Hi All,

I recently found out that there's a fuse under the hood that engages the the clutch for the 4wd system. During the last snow storm my truck got stuck and the 4wd wouldn't engage . It was running on 2wd. due to that fuse being blown out. I'll find out the exact fuse and let everyone know..

 

that would be great, so in other words there are two switches that need to be pulled?

 

Aplaza any luck?

 

That's the fuse I pulled and jumped to a switch.

 

If you do install a switch be sure to install it on the load side of the fuse so that your wiring and switch will also be protected along with the 4wd components. It would work either way but If there was a short in the added wire and switch you would want the fuse to blow before your dash catches on fire!!!

 

Not sure how this relates, but I just drove from Virginia to Utah with my 4x4 indicator light flashing on and off. I kept driving after calling two different Ford dealers and speaking to techs who told me that unless it was actually trying to switch into 4x4, the flashing indicated a sensor problem and had defulted to two wheel drive. I drove it around a big parking lot several times in very tight radius turns and it was obvious that the front wheels weren't engaging (the fact that the 4x4 light was flashing even when the tranny was in park was a giveaway too).

When I got to Utah I had a dealer check the codes and he replaced both sensors on the transfer case. He also confirmed that the thing had just defaulted to 2 wheel drive. Interestingly, I was able to switch to 4-high and 4-low and both those modes were available...but when I switched back to A4WD it went back to flashing.

But it seems like a person could put some kind of cutout switch into the sensor circuit and get the 2 wheel drive you are seeking.

 

So I guess if your sensor goes bad for the A4wd, you have the true 2wd.
I have had my switch in line with the fuse for some time now...since winter I think? Whenver this thread started anyway. It works great. When I go up north or it's rainy out, I flick the switch back to factory-mode A4WD. When it's dry out, I'm in 2wd.
Thanks for the info.

 

I'm thinking about doing this mod.......did u notice any gas mileage increase? thanks!

Rick

 

Not really, but I did just get 17.5 MPG on a 460 mile round trip...that's 1mpg better than normal, but due to inaccuracy at pump/full levels on vehicel, it could be a margin of error was on my side.
Mainly just quieter. My front drivetrain would groan a bit in A4wd at low rpm under a load (up-hill). I like it better like this. Plus I can put the hammer down and light up the rears if I get a burst of immaturity!

 

You can light the rears on an Exped? Wow man.

I'm sooooo done with my A4WD...nothing but fits from day one. I'm glad to be rid of my problems...going to wire in a switch and use that 30amp fuse at the dash instead of under the hood. Thanks for all your past work on this.

 

gonna bring back a old thread so after dealing with a little bit of snow this past weekend i wasnt impressed with the A4wd mode in the navi, i would much rather just be in 2wd then switch to 4wd if needed. if i pull the fuse under the hood, can i still select 4x4 hi or i would have to put the fuse back in to engage 4x4? or this is why a switch needs to be wired in to use 4x4? thanks!

 

Yes you would have to put the switch back in.

 

Woops. Meant fuse. . I just keep mine in the glove box with the block # on it so I don't forget where it came out of.

 

I'm not sure I understand the problem.

In the last three weeks I drove to California and back to Virginia.

That included two dreadful snow storms over the Donner pass area going and coming, plus I hit Iowa in time for the Ice storm and Blizzard on I-35 and I-80. My sneakers are still soaked wih diesel fuel from just one of the many overturned semis that I walked in while trying to aid some of the other drivers who got hit or run of the road in one of the multi-vehicle pileups. Dozens of overturned and otherwise crashed semis and I stopped counting cars off the road after I got to 120 on I-80...and there were a lot more after that. But I digress.

On my 99 I only have 3 choices: AWD, 4-high and 4-low.

But unless it senses wheel slippage, the AWD setting IS rear wheel only...it's not full time all wheel drive.

I didn't need 4-low, but I used the other two settings on my trip. When it was really bad and the snow was deeper I used 4-high...but when the traction was better or like in Pennsylvania depending on whether I was going up or down a hill and how high it was...AWD setting was fine since here was snow here and here...but not everywhere.

Why all the bother with taking out fuses and putting in switches? The front wheels only start to turn on their own when there is slippage, and in that case I find it handy...especially when the traction conditions are inconsistent. Frankly I prefer that the two wheel drive get a little help immediately when it gets slippery.

Or do the new trucks have true, full time, all wheel drive? The older ones like mine don't and it seems like a waste of time to switch off the front speed sensors just to avoid a little wheel grabbing when it gets a bit slippery. I have 198,000 miles on my truck at this point...under all sorts of conditions for many years, so I think I have quite a bit of data to base this opinion on. I'm hoping for at least another 50k on this beast.

 

Took mine out because the 4 high was trying to engage around corners. You could smell the thing cooking on dry pavement and feel the resistance in the wheel. Not fully engaged type resistance, but resistance nonetheless. Also our rig is relegated to SoCal now. Kind of retired from snow use. Last, since we purchased it two years ago in CO, the AWD system has never been very responsive. 4 high was always the better option as AWD would kick off too soon. Once that happened we would get an ABS light which seemed to have inactivated the AWD system anyway, forcing us to use 4 high when needed. So maybe a bad ABS sensor/speed sensor is causing my issues with the AWD? Dunno. Pulling a fuse was a cheap quick fix though!