AW-4 1st gear lock up??

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Mar 3, 2009 | 05:53 PM
  #1  
Ok, I've searched, and still can't find how guys are doing this little trick. I want to be able to keep my XJ in 1st when wheeling in certain situations. Is this possible, or am I just crazy?? I thought I'd seen a write up on this somewhere before, but can't seem to find it now. Any ideas??? Thanks guys!!
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Mar 3, 2009 | 05:57 PM
  #2  
yes

let me look for the info
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Mar 3, 2009 | 05:58 PM
  #3  
Thanks!!
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Mar 3, 2009 | 06:00 PM
  #4  
Try here http://go.jeep-xj.info/HowtoAutoSwitch.htm It gives you an idea of what has do be done...Tj
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Mar 3, 2009 | 06:00 PM
  #5  
Have you done it??
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Mar 3, 2009 | 06:01 PM
  #6  
http://radesignsproducts.com/aboutus.aspx

this is not the sight I wanted but it will give you an idia

I had another sight that gave wire colors
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Mar 3, 2009 | 06:05 PM
  #7  
some diagrams

AW-4 1st gear lock up??-trannyschematic.jpg   AW-4 1st gear lock up??-aw4-switch-box.jpg  

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Mar 3, 2009 | 06:05 PM
  #8  
I haven't done it yet but will be when it gets warmer out...Tj
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Mar 3, 2009 | 06:07 PM
  #9  
OK find the yellow wire coming off the TC
that needs a switch
then you need a second switch to power the #1 solenoid
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Mar 3, 2009 | 06:11 PM
  #10  
Cool, thanks guys!!
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Mar 3, 2009 | 07:14 PM
  #11  
i think BUCK has done it
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Mar 3, 2009 | 07:24 PM
  #12  
Quote: Have you done it??
I have manual 1-auto-2 switch, plus a manual convertor lockup switch - locked 1st, or second as need for hill descent offroad, etc. I was blown away by how well it worked on an icy downhill, off camber section of trail when I first tried it..well, WELL worth the time to do. I now use 3rd locked, instead of the brakes, daily on a long downhill in my morning commute, os its not just an off-road thing, either.

*** I'm nit-picky on stuff like this, and went and found a bunch of OEM Jeep switches to do the install - final result was 2 stock jeep switches mounted to the right of the shifter in the center console. one at the front is 1-auto-2 mode, and the one at the rear is manual convertor lockup ( ANY gear, ANY shifter position) I'll snap a pic, and edit it in later.

edit done - shoot me your email address and I can forward you a copy of the whole how-to that I used to do this ( not my write up, so I dont want to post it complete...)

  

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Mar 3, 2009 | 08:04 PM
  #13  
Neat, I'm going to have to put this in when it warms up.

Related point... what is the effect of downshifting on gas millage? Does putting it in 3 or 2 on downhill stretches reduce the gas millage because the engine is spinning faster, or keep it the same because the throttle isn't actually being opened up any more?
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Mar 3, 2009 | 08:20 PM
  #14  
Quote: Related point... what is the effect of downshifting on gas millage?
no idea - my mileage is good enough that my diesel swap is a tough call. Doesnt seem to have changed from one tank to the next, but I dont go down THAT many hills, so...

oh - found the link to the original writeups: http://www.go.jeep-xj.info/HowtoAutoSwitch.htm read, learn, and you can make the AW4 do pretty much whatever you want.

also: 2 footnotes:
1) I just remembered I hacked one of the swithes: the 1-auto-2 switch is made from an extra rear wiper switch, with the 'intermittent' spring removed from the wash side, and a blank switch face installed ( no light) not hard to do, adn means it'll hold in any of the 3 positions.
2) I DIDNT use a diode on the convertor lockup light...lets me know when its locked whether its in auto, or manual modes. helps TONS on the early XJ's deciding when to be in comfort, or power mode. (Having looked at the pattern of when it locks up, I usually drive around in comfort mode, and use power mode for long grades / mountain driving)
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Mar 4, 2009 | 09:36 AM
  #15  
AW-4 tranny 1st gear lock
Guys, these are all great write ups and really great ways to do this modification but, it can really be done much simpler than any of these.

All you really need to do is cut the yellow wire that goes into Transmission control Unit at pin D16 and put a toggle switch in line with it. That's it. of course, put your toggle switch somewhere it is easy to get to.

In the "ON" position make so the 12V signal is getting there and the tranny functions normally. In the "OFF" position the 12V signal is interupted and doesn't get there. What that does is in effect turns "OFF" the 12V signal going to your TCU. This turns the TCU off and puts your AW4 into a full "MANUAL" mode. The tranny goes straight to whatever gear the shifter is in. So, you just put the tranny selector in "1-2" and go wheeling as it will stay in 1st gear all day. Now, the only bad thing about this is that you have to be careful as, if you put the tranny in "3" or "D" and try to go from a stop. You will burn the $hit out of your tranny because trying to go from a dead stop in 3rd or 4th gear is a big "NO-NO". I fixed this problem by going one step further. I hooked a wire with a red light to the "OFF" terminal on my toggle switch. So, when my tranny is in the "OFF" or "MANUAL" mode my little red light is on to remind me to go back to "ON" or "AUTO" mode before going back to normal driving in a faster part of the trail or on the road.

I hope this helps. I can post pics if you guys want me to.
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