Slow speed brakes, engine brake, crawl control

Wanted to get your guys thoughts on how your using the different tools available. Going down hill I always like to keep the engine in manual and adjust gear to speed that is appropriate for terrain. I am always trying to avoid too much use of brakes over heating them.

Without crawl control manual gear was my main approach here. I have been playing with the crawl control and like the idea of letting the computer and electronics help out. My wife hates the sounds of ABS even with me reassuring her it's fine acting normal. So far it's been mainly me playing with it in rock gardens for short distances which should have limited affect heating the brakes up and shutting down. I like the speed control and being able to just focus on my path adjusting the speed dial as needed. Yes I would love a real crawl gear low range. I did see some videos in deep sand guys stuck and it definitely seemed to work letting the computer get traction. I don't do much sand or try to hit mud. If I go thru mud it's an obstacle I need to pas thru. Spent too many days at carwash cleaning up in past. If I do have to go thru mud I don't think crawl would be my first instinct but maybe this is not correct. Locker and momentum not slowing down to get stuck. Keep acceleration as needed to make it thru the mud without sinking in.

Thoughts on rocks or other obstacles where I really am only trying to control speed? Is using the brakes in 1st gear same difference letting crawl control use ABS?

 

You do have a real low range “crawl gear”. I think if you need engine braking to go slow, 4Lo should be your primary choice to control speed.

The Multi terrain select and crawl control dials…you can use them as needed, but I’ve never really liked what they do for me. Actually, I kind of think they’re dumb.

 

Yes I am in 4 lo when in these scenarios. 4 lo and manual gear selection 1 or 2 using engine braking. Needing slower than that is what I have been playing with crawl but not sure for speed control its any difference than me just using brakes since that's what crawl is doing with the ABS.

 

Personally I don’t really use any of it except for mall terrain select sometimes to change how intrusive the ATRAC will be but really I just go all manual control.

 

I’d rather use the brake pedal in those situations. You can be much smoother on the brakes yourself than letting the crawl control do it.

 

My interpretation of Crawl is that it's intended to simulate a front (and rear) locker on an intermittent, as-needed basis. I'm not sure whether downhill momentum control is also part of that intent, or just a potential "bonus" application.

 

There is probably more to unpack here, but conventional methods work fine and crawl control enhances those methods. Crawl control essentially simulates "real" crawl gear low range with the added benefit of providing just the right amount of power/breaking to make it out of difficult spots and descend down hill in a very controlled manor. Crawl control will be an improvement over manual breaking, but only for certain difficult situations descending or getting out of being stuck in sand/mud.

Ultimately Crawl control and A-Trac are to be used sparingly/short duration and for difficult situations that our human input cant be refined to the level of a computer controlling the breaks/gas. Breaks also can deal with a ton of heat so I really wouldn't worry about over heating to just get out of a bad spot or descend down a moderate hill for a bit. Locker and low gear should be fine for the rest of the time.

A-Trac simulates front (and rear) locker.
Crawl control simulates perfect traction and breaking for getting out of tough spots or descending down hill in a very controlled manor.
And Multi terrain select simply controls the amount of wheel spin since you need less spin for rocks and more for sand and snow.

 

If you need slower controlled deceleration that's exactly what crawl control does, and much better than our feet. You can over or under brake, but crawl control will not. It will always add just enough gas/break to control a specific super slow speed you choose limiting locking up or spinning the tires wildly. But its meant for temporary use in tough spots, not long runs. In the end its going to be up to you, most will feel more comfortable controlling themselves. But boy is it nice descending a steep slippery hill and have no worry of locking up, or getting stuck in the sand and it pulling its self out with ease.

 

1st gear in 4lo in the 4Runner isn’t low ienough that I’d call it a crawl gear.

Yes. The redundancy of the transfer case and locker vs. the ABS-based systems is confusing and makes it difficult to know which to use when.

[Copied from a post in a similar thread:]
Let us harken back to the olden times and look at the predecessors of Crawl Control. Before ABS, descending a steep incline with challenging traction issues was problematic. If the vehicle had a low enough crawl speed the descent was somewhat easily controlled. But any application of the brakes came with the risk of locking up the wheels on the slippery surface. With the vehicle now sliding, steering inputs were meaningless and the driver’s only chance of regaining control was to gently pump the brakes, which resulted in an increase in speed and momentum, resulting in even more risks.

The first vehicle I owned with ABS traction control was a late ‘90’s Discovery with “Hill Descent Control” and I was pleased at how well it worked on a nearby trail on a descent typically carpeted with pine needles. The idea was that the vehicle would slowly descend in such a way that that the wheels would never lock up, and even if they began to slide there was always some measure of steering control.

Having grown up with old school 4WD vehicles, like many of you, I am frequently quick to eschew all the nanny stuff. But I must admit that descent-control devices can perform some tasks with an ease unachievable even by highly skilled drivers.

 

Agree with the crawl gear not being crawly enough, part of the reason I put it in quotations The reason I mentioned it is because the OP wasn't clear if he was using low at all, or just shifting into 1st in 4hi.

Regarding the downhill assist, that’s where I see the most potential use, but where I struggle the most with trust issues lol. I’m still a newb off-road, and maybe a bit overcautious when it comes to steep descents or climbs. If I’m scared that losing traction will end up with me on my roof, I’d be looking for a way around. If push comes to shove and I have no choice, as can happen on trails, then I think would be more afraid of relying on downhill assist vs doing it myself. What if it ends up being too fast for comfort? What if I touch the brakes mid hill? …will that shut the downhill assist off? A lot of questions that I need to process when it’s time to descend. It’s a tool I guess though. I’m sure there’s a time and place, but I have yet to get enough practice with it to feel comfortable in it’s use, when it would really matter.

I rarely find myself in these severe situations though (actually never, so far). Most descents i’ve done aren’t crazy enough to make me doubt my ability brake for myself.

The only time I’ve used the overhead dials for effect is when I was alone, facing a mud bog of questionable integrity. I didnt have enough experience with how much wheel spin I needed for mud. I didn’t want to go full-send because that’s how you break stuff. So i used the mud selection, and I got through.

 

I totally get it. Taking your foot off the brake on a steep descent goes against all reason.

ETA: regarding experience: about 20 years ago I took an off-road driving course. It was tailored to military, law enforcement and other outdoor government agencies. 5 days and 4 nights on the Rubicon trail. It was very educational and a real confidence builder. I recommend something like that.

 

Help me out on guidance for mud and crossing strategy. I agree too much speed equals breaking stuff. On mud does it really come down to how deep it is before a hard bottom? Mud can also come in so many variations depending on soil type......

I get nervous and rely on skinny pedal and locker but would love to crawl thru it if makes sense.

 

My experience with mud is scant, but from what I’ve seen you’ve got your type 1 mud that’s just soupy dirt, and then your type 2 mud that is slicker than snot and sticks to everything. Type 1 is easy to navigate with perseverance. Type 2 requires special knowledge and special tires.

 

I have never needed dedicated mud tires and have to accept limitations of AT tires. Pretty easy to turn a tire into a racing slick packed with mud.

 

I like the type distinctions

I wouldn’t call this advice, but rather what I’ve done…. If I expect the mud to be passable, I poke the area looking for bottom, and looking for boulders…especially in areas with standing water.

Then I look to make sure there is a tree on the other side that I could use as an anchor for winching should traction boards not work.

When I decide to go, I’ll decide on 4hi or 4lo and the gear I want. I aim to enter at a speed that gives me enough momentum to get through maybe half the hole. Once in, I increase throttle with the aim of maintaining the same speed, allowing the wheels to spin in order to do so.

I would avoid crawling through it…unless it’s ’s just a wet trail, with a good bottom.

If it’s clay, I’d probably back up as far as I need to turn around. That’s just asking for trouble lol.

 

Well, you will have to get out and survey the obstacle (mud) for depth and how difficult it looks like clay mud vs regular dirt mud. lol
You also need to be prepared with traction boards and maybe a winch. A good mud tire is important too, even if its an AT leaning toward a mud tire like my Duratracs.

Momentum is important for mud and fine if you survey the obstacle properly. Crawling in mud may be tricky if its deep and clay like, I try to avoid mud obstacles.

 

I avoid mud unless no other path forward. Maybe it's just being old and already spent to many hours at the carwash trying to get the mud off of and out of everything.

 

I’m in my late 40s and making up for lost time playing in mud. I try to avoid it, but we have decent national forests with good trail networks which allows me to cover lot’s of ground on my outings. Mud will happen, and is fun in moderation. But the cleaning! I’m particular, so I pretty much assume I’ll be spending two or three afternoon sessions with the garden hose. I spray everything off! Talk to me in a few years though to see how I feel about mud lol