FAQ Discussion: Crawl, Multi-Terrain, Optional Lockers or ATRAC when best to use each

[kcjaz]

I'm new to my 200 and it has been 15 years since I sold by FJ60 (a tragic and long story). I am also new to this forum and it is a gold mine. As I have been playing with my new toy, I have been wondering about how to best use the crawl feature. This thread has answered a lot of questions. Thanks guys. I am still thinking I want air lockers though... Actually, what would happen with a locked rear diff if you tried to to put crawl or turn assist on? I'm thinking nothing good.

 

[Romer]

If both front and Rear lockers are engaged multi-terrain wouldn't do anything.

Its best not to use your front locker much, overuse of the front locker causes breakage. I only turn it on while I am driving straight over something that didnt work without it and turn it off the second I get over it. Look in the FAQ thread and review the Diffs for Dummies thread to understand the stress on the front when you are turning and locked

However, since the rear wheels are never turning from each other, you can use those more frequently. In that case, the rear would be locked and the multi-terrain, Crawl would be applying brakes on the front so there is benefit there

I don't think the multi-terrain works with the center diff locked (Tcae not front or rear diffs), but Crawl mode does. That would still be useful with the rear locked and possibly even the front

 

[kreiten]

If both front and Rear lockers are engaged multi-terrain wouldn't do anything.

Its best not to use your front locker much, overuse of the front locker causes breakage. I only turn it on while I am driving straight over something that didnt work without it and turn it off the second I get over it. Look in the FAQ thread and review the Diffs for Dummies thread to understand the stress on the front when you are turning and locked

However, since the rear wheels are never turning from each other, you can use those more frequently. In that case, the rear would be locked and the multi-terrain, Crawl would be applying brakes on the front so there is benefit there

I don't think the multi-terrain works with the center diff locked (Tcae not front or rear diffs), but Crawl mode does. That would still be useful with the rear locked and possibly even the front

Romer is spot on with this, well said! One quick exception, you can lock the center diff while using the multi-terrain feature!

 

[Romer]

Romer is spot on with this, well said! One quick exception, you can lock the center diff while using the multi-terrain feature!

Thanks for the clarification, I wasn't sure on that one

 

[kreiten]

I'm new to my 200 and it has been 15 years since I sold by FJ60 (a tragic and long story). I am also new to this forum and it is a gold mine. As I have been playing with my new toy, I have been wondering about how to best use the crawl feature. This thread has answered a lot of questions. Thanks guys. I am still thinking I want air lockers though... Actually, what would happen with a locked rear diff if you tried to to put crawl or turn assist on? I'm thinking nothing good.

I would not engage "offroad turn assist" with a rear locker enganged! Welcome to mud, let us know if ya got any additional questions.

 

[chilibit]

We driver the forest roads covered in snow and ice all the time in the winter, some are as you described, steep with a sheer cliff, if something goes wrong it goes bad really fast. For the majority of the time while on roads like that I am in 4low(mud & sand), with the truck in the lowest gear, center diff locked and chains on the back wheels. I think of "crawl control" more for super short distances(just how I use it). For instance a 30 or 40 foot super steep(up or down hill climb) that is super icy. I have never(so far) had the vehicle lose control while in "crawl mode". Keep in mind "crawl mode" can only run for a limited amount of time then the system will shut itself down. I think for the situation you are describing 4low(mud & sand) and throw the truck in low gear and you should be good to go... just my 2 cents

To experiment a bit, I went down to close the gate and tried Crawl Control (Rock, Speed=5) and before arriving at the bottom (while all was going as expected) suddenly I get an insistent beep-beep-beep but I did not see an icon on the display. Shifting to neutral stopped the beep. Is this the system complaining about heat buildup? Which system? Brakes? If so it does not seem particularly robust. I am on a paved driveway but it is steep. I wonder if I had selected 2 or 3 for a speed if it would have complained sooner.

 

[Romer]

looking at post 1 the instructions imply 1 or 2 for downhill. Good question on why the beeping

 

[kreiten]

To experiment a bit, I went down to close the gate and tried Crawl Control (Rock, Speed=5) and before arriving at the bottom (while all was going as expected) suddenly I get an insistent beep-beep-beep but I did not see an icon on the display. Shifting to neutral stopped the beep. Is this the system complaining about heat buildup? Which system? Brakes? If so it does not seem particularly robust. I am on a paved driveway but it is steep. I wonder if I had selected 2 or 3 for a speed if it would have complained sooner.

how long were you in "crawl" prior to the beep? The system does have a limit due to brakes heating up, I have never hit it in the 200 as the longest I have used it at any one time is 3 or 4 minutes. I did read one account were someone said the system turned off on them after about 20 minutes of use. Where you on snow/ice? Did you use turn assist at all? Was the center diff locked?

 

[chilibit]

how long were you in "crawl" prior to the beep? The system does have a limit due to brakes heating up, I have never hit it in the 200 as the longest I have used it at any one time is 3 or 4 minutes. I did read one account were someone said the system turned off on them after about 20 minutes of use. Where you on snow/ice? Did you use turn assist at all? Was the center diff locked?

No center diff. No turn assist. Dry pavement=Rock. I would estimate I traveled about a 1000 feet up a small grade and then tilted down sharply for 800 feet before I got the beeping. The system did not actually kick out of Crawl Control when it occurred but I suspect that might have been next. Due to steepness, the front (??) brake pulsing is pretty much non-stop. Time might have been 4 minutes or so. I was not monitoring that parameter.

 

[chilibit]

No center diff. No turn assist. Dry pavement=Rock. I would estimate I traveled about a 1000 feet up a small grade and then tilted down sharply for 800 feet before I got the beeping. The system did not actually kick out of Crawl Control when it occurred but I suspect that might have been next. Due to steepness, the front (??) brake pulsing is pretty much non-stop. Time might have been 4 minutes or so. I was not monitoring that parameter.

In normal braking the driver exerts a force on the pedal, that force is multiplied and pressure is exerted on the calipers. That is not a precise scenario but close. In Crawl Control some other device is prompted by a computer monitoring the process and that device has to trigger the brake pressure. This device (taking the driver's place) may be the weak link. It most certainly is not the calipers and pads. Isn't brake pressure on the 200 provided by a separate electric motor rather than vacuum? That would leave out depletion of the vacuum reservoir. I may smoke my brakes dropping out of the Rockies but I don't think I would get this beep, beep, beep business.

 

[kreiten]

No center diff. No turn assist. Dry pavement=Rock. I would estimate I traveled about a 1000 feet up a small grade and then tilted down sharply for 800 feet before I got the beeping. The system did not actually kick out of Crawl Control when it occurred but I suspect that might have been next. Due to steepness, the front (??) brake pulsing is pretty much non-stop. Time might have been 4 minutes or so. I was not monitoring that parameter.

My guess is overheated, which seems a bit crazy being you were not driving very long, really only a handful of things that will give you the beeping sound for crawl shutting down, the main one being brakes are overheating! I believe the system may also warn that crawl will be cancelled if the vehicle exceeds 15mph, haven't seen that happen yet and it would have to be a really steep hill. Apparently if the drivers door is open it will sound the alarm also, haven't tested that theory yet.

 

[kreiten]

To experiment a bit, I went down to close the gate and tried Crawl Control (Rock, Speed=5) and before arriving at the bottom (while all was going as expected) suddenly I get an insistent beep-beep-beep but I did not see an icon on the display. Shifting to neutral stopped the beep. Is this the system complaining about heat buildup? Which system? Brakes? If so it does not seem particularly robust. I am on a paved driveway but it is steep. I wonder if I had selected 2 or 3 for a speed if it would have complained sooner.

One thing to keep in mind also is that "terrain select" and "crawl mode" are two different modes if you will. Meaning if your in 4 low(with the crawl button not activated) the silver dial is your "terrain select" knob, rotating it gives you the different terrain options. The minute you select "crawl mode" by hitting the button that dial is now used to control your speed within "crawl"(1-5kph) and no "terrain select" features are available. If you are going to a really steep incline try a lower speed as the vehicle will control itself better, possibly limiting overheating slightly and also ensuring you do not exceed the speed cap on 'crawl".

 

[chilibit]

One thing to keep in mind also is that "terrain select" and "crawl mode" are two different modes if you will. Meaning if your in 4 low(with the crawl button not activated) the silver dial is your "terrain select" knob, rotating it gives you the different terrain options. The minute you select "crawl mode" by hitting the button that dial is now used to control your speed within "crawl"(1-5kph) and no "terrain select" features are available. If you are going to a really steep incline try a lower speed as the vehicle will control itself better, possibly limiting overheating slightly and also ensuring you do not exceed the speed cap on 'crawl".

I agree. I select 4Lo, then I selected Rock, then Crawl Control which if I understand you means I could select speed which i did at 5kph. I did not realize that Rock (Terrain Control) was voided by the Crawl selection. Never the less, engine rpm never crept above 2000 and Crawl was maintaining 5kph. I would expect it to do that until we we started sliding. But no, none of those were approached. Just the beeping. I think (since rpm's are under control) that setting speed lower would work the brake servo's even harder and result in earlier beeping. Of course I don't really know because I don't seem to have an adequate grasp of the system rules. The tradeoffs between momentum and overheating are not obvious. I have to think about that. My sense was that the braking capability was not at its limit.

 

[kreiten]

I agree. I select 4Lo, then I selected Rock, then Crawl Control which if I understand you means I could select speed which i did at 5kph. I did not realize that Rock (Terrain Control) was voided by the Crawl selection. Never the less, engine rpm never crept above 2000 and Crawl was maintaining 5kph. I would expect it to do that until we we started sliding. But no, none of those were approached. Just the beeping. I think (since rpm's are under control) that setting speed lower would work the brake servo's even harder and result in earlier beeping. Of course I don't really know because I don't seem to have an adequate grasp of the system rules. The tradeoffs between momentum and overheating are not obvious. I have to think about that. My sense was that the braking capability was not at its limit.

based on everything you said above it sounds like you are getting a good idea of the way the system functions at least on the surface, I guess we'll have to chalk this up to the system believing the brakes would overheat if you kept going(no idea why as it sounds as though you were well within normal usage). I agree with you that lower speeds would more than likely work the brakes even harder. The owners manual says that the alarm will sound and then if you don't disengage crawl it will do it for you, and that normal driving is still ok after crawl is disengaged. Based on that I would guess the system is shutting down way before the brakes actually overheat. Just my 2 cents

 

[chilibit]

based on everything you said above it sounds like you are getting a good idea of the way the system functions at least on the surface, I guess we'll have to chalk this up to the system believing the brakes would overheat if you kept going(no idea why as it sounds as though you were well within normal usage). I agree with you that lower speeds would more than likely work the brakes even harder. The owners manual says that the alarm will sound and then if you don't disengage crawl it will do it for you, and that normal driving is still ok after crawl is disengaged. Based on that I would guess the system is shutting down way before the brakes actually overheat. Just my 2 cents

 

[chilibit]

This dog needs to rest I suspect. Thanks for the dialogue. It would be nice to know exactly WHY.

 

[Billfish]

Flux capacitor alarm I expect. Try setting it to yesterday to reset the system.

 

[dr.pow]

Great thread! Thanks to Ken for starting this and all of you for your comments. Apparently I started old school wheeling the same year as Ken did.
I recently got my 2016 LX 570 and despite reading the owner's manual 3 times (I'm on my 4th) I really was struggling with the capabilities of 4Low and was really looking for something like this discussion. Kreiten seems spot on with his comments from what I have read and experienced so far. I have about 1/5 of a mile of gravel/dirt driveway, some quite steep, and I took it out within minutes of getting home to see what these features really do. I was blown away when I tried and figured out what the turn assist would do, given the rear tire dig left in the gravel and how it spun me a good 270 deg. Since my 200 is so new, I will obviously be judicious for awhile (it's a comfortable cruiser hauler to Moab for a few years, and could take that long to come up with armor I think anyway), but I think the best thing we can do is get out and really use these features to see what they can do. I will say that I think that Toyota could do a better job of enlightening us all about these bells and whistles, though not sure how (remember all the FJ Cruise events that they had a few years back? maybe something like that). The owner's manual is obviously limited and the YouTube vids are repetitive and they are no substitute for actual driving.
Looking forward to some snow packed icy driveway action next winter at any rate.

Mark

 

[GOLDY]

And I thought learning our new to us 2008 200's 4wd options was head spinning. Bottom line is, there's definitely no substitute for time behind the wheel. I want it to become 2nd nature to know which mode best suits the situation, especially before attempting a potentially ass puckering obstacle. Having started wheeling in the mid 70's,
74 K5 blazer,then 80 CJ7, in some respects it makes me feel like I'm learning to wheel all over again. Makes me appreciate the "simplicity" of our 3x locked 96 fzj80, aka the crusher. Thanks for all the great info.

 

[dr.pow]

When I was in Moab last week I spent some time messing around at the bottom of Top of the World in the "moderate" section, particularly with the cameras and what they show. A most interesting view (which I think is a new feature) is the one of what's under the truck, taken and computerized from when you were back 10 feet. Only works at crawling speeds- which makes sense.

We checked out the rock art in Sego Canyon. Highly recommend this one, and easy to get to- not that we always want that....