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RADesigns Rail Shifter- Install/review-01 xj

srmitchell

NAXJA Forum User
We all know the feeling, when the Asin Warner-4 decides to shift from 2nd, to first gear at the worse time. If you have low gearing like me, it's awful, and it is whiplash inducing in 4 low.

I was tired of this, and I wanted full control of my aw4. Cue the RADesigns rail shifter, and you can get full control of all 4 gears, and with some wiring, full torque converter control.

I used Rory's site, and a couple other sources to find my info.

Big thanks to Rory (Owner of RADesigns) for his help on the phone. He is a NAXJA Supporter, so lets help him out!

http://radesignsproducts.com/aboutus.aspx
http://www.stu-offroad.com/engine/awshift2/awshift2-2.htm

Warning- This mod will trigger the Check engine Light on OBDII Jeeps. I have a code reader/clearer, and I'm not due for smog for 2 years. It does not harm any other systems. It is worth it.

Here's the shifter, next to my key fob for scale.
a2aafe74.jpg


The shifter has 3 wires. Red is 12v power. The yellow and Blue correspond with the 2 different solenoids. Shifting duties are handled by these 2 wires... it's that simple. The rail is just manipulating the solenoids in a way that is more intuitive than toggle switches.

However, I want to have both manual, and auto control. (If someone else drives it, or I'm lazy.)

This switch allows me to decide between the TCU, and the rail shifter.
It is a ON-ON, double pole, double throw switch. I had to order this from NAPA. Part # TG6064. Rory also sells rocker switches and a bezel, but I prefer the toggle design.
5192d125.jpg


In addition to that switch, I wanted full control of the torque converter.
I used a single pole, double throw switch.
The center wire goes to the trans, the red wire is 12v, and the side blue wire is to the TCU.
This way...
-Bottom position, the torque converter is computer controlled.
-Center, TC is off
-Top position, TC is locked. (To be used only during light, cruising loads)
4cb3e28a.jpg


12 Volt duties were spliced into the "key-on" cigarette lighter. It is fused, and only works when the ignition is on.
00036d91.jpg


All wiring was done in pairs, then grouped together. It was confusing, but looks pretty good.
08dc95ba.jpg


Both switches done, and wired to position. I used 3.5 feet lengths of wire for each connection from the tcu harness to the switches. A lot... of... wire. My tcase and shifter bezels are both melted from bad light placement, so those light harnesses are tucked away.
5938f8ec.jpg


It was a PITA to splice all these wires, because the 97+ tcu is tucked above the gas pedal. There's no slack either, so it's easier if you remove the lower knee panels.
3865cc7b.jpg


00-01 Connector pin out- From "stu-offroad", and it is verified correct.
Pin #11- dark blue/white stripe - torque converter
Pin #12 - white - “solenoid A”
Pin #13 - orange/white stripe “solenoid B”

With the console back in, the wires fit well.
04b5d81d.jpg


Switches are near the armrest. I can still fit my sigg water bottle, and the switches are in the right spot for easy finger access.
b3815246.jpg


It's also easy to get to the wires, the center console tray comes right out, with 6 screws.
4fd9e66a.jpg
 
Sweet! I need to do this mod.
 
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And the final mounting location.
I can reach it without leaning forward, no issues.
48fbf96b.jpg


3e76c148.jpg


A word about the function- (From stu-offroad)
Manual Control:
(AW-4 transmission shifter position is noted first in each line)
  • DRIVE position: not true manual control during compression braking as transmission still wants to shift "out". This is just fine as long as you are on level ground (or going up a hill, ledge, etc...) and not descending a steep ledge or grade in low range.​
  • 1 - 2 position: transmission will lock in 1st or 2nd gear and compression braking is now possible.​
  • 3 position: transmission can be shifted between 1st, 2nd and 3rd. Don't expect the transmission to stay in 1st gear​
  • REVERSE: operates normally​

Thanks Guys!

-Columbus
 
Switches are near the armrest. I can still fit my sigg water bottle, and the switches are in the right spot for easy finger access.
b3815246.jpg

That's what she said!!

BTW.. nice write up. I may do this.
But I already have TC lockup switch. Before I swapped to newer console I had it in the shifter bezel so I could engage it with hand on shifter.
I dont want to ruin my my so-nice newer console bezel.. so I think I am going to mount it, and my 2nd gear switch in the blank panel on the right side of the IP of my renix XJ.
I also thought about using the ashtray area, since I do not smoke.
 
Nice write-up with pics. Definitely on my mod short list, but I'm curious about the CEL issue. Does the CEL have to be reset every time after you use the shifter, or will it eventually clear itself after multiple key cycles in normal mode?
 
Nice work!
I don't know how I went so long without one. I mounted my in a different spot than you, but the wiring was very similar except I got my +12V from the keyed TCU input. I agree the only semi-hard part was splicing and soldering underneath the dash because of the confined space.

RailShiter2.jpg
 
Thanks guys.

I imagine that after a period of time without using the shifter, the cel would clear.
With the switch down, wiring it the same as stock.

RCman- I considered the same spot, but it's too hard to use the e brake. Nice install though.

I highly recommend this mod, because you can still drive it like stock.
 
If you feel like fooling around with the electronics, raniel and Kastein got a system working that won't throw a check engine light most of the time. You can integrate their system with the radesign shifter. I'd like to see someone try it. Here's the thread where they worked it out:
http://www.naxja.org/forum/showthread.php?t=1034635

For anybody who can't have the light on,(for emissions reasons, or if it just bothers you) check out the montana fab shifter.
http://www.naxja.org/forum/showthread.php?t=1010278 It's kinda expensive, but the latest system is literally plug-n-play.
 
That's really cool. I really don't understand resistors however, and I wouldnt know which to choose, and where to wire.
 
That's really cool. I really don't understand resistors however, and I wouldnt know which to choose, and where to wire.

From looking at their post... my understanding its to let the TCU drive a dummy load so it dosn't freak out about sending voltage to the solenoids and then there being no current draw. Then they had some issues with the it out smarting them when the tcu wants to be in a gear the resistor says there's a load, but then the throttle position or rpm or something else lets it know that it isn't the case. Or something.

Its a good read on reverse engineering the system.


Anyways, Nice well written post. I want to get one of those shifters soon here for my renix.

How's the shifter for everyday use?


A word about the function- (From stu-offroad)
Manual Control:
(AW-4 transmission shifter position is noted first in each line)

*
DRIVE position: not true manual control during compression braking as transmission still wants to shift "out". This is just fine as long as you are on level ground (or going up a hill, ledge, etc...) and not descending a steep ledge or grade in low range.
*
1 - 2 position: transmission will lock in 1st or 2nd gear and compression braking is now possible.
*
3 position: transmission can be shifted between 1st, 2nd and 3rd. Don't expect the transmission to stay in 1st gear
*
REVERSE: operates normally

Any input on what "Don't expect the transmission to stay in 1st gear" OR "...as transmission still wants to shift "out"" means?
 
Got it. That makes sense.

The shifter is fun, however it's not something I want to use 100% of the time. The biggest benefit is in low range. 2nd gear starts are cool. I kinda feel like the tcu shifts better and at better times that I can, so when I'm trying to accelerate quickly, leaving it stock seems best. All I need to do is improve my technique.

Also- locking the TC in 2nd, 3rd, and 4th when I want it great. My gearing is low enough that I can comfortably cruise on level ground, in 4th gear with a locked tc, at 35 mph. RPM's stay low, mpg's go up. I use the TC like a clutch. You have to turn it off when you shift.

However- My tcu just stopped working.
2-3 years ago, I shorted my stock one out. This one is from a junkyard. (Hence why it says "00, JW..." in yellow pen.) I tried to manipulate one of the solenoids, and one of the switches touched a ground... voila, dead tcu.

Today- there are still 2 butt connectors from that old splice, and I believe the wires are loose, hence why the tcu suddenly stopped. I'll check the wiring. I went down a bumpy dirt road. These loose wires are not because of my wiring and shifter yesterday, it was probably because of me stretching, and moving the TCU harness.

"Any input on what "Don't expect the transmission to stay in 1st gear" OR "...as transmission still wants to shift "out"" means?"
-When the jeep shifter is in D, you have no control over engine braking, just the 1-4 control for acceleration. In order to obtain engine braking, in 3rd, 2nd, and 1st, you most move the factory shifter to the correct gear. (3, or the 1-2 split)

To choose 1st, or hold 2nd on a downhill- I like to turn the rail shifter on, choose 2nd gear on the rail, THEN shift to 1-2 on the jeep shifter. You then have full control of 1-2 gear, as a means to slow down.

It seems very complicated, but I've only driven it 10 or so miles, and it's totally second nature.
 
Yes, holding you back is done with a combo of both shifters. It doesn't actually shift up it just free wheels basically unless you have the shifter in 1-2 for 1st or 2nd, in D you have compression braking in 2nd and 3rd, in OD comression braking in 3rd and 4th.. Just like the stock TCU tends to do.
 
So all the wiring is fixed.

It looks like the TCU goes into limp mode if you switch in and out of the rail shifter more than 2 times.

So if you start stock- (TCU)
Tcu>Rail Shifter>Tcu> Rail Shifter> TCU- the 3rd time you go stock, the tcu stops working. This is ok, because all you need to do is shut the key off, then restart, and it works.

All this means is that you can't freely switch in and out of stock/rail shifter. Decide how you want to drive it, and leave it. Until I figure out a resistor setup, this is how it stays.

Overall, it works great, and for the Jeep enthusiast (more attentive than the average driver), it is easy to use, and live with.
 
Clean install.

I've been wanting to do this since I got my XJ.... which is only a couple months ago, haha

So all the wiring is fixed.

It looks like the TCU goes into limp mode if you switch in and out of the rail shifter more than 2 times.

So if you start stock- (TCU)
Tcu>Rail Shifter>Tcu> Rail Shifter> TCU- the 3rd time you go stock, the tcu stops working. This is ok, because all you need to do is shut the key off, then restart, and it works.

Do you think this is a problem associated with the later XJs only? Or would I run into the same problem if I installed this onto my 89?
 
It looks like the TCU goes into limp mode if you switch in and out of the rail shifter more than 2 times.

So if you start stock- (TCU)
Tcu>Rail Shifter>Tcu> Rail Shifter> TCU- the 3rd time you go stock, the tcu stops working. This is ok, because all you need to do is shut the key off, then restart, and it works.

All this means is that you can't freely switch in and out of stock/rail shifter. Decide how you want to drive it, and leave it. Until I figure out a resistor setup, this is how it stays.
I noticed this as well, but it does not seem to do it to me if I have the shifter in neutral when shifting between TCU and Rail control. Either way it isn't the end of the world to re-key start if it happens. 1st time it did it I was a bit concerned though.
 
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Do you think this is a problem associated with the later XJs only? Or would I run into the same problem if I installed this onto my 89?
It'll be a problem for anything from '96 to '01. Those are the ones with the TCU that talks to the ECU.Everything '95- down are cool with any switching setup you care to use.
 
Update on the shifter-

It's really great off road. I used it in the sand dunes, and having 2nd gear is awesome.

Bottom line though... It doesn't work well on the street. (For my 2001)

The TCU knows you're f-ing with it, and goes into limp mode everytime. (No shifting, Drive position yields 4th gear, which means you go nowhere.)

Basically, if I decide to shift using the rail, the TCU will no longer work correctly. I can't switch between the rail and stock function, using my over ride switch. If I use the rail to hold 2nd, I have to shift the rest of my drive. (It only goes out of limp mode when you shut the motor off.)

Verdict
-The 97+ doesn't work as easily. I can't "hold 2nd" then go back to stock function. I have to shift gears, and fiddle with over drive. (My gearing is low, If the lockup doesn't work, I tach 2800 rpm+ at 65, and mpg goes down) I found that I can't shift, turn on overdrive, accelerate, turn off overdrive, and then shift as quickly, or efficiently as the TCu. (Obviously) City mpg goes down about 4 when I use the rail.

-Off road, it's really fun. However, same issue. I was using the rail in the dues, then I decided to go fast on the beach. I had to fiddle with the overdrive, because reving in 4th gear, 4low and no OD= Excessive transmission temps. I shut the engine off, and restarted so I could get the TCU to work again.

As much as I love the system, I still want to swap a 5 speed.

87-95 xj owners, you will not have this issue.
 
Have you tried putting it in neutral before you switch back and forth between the TCU and Rail? On my '97 this works well and I can switch between them a seemingly infinite amount of times and no limp mode. Of course I almost never use the TCU control anymore anyway.

Either way I still see it as a very minor issue for how great it works otherwise.
 
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