4x4-Brown wire mod question

[GreenSeats]

Will this mod work on my 96 sport that has the 2wd/4x4 auto/4x4 low switch?

my front driveshaft always turns... even with the switch in 2wd, (is this normal?) and I dont think it is helping my gas mileage, not to mention that one of the u joints is squealing.

 

[00XLS]

if you have a 2wd position on your switch i doubt you need to do this mod.

 

[Blee1099]

The brown wire mod is to give 97-01 2WD. Since you have a 95-96, you don't need to do it. If you want to get 4Hi, it will take some work.

 

[GreenSeats]

but... my question is, is it normal for my front driveshaft to turn when in 2wd ?

 

[briwayjones]

Yup, the driveshaft always turns. When it's not in 4WD the Hubs(wheels) aren't connected to the driveshafts so they don't turn.

 

[gijoecam]

As I mentioned in the other thread....

Doing the mod does not stop any of the drivetrain components from turning. It simply stops the transfer case from engaging in auto mode. However.....

.... For the 95-96, there is, what I like to call, the 'Anti-brown-wire mod'. Instead of breaking the wire to disconnect the transfer case, you use that wire to engage the clutch full-time, thereby getting rid of the lousy auto setting and forcing the clutch into full-time 4wd. You wouldn't want to use it full-time on dry pavement, but when off-roading or running in slippery conditions, it could be useful.

-Joe

 

[briwayjones]

.... For the 95-96, there is, what I like to call, the 'Anti-brown-wire mod'. Instead of breaking the wire to disconnect the transfer case, you use that wire to engage the clutch full-time, thereby getting rid of the lousy auto setting and forcing the clutch into full-time 4wd. You wouldn't want to use it full-time on dry pavement, but when off-roading or running in slippery conditions, it could be useful.

-Joe

How do you do that? If you can force it into full 4WD then couldn't you make it so that you could switch between Auto and full 4WD in effect having the same modes that the brown wire mod gives you on newer X's except for 2wd low?

 

[Euch]

i think that mod isn't really worth the hassel, that front driveshaft is always going to turn, the driveshafts between the wheels and diff. are what stops moving when you take it out of 4wd, well unless you have manual lockers then they keep moving untill you unlock em. It's why some people don't like 4x4s they say it sucks up too much gas to turn the front driveshaft, i don't believe it makes that much of a difference. Grease the u-joint and see if that stops the squealing, if you want better gas milage you could always try aluminum driveshafts.

 

[gijoecam]

I'm a bit confused what you're asking...? Help?

 

[briwayjones]

I'm a bit confused what you're asking...? Help?

Who me? I was asking if you can force it into full 4WD then couldn't you put a switch on it so that you can switch between Auto and full 4WD?

 

[gijoecam]

OK, that's what I thought you meant.... It was late and the wording seemed funny to me....

To answer your question, yes, you can. I have mine wired up with a DPDT switch just for proof of concept, even though I already have the ability to lock in 4 high with the OEM setup. Instead of using the switch to break the signal, on the '95-96, you break the wire and apply 12 volts to it to lock in the clutch. I explained it in the infamous "Brown Wire Mod" post in the helpful threads. I'm not sure of the current draw, but it hasn't popped a 10-amp fuse in my playing with it.

-Joe

 

[Bronco638]

...you break the wire and apply 12 volts to it to lock in the clutch....
-Joe

Joe, I think you need to re-read the Brown Wire Mod thread. You cannot simply lock the clutch by applying 12 volts to it. The clutch takes a frequency modulated signal. Otherwise we'd all be ditching the stupid dash switch and making that mod. The Brown Wire Mod basically CUTS power to the clutch which allows the transfer case to be in "2WD Lo."

And, there are no hubs to lock and unlock on a 2nd. Gen. (1995-01) truck. The CV shafts are bolted to the hubs. Everything from the front driveshaft to the wheels/tires spins. The 'disconnect' is the transfer case.

Hope this clears things up - Dave.

 

[gijoecam]

Joe, I think you need to re-read the Brown Wire Mod thread. You cannot simply lock the clutch by applying 12 volts to it. The clutch takes a frequency modulated signal. Otherwise we'd all be ditching the stupid dash switch and making that mod. The Brown Wire Mod basically CUTS power to the clutch which allows the transfer case to be in "2WD Lo."

And, there are no hubs to lock and unlock on a 2nd. Gen. (1995-01) truck. The CV shafts are bolted to the hubs. Everything from the front driveshaft to the wheels/tires spins. The 'disconnect' is the transfer case.

Hope this clears things up - Dave.

I have read most of the twenty-some pages of the brown wire mod thread.... If you read far enough, you'll see that somewhere in the last few pages, I posted this information there a few months back. I highly doubt that anyone manages to get that far anymore. (on a side note, I'd be more than happy to do a complete write-up on BOTH methods to consolidate it)

But I digress.....

Actually, for all the second-gens, the Transfer Case Shift Relay is either on or off. In automatic mode, the GEM varies the DUTY CYCLE . Yes, I know that the light glows dimly the rest of the time, but that's how a solid-state relay works. There's no way to completely turn off the power flow, but the amoutn of juice that flows through it isn't enough to energize the clutch coil. That means that the clutch is still either on or off.

On the '97-'01, when you place the dash switch in the 4hi position, the GEM commands the TCS relay to engage at 100% duty cycle applying a constant 12 volts to the transfer case coil. Seeing as the transfer case function and its internals are the same for all the 2nd gens, there's no reason you can't bypass the GEM and TCS relay all together and manually apply 12 volts to it.

You are correct that the brown wire mod for the '97-01 cuts the power to the transfer case solenoid, giving you 2wd, but that mod got me thinking about the '95-96 and how to give them full-time 4wd. This mod works both ways. My truck is proof. I used one half of the DPDT switch I used to break the brown wire giving me 2wd high and 2wd low at will. I used the other half of the switch in lieu of the OEM switch to manually apply 12 volts to the transfer case clutch and it locks into 4wd. Granted I haven't tried it on a '95 or '96, but it's simply a matter of finding a willing volunteer to confirm my results on the appropriate year. I'm about 99.99% confident it'll work though.

-Joe

 

[Bronco638]

Well, shoot, I would have volunteered for that but it's too late. I have already swapped in the 1354 and sold the 4405.

I'd be nice if you got someone to volunteer their '95-96 to see if your idea works in practice. I'm still convinced the way to go is the manual t-case but that's me. Besides, there's a gain when it comes to swapping cases, the 1354 weighs less than the 4405. I know the 4405 weighs about 80 lbs. I'll bet the 1354 is 20 lbs. lighter.

I think I'M the one that needs to re-read the Bown Wire Mod thread.

D.

 

[gijoecam]

FWIW, I believe that the 1354 may be stronger also, but the major appeal to any hardcore off-roader is that it's manual... no electronics to fail.

For daily driving, I'm quite happy with my Control Trac most of the time. It's just always bugged me that I didn't have complete control over the drivetrain like I wanted. Now, if I could just figure out how to mate up a control-trac with a 4.6 and a manual without throwing the GEM into fits....

-Joe

 

[rmmiller2050]

I am confused yet , guys: I just put my 1995 4405 back together recently , I understood that the front driveline isn't engaged until the electric clutch is energized, as in 4Wauto or 4WLo. In 2WD the clutch pack/chain driving gear assembly rotates freely on the mainshaft until the clutch is energized. If what you say is true that the drive chain /clutch is always engaged and 4WD is accomplished solely by vaccuum engagement of the passenger side drive axle , then what is the point of the electric clutch? I mean why would you spin teh drive chain ( lotsa mass) ,the front drive line /pinion/ring /spiders and DS hub and PS stub axle if you have a freaking clutch that can be totally disengaged during 2WD operation?? Does the front drivetrian always actuate regardless of mode on a 95 control trac 4405 ??

 

[gijoecam]

If you read the 'comprehensive brown wire mod thread' in the list of useful threads, the background information in there might help clear things up a little bit.

In 2WD the clutch pack/chain driving gear assembly rotates freely on the mainshaft until the clutch is energized.

correct.

If what you say is true that the drive chain /clutch is always engaged and 4WD is accomplished solely by vaccuum engagement of the passenger side drive axle , then what is the point of the electric clutch?

Where did we say that? What I have said is that the clutch is either engaged or it's not. In auto mode for all the second-gens, the GEM varies the duty cycle to the TOD relay, which varies the duty cycle to the transfer case clutch coil. In either case, the t-case is either engaged or disengaged.

I mean why would you spin teh drive chain ( lotsa mass) ,the front drive line /pinion/ring /spiders and DS hub and PS stub axle if you have a freaking clutch that can be totally disengaged during 2WD operation?? Does the front drivetrian always actuate regardless of mode on a 95 control trac 4405 ??

not really.... On the 95 and 96, the front axle is equipped with a center-axle disconnect that breaks the passenger side axle shaft in 2wd. When in 2wd, the front halfshafts turn (they're splined to the hubs) but *in theory* the front driveshaft and differential would stop turning, and the spider gears would be spinning away (minimal wear as there's no load on 'em). *In theory* this would save a little bit of wear and tear on the front drivetrain. *In reality* even though the clutch is disconnected in the t-case, there is enough fluid trying to shear between the plates that the front driveshaft *probably* doesn't remain completely stationary. Many of the members with the brown wire mod that have tried to run on a 2wd dyno have discovered that at speeds above 45 mph, the front wheels want to turn. What that tells me is that something is applying some amount of driving force is being transmitted through the clutch, even though it's slectrically disconnected. But how?

I can't say I know for sure, but IMHO, the most logical theory is this: The clutches are still alternating plates, one splined to the input, one to the output. When the front driveshaft is stationary and the rear is turning at a high rate of speed, there trans fluid in the gear case is forced to shear between the two sets of clutch plates. As that fluid shears, (and in extreme cases gets hot and breaks down) that shear force is what forces the front driveshaft to turn. So, Ford said, "The front end parts are still turning, why not eliminate a weak spot and get rid of the center axle disconnect on the front end" and you got the 97 Control-Trac system, with no CAD, 4 auto, 4high, and 4low on the dial. Make sense?

So, I guess the short version to that part is that even though the clutch spins freely on the bench, when it's immersed in fluid, it doesn't spin so free. During 2wd, the clutch and CAD are disengaged. In 4auto, the CAD engages, and the clutch engages as necessary, as determined by the GEM.

Clear as mud, right?

Hope that helps!

-Joe