TLDR: My three amigos are on, and only my front wheels are spinning in the mud.

Two nights ago I got called out for work to help out a coworker who was stuck in the mud. He had his International Flatbed DT466 stuck and asked me to help pull him out. I ran two chains from my 2001 discovery2 out to his bumper and started pulling. He asked why only my two front tires were spinning, and I told him to hold his britches and I'll put it in 4 low. I did and still, only the front two wheels were turning. I was confused because I was under the assumption that the truck was all time 4wd. Like I stated in my TLDR, the three amigos are on and even though I'll be getting those fixed this weekend, why were the front wheels spinning when the back two weren't? Would the 4wd system be effected by my TC, ABS & DHD acting up?

 

It is full time 4wd, but not awd. The way it works is that each axle has an open differential, which means that whichever wheel slips gets all the power and the wheel with more traction gets none. The transfer case, which distributes power between the front and the rear, also acts like an open differential. That means that if one or both wheels in the front slip, the rear gets no power, and vice versa. Now, the on board ABS system is designed to counter act the slipping between the left wheels and the right wheels using the brakes meaning that it acts somewhat like a computer controlled limited slip. However, it does nothing for the slippage between the front and the rear. Also, when the 3 amigos are illuminated the ABS system does absolutely nothing. That means, on your truck, if any one of your four wheels loses traction, that wheel gets all the power and the other four simply sit stationary.

 

So I need to get that abs system fixed, and I shouldn't got off road until its working properly. There's a Land Rover salvage yard in Sun Valley C.A. they offered to fix the amigos for $400, which I'm pretty happy about. Thanks for the info, I feel way better about it now. I got the truck for $335 at my tow company auction, its been great so far, just nickle and dime stuff like the instrument cluster light being out, the cup holders were missing. My next big thing is to figure out why my front windows don't work.

 

If it's an early 2001 (VIN sticker would read 6/2001 or earlier)you can add a CDL shifter which will allow you to lock the transfer case making 50% of the power to your front wheels and 50% to your back wheels without having your ABS pump apply the brakes.

I'm guessing the junkyard that's going to do the fix is Elite? They could tell you if you have a locking transfer case and maybe do the shifter install.

 

Or you could fix the Amigos yourself for an hour or two of your time, a $4 part, a soldering iron and solder plus a little heat shrink tubing. And if you want to be really fancy you could add a ring or spade connector for the ground connection. Just search for "Option B bypass" and follow the instructions.

 

Possibly. If that's the actual problem with their ABS, which isn't for sure, but its definitely worth a try.

 

True, but based on traffic I've seen on this and other Rover forums over several years the shuttle valve switch circuit defect seems to be the cause of a high percentage of Three Amigos cases.

I'm usually in the diagnose, diagnose, diagnose camp but if you don't have the right kind of scanner available to you to determine whether or not there is an SVS fault your odds of success are still pretty good, I think.

More importantly for this owner, however, would be to add a mechanism to lock the center diff. With that upgrade you're guaranteed to have a least two wheels spinning!

 

yeah but, thinking a little outside the box, if your 3 amigo's are on and you are stuck with tires spinning... let's hope you have a tool to do a check engine light reset or a codes reset otherwise...

if you can do that, you likely can reset the codes to make them go away and your various systems should re-engage until the pcode causing the 3 amigos comes back again as confirmed codes. That's like 10 minutes or some such.

NOT a recommended long term solution - go find out what your specific code is and laser focus the replacement of parts etc. (i.e. the shuttle valve bypass won't fix a bad hub-mounted ABS sensor).

It likely will get you unstuck tho... pretty sure i've even executed this myself once or twice

either way, worth a try in a stuck situation