretty sure there is an aftermarket crawler kit available for the 242.
I haven't even checked but, the full-size SAS crowd says the Autotrac t-case won't work with the solid axle because it uses a slip yoke on the front output. This would be problematic with a live front axle, and you would need something with a flange on it, so you don't pull the yoke out of the t-case. Pretty much everybody doing anything custom with 4WD's uses a traditional 3-mode case, (NP205) and manual lock-outs on the hubs. Its so simple, logical, and hassle free, that its hard to argue with. It seems every attempt to make a 4WD more user friendly results in an overly complex rube-goldberg type system. I'm back-dating my Burban to lock-outs, solid axle, and sticks thru the floor....the way god meant it to be.
After that....saving for the Cummins 24v and 5-speed manual swap.
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Pretty sure all the electronic stuff is controlled thru the ABS Pump/Modulator/ABS traction control PCM. The transfer case electronics should just consist of a motor to switch between modes.
A 97-06 Jeep Wrangler is a part time system without the use of hubs. The axle and drive shaft still spin, but it is disconnected inside the NP231/NP241 transfer case itself. I think it's possible with the right transfer case to make an H3 have a part time system, but I prefer the extra traction an AWD rig has vs a part time system on the street.
99-04 Jeep Grand Cherokee's with select trac had the NP242 and most Jeep Grand Cherokee owners with Quadratrac II could easily turn their AWD NP247's into a select trac setup with just a linkage/shifter selector swap, and a transfer case swap.
With the part time system you will have less drag, but without hubs the main parts will still be spinning unless you disconnect the front shaft. I owned 2 Jeep 05 Jeep Wranglers and the 04 Grand Cherokee. I never replaced any parts from normal wear and tear. The system seemed to hold up well. I also had 5 Land Rover's with AWD and I never had anything fail either. I did get slack on a transfer case chain, but at 185K that's to be expected on an AWD setup. It worked, but when you let on/off the gas you'd hear the chain slap the case if you did it just right. I sold that Rover and the owner went to 200K before he replaced the chain without any damage.
On Range Rover's and the Quadratrac setup you have a viscous coupling that spins allowing the AWD to function free spin/locking. On the Defender/Discovery/Discovery II the AWD setup was gear driven.
I think it would make the traction control system work harder and brake pad/rotor life would be greatly decreased on our H3's. Everyone with a JK noticed that immediately vs a TJ/LJ. The brake pads especially the rear didn't last nearly as long as the TJ/LJ. Difference being the TJ/LJ didn't have an ABS/TCS setup so the brakes were only being controlled by the driver vs a computer.
The other issue with a part time system is premature engagement or being engaged when being towed or driving on the highway and not knowing the system was engaged. I've seen several TJ's transfer cases EXPLODE so bad that it ripped a gigantic hole thru the floor and destroyed the exhaust, driveshaft, and the dudes pocket book/weekend.
A 97-06 Jeep Wrangler is a part time system without the use of hubs. The axle and drive shaft still spin, but it is disconnected inside the NP231/NP241 transfer case itself. I think it's possible with the right transfer case to make an H3 have a part time system, but I prefer the extra traction an AWD rig has vs a part time system on the street.
99-04 Jeep Grand Cherokee's with select trac had the NP242 and most Jeep Grand Cherokee owners with Quadratrac II could easily turn their AWD NP247's into a select trac setup with just a linkage/shifter selector swap, and a transfer case swap.
With the part time system you will have less drag, but without hubs the main parts will still be spinning unless you disconnect the front shaft. I owned 2 Jeep 05 Jeep Wranglers and the 04 Grand Cherokee. I never replaced any parts from normal wear and tear. The system seemed to hold up well. I also had 5 Land Rover's with AWD and I never had anything fail either. I did get slack on a transfer case chain, but at 185K that's to be expected on an AWD setup. It worked, but when you let on/off the gas you'd hear the chain slap the case if you did it just right. I sold that Rover and the owner went to 200K before he replaced the chain without any damage.
On Range Rover's and the Quadratrac setup you have a viscous coupling that spins allowing the AWD to function free spin/locking. On the Defender/Discovery/Discovery II the AWD setup was gear driven.
I think it would make the traction control system work harder and brake pad/rotor life would be greatly decreased on our H3's. Everyone with a JK noticed that immediately vs a TJ/LJ. The brake pads especially the rear didn't last nearly as long as the TJ/LJ. Difference being the TJ/LJ didn't have an ABS/TCS setup so the brakes were only being controlled by the driver vs a computer.
The other issue with a part time system is premature engagement or being engaged when being towed or driving on the highway and not knowing the system was engaged. I've seen several TJ's transfer cases EXPLODE so bad that it ripped a gigantic hole thru the floor and destroyed the exhaust, driveshaft, and the dudes pocket book/weekend.
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