'96 up Auto trans gear control: Montana Fab

[kastein]

Yeah, I think I said something about that a few pages back... not sure. Most of the info I posted in here was stuff about the stock TCU, with some stuff about the montana fab kit as well, including some blind guessing about its functioning I did before looking at anything more than the picture on their site, which turned out to be mostly correct.

If/when I do one - first thing, I won't be posting anything specific about its design till I have the parts on order and the PCB artwork sent off for fabrication (at which point it'll be released open source under a license I still need to determine.) Second, my name will probably be in blue before I do that (if I do.) It'll show up in product development most likely.

Again... really not trying to step on any toes here. I think they have done a great job (and I have absolutely no intention of intruding on their O2 sensor simulator product line, they've done a great job of covering that market and I don't see any way I could improve on their products) but I think there are some people out there who don't have all their desires/needs covered by their kit, or who don't need something that advanced/full-featured.

 

[xj_mike]

Well, after finally getting frustrated enough with the damn 1-2 shifts (not staying in the gear I want) I went ahead and ordered one from Montana Fab today. Really nice guy on the phone. Should have it early next week. Can't wait to finally have control over the gears. No idea what the hell Jeep was thinking not giving us full manual control over all the gears.

I'll post up my opinions once I get it and install.

 

[97XJ2]

Excellent, waiting to do this myself.

 

[xj_mike]

I received the package this week and wanted to get this installed before my next trip coming up. One very noteworthy change from the OP install it is now almost 100% plug and play. You only have to splice 1 wire for the illumination (if you didn't want it to light up, you could not even have to splice anything). The longest part is mounting the switch setup. I decided to put mine down by the 4WD shift lever. It makes it really easy to switch but out of the way. I don't have to reach past the steering wheel either. The install went so quickly I only snapped a few shots of the mounting. Completely forgot to get one of the control unit.

Here is a pic from there site. You unplug the factory harness, plug it into the Montana unit and plug their plug into the stock unit. Double sided tape and you are done. Cake!!!

Here is where I decided to mount my switch

After using the supplied template, drilled the holes and mounted the face. It is a black mylar sticker on an aluminum plate and the LED make the numbers glow green (white when lights off)

Switch and knob mounted and everything back in place. I tapped the illumination wire from the 4WD light harness

As for driving with it... I can honestly say it is the best $150 I have spent on the Jeep in a very long time. It works perfectly, allowing it to hold 1st or 2nd as I want. One thing to note, if you have the gear selector in 3 or OD and select 2 or 1 on the switch, it does not send fluid thru the tranny to allow engine braking. It allows it to "free wheel" if you don't apply gas. This helps if you accidently switch into the manual mode going too fast. As long as your foot is off the gas, the RPM's will drop and not over-rev.

If you select the 1/2 gear selection, the tranny works just like it would in either gear but now you can hold it in 1st or 2nd. This is great!!!!

No codes have been thrown and I was playing with it a lot on my test drive. This is on a 2000 model.

Also, should you have a problem with the Montana Fab unit, you can just unplug it and put everything back to stock in a matter of minutes. If you have been thinking about this, pony up the $$$ and you will be ever so happy!

 

[casm]

I'm not reverse engineering their product - I'm reverse engineering the stock TCU in an attempt to underbid and outperform them. If I end up building something and selling it here (as a vendor of course) it will have more functionality.

Just exhuming this thread to see if you made any progress with the stock TCU - I'm thinking of putting a manual shifter kit on the list for this year's mods, but am waiting to see what else might crop up. I like the Montanafab kit for its plug & play approach, but have this nagging feeling that it's not quite exactly what I'm looking for featurewise.

 

[kastein]

Work schedule's been hell recently - I've been doing ~60-70 hour weeks for some time. I got a good percentage of the discrete components removed from the board and checked their values but have not done much other than that. No idea when it'll be ready, honestly.

 

[casm]

Work schedule's been hell recently - I've been doing ~60-70 hour weeks for some time. I got a good percentage of the discrete components removed from the board and checked their values but have not done much other than that. No idea when it'll be ready, honestly.

That's cool; was just curious and totally understand how it goes. As an aside, I don't know if you've got any interest in looking at the ECU, but it's something I've been curious about for quite some time now - but I've been in the same work/time boat until recently.

 

[xj_mike]

Had my first outting with this and I am very happy with the results. I finally had a way to keep it in 2nd gear and not drop into 1st when I needed to slow down a little but not enough to need first.

Actually I found that I would leave the shifter in 3rd and use the switch to manually control my shifting. A nice side benefit is when held in second, the converter would lock up allowing the tranny temps to stay low. Since I run in 2nd a lot (having the trailer behind me) the lock up was great. I never got a tranny temp over 210* (output temp) where prior it would sometimes get up to 260* Most of the time it stayed near 190* and that is mainly crawling along.

Also, the plug and play connections allowed me to bypass the controller after I had thrown a code. I wasn't sure what the code was for and thought I would bypass it and put things back to stock. As it was, it had nothing to do with the controller and was a misfire #4 cyl. code. It was a heat soak issue.

The Montana Fab unit might not be for everyone but it is exactly what I wanted and needed. YMMV

 

[casm]

Actually I found that I would leave the shifter in 3rd and use the switch to manually control my shifting.

That actually clears up one of my questions regarding how it works in day-to-day operation, and makes a lot of sense. I pretty much never have my XJ in Drive on the trail anyway, so this sounds very workable.

A nice side benefit is when held in second, the converter would lock up allowing the tranny temps to stay low. Since I run in 2nd a lot (having the trailer behind me) the lock up was great. I never got a tranny temp over 210* (output temp) where prior it would sometimes get up to 260* Most of the time it stayed near 190* and that is mainly crawling along.

Very nice. I'd like fully-manual control over the converter, but that's a reasonable tradeoff.

The Montana Fab unit might not be for everyone but it is exactly what I wanted and needed. YMMV

Yeah, it's definitely sounding more suitable. My gut feeling is that I'd prefer pushbutton control over the gear selection, but from your description the dial sounds workable in practice. Thanks!

 

[xj_mike]

I actually found having it in the center console, I was able to switch it without ever looking. Dash mount is more visiable but I didn't want to have to reach past the steering wheel to switch it.

I agree, a full manual control of the lock up would be nice but this is a good method.

One side note, if you have the shifter in 3rd or 4th but move the switch to 2 or 1, you do not get engine braking because of how the fluid is routed internally due to the selector shaft. Put it into the 1/2 slot and engine braking works like normal in whichever gear you select.

I found I liked not having the engine braking on level or uphill as the trailer drag did enough of that. On downhill sections, I would just drop it into the 1/2 slot and got the needed braking. Just wanted to make sure that was clear.

 

[casm]

I actually found having it in the center console, I was able to switch it without ever looking. Dash mount is more visiable but I didn't want to have to reach past the steering wheel to switch it.

Yep, the mounting location is something I'll have to figure out - but I like the way you used the blank space behind the transfer case lever next to the handbrake. I was thinking of Dremeling out a hole for it in the blank space on the gear lever bezel, but I'm not sure that either a) there's suitable space in there to mount the dial, or b) that I want to reach that far to have to work it.

One side note, if you have the shifter in 3rd or 4th but move the switch to 2 or 1, you do not get engine braking because of how the fluid is routed internally due to the selector shaft. Put it into the 1/2 slot and engine braking works like normal in whichever gear you select.

OK, that clears that up. Much appreciated.

I found I liked not having the engine braking on level or uphill as the trailer drag did enough of that. On downhill sections, I would just drop it into the 1/2 slot and got the needed braking. Just wanted to make sure that was clear.

Right, and I can see where that would be advantageous when towing. Out of curiosity, how does that affect transmission temperatures? I'm not clear on whether or not that's lowering the fluid flow rate to the cooler.

 

[xj_mike]

I noted no changes in tranny temps and again was quite surprise to not see any temp reach over 210*, which has never happened on any outting since having the gauge.

 

[tbburg]

Long term update:
Still works great.

One thing to think about if you're contemplating this. Working on another project,(sat radio install) I discovered a minor annoyance. With the shift controller mounted on the dash cover, it makes it a pain to remove the dash cover. Because the control harness is soldered to the controller, the only way to remove the dash cover is to dismount the controller and let it hang loose while you're working.

Something to think about if you're one of those people that has the dash apart every couple weeks.

 

[casm]

Exhuming this thread to figure out a couple of things before pulling the trigger on an order.

Long term update:
Still works great.

Glad to hear it; I've put this onto the 'will happen' list for the next round of upgrades.

Something I'm curious about: how has the rotary switch proved to be just in terms of living with it? It looks perfectly functional, but if you could let me know how it works out in practice it'd be appreciated.

One idea I did have was to replace the rotary switch with a 3-position rocker - use the middle position for normal operation, and assign first and second to the outer switch positions. Looking at how the kit goes together, though, the switch actuator appears to be surface-mounted to the PCB, so some light soldering would be involved.

 

[kastein]

The switch isn't surface mounted (at least in the edition tbburg installed, I haven't looked at the latest improvement they've done) - that ring of solder joints on the back of the board is its terminals. It's just a Grayhill-manufactured rotary switch, 4P3T, so if you can find a slide switch that has that contact configuration you can solder it in after ringing out the stock switch. I don't know if it's a break before make, or make before break switch though.

 

[xj_mike]

So far I haven't had any issues with the rotory switch... now my brain, that's a different story. Have forgotten that I had it in the 1 position and then wonder why it won't upshift. Doh! Put it back in D and everything is okay. About the only disadvantage of not having it on the dash, it's not glaring at you to see what position it's in. Advantage of being in the center console is I don't have to remove it if I need to pull the dash.

Also, IIRC, the latest generation (which I believe is the one I have), the switch assembly has a connector on the wires to allow it to be disconnected from the control box.

 

[casm]

The switch isn't surface mounted (at least in the edition tbburg installed, I haven't looked at the latest improvement they've done) - that ring of solder joints on the back of the board is its terminals. It's just a Grayhill-manufactured rotary switch, 4P3T, so if you can find a slide switch that has that contact configuration you can solder it in after ringing out the stock switch. I don't know if it's a break before make, or make before break switch though.

Awesome info, thanks. That tells me it's feasible to remote-mount whatever switch is used from the PCB; more on why I'm interested in that approach below.

So far I haven't had any issues with the rotory switch... now my brain, that's a different story. Have forgotten that I had it in the 1 position and then wonder why it won't upshift. Doh! Put it back in D and everything is okay. About the only disadvantage of not having it on the dash, it's not glaring at you to see what position it's in. Advantage of being in the center console is I don't have to remove it if I need to pull the dash.

Excellent, and also good to know. These are all reasons that come back to why (in a large part) I want to remote-mount the switch. Further to that:

Also, IIRC, the latest generation (which I believe is the one I have), the switch assembly has a connector on the wires to allow it to be disconnected from the control box.

Where possible, I like to cluster switches close to the things that they operate. With respect to the Montanafab shifter, my idea was to mount it in the blank space on the gear shifter bezel to the right of the shifter lever - the killer was if the PCB would also fit behind the bezel, which didn't seem likely. Between what both you and Kastein have mentioned here, that now seems completely doable.

Thanks, guys :cheers:

 

[anthrax323]

Where possible, I like to cluster switches close to the things that they operate. With respect to the Montanafab shifter, my idea was to mount it in the blank space on the gear shifter bezel to the right of the shifter lever - the killer was if the PCB would also fit behind the bezel, which didn't seem likely. Between what both you and Kastein have mentioned here, that now seems completely doable.

Thanks, guys :cheers:

My 1-2 override controller just arrived yesterday, and I was thinking about this spot as well... I popped the shifter bezel off my 2001 a little while ago and found plenty of room for the PCB to hide behind it so long as you don't mount it too far back... Aiming for the exact center of the blank space should allow a perfect fit.

My unit is also the latest revision, so it is 100% plug-and-play with the exception of the interior lighting lead. I'm hoping to get it installed tomorrow and will try to take some pictures to add more info to this thread.

Another bonus of using the shifter bezel as the mounting location would be the irreversible modification of a relatively small and easily replaceable interior piece... I was originally planning on mounting it just in front of the T-case shifter or under the E-brake lever, but this seems like it'll be more ideal, not to mention easier.

 

[tbburg]

Sorry CASM,... 'Wasn't ignoring you, just didn't realize there had been an update.

I was leery of the rotary switch when I first saw the unit, but in use it's working out just fine. The biggest question I had with the rotary was how hard it would be to use it and hit the "2nd" position without overshooting. In use, it's not a problem. I don't think a toggle switch would be any easier.

Like XJ-Mike, I've had the occasional dumba** attack(even with it mounted on the dash in front of me). Unlike him, I tend to leave it in second. I don't use it for 1st much, as the trans defaults to 1st, and I don't romp hard enough to have a problem with it inadvertently up-shifting.

'Like the "plug and play" harness on the newer version. That's a great idea.

 

[austinaubinoe]

wow I think I may buy one of these aswell. Was looking at those manual shifter things, but those seem way to complicated for me. I just want to keep my AW-4 in first gear for the low ratio, this seems like it would perfect. The fact that it is plug and play make it even better!