I did this hack for the second time last weekend and had to look back in previous posts to see how this hack was done (the last posts were about six months ago) I found the posts but had a real hard time figuring it out because of all the technical mumbo jumbo going on at the time. I thought I'd re-write this simple procedure for others to see.
This hack lets you engage the rear diff lok at anytime, 2 hi, 4 hi or 4 lo, at any speed the vehicle is going. As an added benefit, when you engage the diff lok you disable traction control, VSC, and ABS brakes (well, disabling the ABS is of no benefit but no loss either cause you should be off road in mud or sand or something)
Here's how it's done.
Remove the foot rest and kick-panel on drivers side. Locate blue box (diff lok control module) Remove single bolt holding it in place and unplug harness. Fish harness around other harnesses so you have some wire to work with. Locate the white wire with a blue stripe(don't get confused, there is also a blue wire with a white stripe, don't touch this one) Cut the white wire with a blue stripe leaving enough wire to re-connect later should you want to. Tape up the end that goes into the harness. Add a small length of wire to the plug side with an eye at the end. This will go under module attaching bolt on re-assembly. Locate purple wire with a red stripe. Cut and tape both ends, this is the speed control wire. Re-assemble with white with a blue stripe wire grounded out under mounting bolt. That's it. To use, just press the rear diff lok button and have fun. It's pretty cool seeing two rooster tails behind you as you floor it through a muddy field in two wheel hi (with the farmers permission of course). Donuts are a blast too.
Just to clarify a little when he says "at any speed the vehicle is going" this does not mean you can turn it on at any speed(that would be bad) but rather you can go as fast as you want with it engaged. You must be going <5mph to turn it on I prefer to stop.
I did this hack for the second time last weekend and had to look back in previous posts to see how this hack was done (the last posts were about six months ago) I found the posts but had a real hard time figuring it out because of all the technical mumbo jumbo going on at the time. I thought I'd re-write this simple procedure for others to see.
This hack lets you engage the rear diff lok at anytime, 2 hi, 4 hi or 4 lo, at any speed the vehicle is going. As an added benefit, when you engage the diff lok you disable traction control, VSC, and ABS brakes (well, disabling the ABS is of no benefit but no loss either cause you should be off road in mud or sand or something)
Well actually there is a benifit to disabling ABS especially in Sand or Loose Dirts because it allows you to build up a mound of soil to stop the vehicle faster
according to the manual, the locker will automatically disengage after 30mph. don't know how true this is, but it seems like the hack is to bypass this feature - not specifically for which speed it engages.
I was wondering is there any way to have a hack like this, but have it where it is on a separate switch and it resets every-time the you turn off the key.
My wife drives this FJC most everyday and I would not want her to accidently turn it on, or have me somehow leave it on.
Good idea...
I had my FJ washed and the guy who did it hit the button on accident turning the locker on, he drove it this way back to my parking spot. It was only about 50' so it wasn't to bad. But it is definitely something you need to keep your eye on if some one drives your FJ.
I am sure you could run it thru a switch I would have to look at it closer though.
i read up on this mod a lot a couple months ago and dont recall anything about the purple wire with red stripe being cut. Is this a new find that does something good?
I don't see any reason to turn it on at 60 mph either but the point is that you can and there is no problem. You seriously cannot tell that it is on or off at that speed. There are times, however, say at 20 mph where you want to have a bit of fun and you can just press the button and go. Beats coming to a complete stop before you can engage it.
Perfect & simple! I done & it works perfectly! Its nice being able to have that kind of control of your locker depending on your offroad driving needs!
This would be perfect for the sand too. Its just a poor mistake on Toyotas part not to have installed a traction control switch just so we don't look like fools driving around on a beach in 2wd and getting stuck!
Honestly, I don't think you'd break it by going 100 mph and engaging the locker. If you're on pavement and going basically straight-ish, the axle shafts are going at about the same rate. Having the mechanism slide over at speed doesn't seem like it would be much different than if both axle shafts were stopped... as long as they're maintaining a relative alignment.
However, if you were on wet pavement, and were revving up for a drag race burnout, and you cut loose and got ONE REAR WHEEL SPINNING... and THEN popped the switch... you'd probably eat the splines off of the mechanism.
I suppose this would also hold for a 100 mph tight turn. Any situation where the differential is actively in use to let the shafts be driven at different rates would be dangerous for the mechanism to engage into.
Of course, the FJC isn't in danger of accidently being involved in any 100 mph tight turns.
In HI LOCK it should be like it is in LO LOCK. In 4 HI the transfer case is like an open differential between the front and rear driveshafts which means that any one wheel can spin and can cause loss of traction. Locking the rear diff. will mean that you will either spin both rear tires or one of the front ones. You will gain a small amount of traction but not near as much as our AT. The main benefit will be the turning off of the traction, vsc and abs controls. You should still be able to increase the fun factor with this mod. Perhaps someone has tried this on their MT FJ and can comment with authority.
I have discovered something new with this mod that may be helpful from time to time. With the 35 inch tires I'm running, I find that the traction control seems to be more sensitive and the ABS is less sensitive. I have found myself going sideways a few times with the ABS still turned on. If I wait until the truck is going faster than 40 mph and then turn on the rear diff lok, after 5-10 secs the VSC TRAC light will come on. You can now turn off the rear diff lok and release the differential and still have the traction, vsc or abs controls disabled. The only problem is that you have to restart the engine to clear the lights and re-enable the controls again.
Blinking generally means it's armed to come on but hasn't yet. It seems to come on when it likes, I've found that's usually rolling at a very slow speed. The light should be solid though when it's locked.
it says in the manual, and it works in real life, when you turn on the rear locker and it doesn't engage right away try turning the wheel slightly left or right. while going very slowly.
I was going to do this Hack tomorrow, with a switch!
But I have a question:
You said this hack disables Trac, VSC and ABS.
I would like to have the ability to have the Rear Locker In 4 High and leave the TRAC working. As stock, the FJC, in 4 high does not have VSC but does have TRAC.
I shot some video in 4 high in deep sand and I could see both front tires digging and spinning.
I did a quick test and got side straddled, 2 diagonal wheels off the ground, in 4 low without A-Trac or Rear Locker and I would just spin the free two tires.
I put into 4 high and I could here the familiar brake chunking and the FJC pulled itself off the side straddle.
I would think that would be another great ability to be in 4 high and have Trac working up front and the Rear Locked! Is there a way to do this?
Interesting thought, I took a quick look at the schematic and there might be a way to do this. Do the diff lock hack as per usual. Insert switch in blue wire with yellow stripe that goes into Skid Control ECU. Rear diff lock should engage but the ECU wouldn't see it therefore keeping the electronic gadgetry still working. I can't think of any problems off hand. The wire does run thru connector LA2 which is behind the drivers side kick panel. Let us know how it works out.
Sweet!!! You guys keep testing this high speed diff engagement thingy. I need some more spare parts. A totalled FJ or two would come in handy around the house. After you blow the side of you carrier off while going 60+ mph and engaging the e-locker you'll be glad VSC and ABS are off.
Sweet!!! You guys keep testing this high speed diff engagement thingy. I need some more spare parts. A totalled FJ or two would come in handy around the house. After you blow the side of you carrier off while going 60+ mph and engaging the e-locker you'll be glad VSC and ABS are off.
My lights don't come on, just the blinking locker light. I think I'll put it back to stock. The last thing I want is my FJ sitting in Scully's backyard!
You are correct that there is a fork that moves a sleeve to lock one axle to the differential case similar to a transmission shift fork. As soon as the vehicle starts to move the fork sees the rotational movement of the sleeve regardless of whether it is engaged or not. The mechanism is spring loaded so that as soon as you get some differential action, it clicks in. It is only when there is differential action that there is any difference is speed between the collar and the differential case. The only time the fork has any pressure on it is when it is trying to engage or disengage(red light flashing). This is only for a short time. It is running is gear oil. Transmission shift forks seldom wear out even when people drive with their hand on the shifter putting pressure on it all the time. Load and speed don't come into play with the mechanism itself as far as I can tell(as long as wheels aren't spinning). Locking the axles kinda defeats have traction control etc. which why Toyota defeats all of these functions when the locker is engaged. This is why you are only supposed to be able to use it in 4 LO. The only mechanical reason for not engaging it at speed is because of the spinning wheel engagement. IMHO.
I may not have been around for a while on this forum but I have been around for quite a while. I have made a living repairing vehicles etc. for nearly 30 years. I know that doesn't necessarily mean I know what I'm talking about but I do have a reputation of being one of the best techs in this area. Yes, we are all entitled to our opinions, but the way they are presented is what makes the difference. This is great mod (IMHO) and your comment plus others that are not based on fact, might scare people away from doing it. I have over 13,000 miles on my rig now and use the diff lock regularly and no problems so far. It sounds like there are lots of others out there too that have done it with no reported problems related to the hack. I would be the first to post something if anything negative showed up with this hack.
I made several statements in my post, which ones specifically arent based on facts???
Are you really comparing shift rails in a transmission to engaging an electrically operated diff that has been hacked???
Look, again I am not trying to say the hack is a bad idea I am simply voicing my opinion about engaging the diff at speed!!!
At the end of the day I feel like you are going to argue with me until I stop replying. Your opinion is that engaging the diff at speed is okay, my opinion is that it is not okay to do that.
......In case you think Tim is just a charming, well-spoken naturist and nice, fun guy. Here's a little about him from the Toyota site. Now I know it makes him sound like a rank "shade-treer", but let's at least give him the benefit of the doubt.
Tim Scully is one of those guys who has mud running through his veins. A Certified ASE Master Technician and off-roading enthusiast, nothing comes more naturally than inching over a trail.
Trail-tested: 2006 FJ Cruiser Trail Teams Lead Driver
• Crawford's Fall Crawl 2002, Tellico, NC, champion • East Coast Rock Crawling Championship 2002, champion • Land Rover TreK 2000, White Sulphur Springs, W.VA, champion • Land Rover Global TreK 2001, South Africa, third place • Certified ASE Master Technician since 1998 • Land Rover University, training in engine management, electrical, diagnostics, drivelines, and steering
Please realize all the advice you find on the internet forums is free. Proceed with caution
Tim, I'm PMing my address so you can mail the check now.
Tim, the discussion we have had in the last few posts is what this site is all about. I have no problem if your opinion is different from mine. My point is that specific concerns thrown out for discussion are great, comments like
Sweet!!! You guys keep testing this high speed diff engagement thingy. I need some more spare parts. A totalled FJ or two would come in handy around the house. After you blow the side of you carrier off while going 60+ mph and engaging the e-locker you'll be glad VSC and ABS are off.
with no reason as to why are meaningless and detrimental. The other thing to keep in mind with the hack is that when I say "engage at speed" I am usually going 10-20 mph. I just mind it a PITA to come to stop before being able to engage it. The other thing is that the conditions up here are way different from what you see and vice versa. I tend to forget that too. We have had snow on the ground for a month now and have just got 2 feet in 2 days. I just wish that I didn't have to spend all my time cleaning it up instead of wheeling in it
Tim, the discussion we have had in the last few posts is what this site is all about. I have no problem if your opinion is different from mine. My point is that specific concerns thrown out for discussion are great, comments like with no reason as to why are meaningless and detrimental. The other thing to keep in mind with the hack is that when I say "engage at speed" I am usually going 10-20 mph. I just mind it a PITA to come to stop before being able to engage it. The other thing is that the conditions up here are way different from what you see and vice versa. I tend to forget that too. We have had snow on the ground for a month now and have just got 2 feet in 2 days. I just wish that I didn't have to spend all my time cleaning it up instead of wheeling in it
His meaninless and detrimental statement is not nearly as damaging to a novice as your "engage at speed" statements.
Good thing Rover stamped the disclaimer
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