When to use 4 low? (1 Viewer)

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No right or wrong way to do it. I have an ARB dual + morrflate setup so airing back up is super quick to the point that it’s almost Never a bother to air down. My rig is heavy and airing down just makes the ride so much more comfortable.
I’m looking at the MORRflat, what size is it when stowed? Occasionally, I’ll have 6 tires to inflate and there’s gotta be a better way than the single hose I’m using now.
 
I’m looking at the MORRflat, what size is it when stowed? Occasionally, I’ll have 6 tires to inflate and there’s gotta be a better way than the single hose I’m using now.
I have a morflate like setup - I store it in a round jumper cable bag, if that gives you a general idea.
 
I’m looking at the MORRflat, what size is it when stowed? Occasionally, I’ll have 6 tires to inflate and there’s gotta be a better way than the single hose I’m using now.
I don’t have the MORRflate, but I do have the Indeflate four hose, similar product. In the photos in my attached post you can see it on the right end of the shelf in the back end. Doesn’t take up much space, the MORRflate when bagged looks to be about the same.
Post in thread 'What have you done to your 200 Series this week?'
What have you done to your 200 Series this week? - https://forum.ih8mud.com/threads/what-have-you-done-to-your-200-series-this-week.818471/post-13831849
 
Interesting reading through these comments.

I'm not a huge off roader guy but had a 6cyl Jeep YJ (project/toy) in my past. Whenever I used 4L it was for rock crawling (under 10mph). Is it a normal thing to use 4L and cycle through 3-4 gears? Maybe I'm used to old school (plebian) vehicles but I would never think to shift my LX into 4 low to get up to third gear or so. I'd just leave it in 1st.

Not hating, just thinking out loud. Interested to see other perspectives.
 
All,
Thank you for your input! I put it to use today on Last Dollar road (I don’t think you even really need 4x4 for this road, but it’s a good starter road for nubes like me). I immediately put it into 4-low when I hit the dirt.

Nobody came up with a reason not to put it into 4-low, so I figure I might as well do it.

Though when I get an OBD reader I’ll do some testing on how 4-low affects transmission temps.

It certainly helps slow the vehicle down when descending.
And it also helps keep me below 20mph on roads where it would be stupid to go faster (but I get stupid occasionally).

But a couple of follow up questions:

@tbisaacs: would you air down for a very simple dirt road like that? I didn’t because I know it’s only a two hour drive or so and was lazy.

All: how about the center dif locker? I didn’t lock mine. When would you do that?

All: when going up an incline, do you keep it in manual and pick the gear or do you leave it in 4-low auto?

Tomorrow: Ophir pass.
(Happily Black bear and Imogene are still closed. So I don’t have to come up with excuses on why I didn’t do those.)

It's good to use the tools and get to know them well before really needing them. Trying to learn how to engage and control the vehicle when in duress is needless to say, not the best idea. It's not like a cheat code to take pride in not using.

Much like airing down. The tires become an integral part of the suspension soaking up bumps that otherwise would transmit through the suspension and chassis, increasing wear and tear.

Center diff lock is handy in more than just loose climbing situations. It's super easy to activate, just hitting a button at speed, up to ~60mph. It turns off traction control allowing more liberal use of throttle. In loose surfaces like sand and snow, can potentially mean the difference in getting stuck, because traction control killed power and momentum. Just like airing down, it's better to anticipate the use of it, before getting stuck. At least here in the southwest where fine silt and sand can exist even in what seems like a featureless fire road, is why I air down more often than not. Center diff lock is also fun as it enables more lurid throttle application without traction control killing the fun.
 
CDL on a system like the stock 200 with open diffs also take you from 1 wheel drive to two wheels driving. Add in lockers front and/or rear and you can increase that to three and four wheels driving.
 
One thing that hasn’t been emphasized enough yet in this thread is the advantage of using 4lo and the center diff lock in sand. The software programming for 4lo mud/sand setting allows wheel spin and works much better in my experience than simply turning off traction control. Momentum can be kept up with enough skinny pedal use and the whole vehicle just behaves better. I’ve towed heavy utility trailers through long sections of deep sand on forest roads using 4lo and locked center diff without even having to air down. In 4hi on those roads I’ve been bogged down (but not stuck) more than I’m comfortable with.
 
It seems that a lot of folks on this thread love data, like transmission fluid temp. That’s all good but do you know how to interpret the data? Ever had an issue due to high transmission fluid temp? What is ‘high’? I have no idea myself but doing this for 40 years tells me just cause you have data doesn’t mean you have clue what it means. Ive towed big trailers through nasty stuff. I’ve offroaded steep technical trails on triple digit days. Never had an issue.

Just my 2 cents worth. I tend not to obsess over data i either don’t have solid ranges for or, more importantly, have no way to influence.
 
It seems that a lot of folks on this thread love data, like transmission fluid temp. That’s all good but do you know how to interpret the data? Ever had an issue due to high transmission fluid temp? What is ‘high’? I have no idea myself but doing this for 40 years tells me just cause you have data doesn’t mean you have clue what it means. Ive towed big trailers through nasty stuff. I’ve offroaded steep technical trails on triple digit days. Never had an issue.

Just my 2 cents worth. I tend not to obsess over data i either don’t have solid ranges for or, more importantly, have no way to influence.
Ha! That was going to be my next question: what is “too high” when it comes to the transmission temp?

It will be interesting and informative to see how the temps vary between 4-low and 4-high (once I have the reader) but until I know what “too high” is, it won’t help me much.
But I bet somebody here knows that piece of info or I can ask Dr. Google.
 
It seems that a lot of folks on this thread love data, like transmission fluid temp. That’s all good but do you know how to interpret the data? Ever had an issue due to high transmission fluid temp? What is ‘high’? I have no idea myself but doing this for 40 years tells me just cause you have data doesn’t mean you have clue what it means. Ive towed big trailers through nasty stuff. I’ve offroaded steep technical trails on triple digit days. Never had an issue.

Just my 2 cents worth. I tend not to obsess over data i either don’t have solid ranges for or, more importantly, have no way to influence.
TC temps in the 240° range while in 4H, 190°’s in 4L. This is forest service roads after a few miles up hill at 15-30 mph, both with and without my 4K lbs camper.

I’m not transmission expert but 240° is outside of my comfort zone, especially when I can switch to 4L and drop those substantially. Plus, once I’m over the up hill I’ll be descending and brake temps will rise.

Again, there are lots of irons in the fire in all the scenarios being presented. I’m on 33 inch tires with bumpers and armor, weight is a factor, add the camper and 4L makes sense for me.
 
Google tells me this (though I need to search more since this is just one data point):

It is estimated that close to 90 percent of automatic transmission failures are caused by overheating, and the main reason they overheat is because of overworked transmission fluid.

The optimal temperature range for transmission fluid is 175 to 220 degrees. Above that, for every 20 degrees bad things happen, starting with formation of varnish at 240 degrees, followed by seals hardening, plates slipping, seals and clutches burn out, carbon is formed, and, ultimately, failure.
 
It seems that a lot of folks on this thread love data, like transmission fluid temp. That’s all good but do you know how to interpret the data? Ever had an issue due to high transmission fluid temp? What is ‘high’? I have no idea myself but doing this for 40 years tells me just cause you have data doesn’t mean you have clue what it means. Ive towed big trailers through nasty stuff. I’ve offroaded steep technical trails on triple digit days. Never had an issue.

Just my 2 cents worth. I tend not to obsess over data i either don’t have solid ranges for or, more importantly, have no way to influence.

This is a good point. Practically, the 200-series will do it all, all day, in just the standard drive mode. It's probably what most do and their points echo that.

I think the other part of this thread is what is best practice. From the varied responses, there's a spectrum, and without a right or wrong. Or until obstacles get so extreme, that leaning on certain 4x4 tools becomes a necessity. I'll say the tools on Toyota's platform aren't the most intuitive, and would be worth exercising before the need arises.
 
I use 4lo pretty infrequently; namely, only when I want more torque or speed control. This usually means: when I'm climbing or descending steep grades, especially long ones. When climbing long, steep grades it helps with transmission temperature control, and when descending it helps with more engine braking and keeping speed in check.
 
If you feel the truck is doing the job well enough in high range, then leave it in high range. It is indeed easier on the transmission and torque converter to use low range, and it helps keep transmission temps down, but for most general mildly bumpy forest service roads, I prefer the smoother 1-2 shift in high range rather than the abrupt jerky shifting (1-2-3) in low range. This is for flat or uphill. Low range for the downhills because only boneheads ride the brake the whole way down the trail. :hillbilly:

On a tougher trail, low range the whole time and I'll shift manually to pick the gear I want. In that sort of scenario, I'll pretty much never go above 3rd gear, that's just what's appropriate for the trails around here and my driving style.

You'll figure out what works for you 👍
 
Ive really only used 4LO to “exercise“ it. It’s very rare that I come out of 4H on the beach. I air down to 18psi and turn off all the helping gizmos, lock the C DIFF and just have at it. It’s rare that I’ll switch to 4LO in the snow either. But you guys do like to call us “flat landers“ so my demographic is very different.
 
Airing down makes the absolute biggest difference.

If you’re generally going 30mph or less, regardless of road ‘difficulty’ (smoothing forest service (fs) road to catastrophe) I air down. While you’ll see all sorts of vehicles on a normal fs road, they’ll be dodging potholes and typically going very slow. It really doesn’t matter what type of vehicle (I saw a very capable lifted Colorado, doing this, for example) if you aren’t aired down most people don’t have the bones/skill/lack of mechanical sympathy to drive fast and endure the beating they are getting from road pressure tires, the difficulty staying on line getting bounced around/ and the constant skidding of the hard tire on loose surfaces. I guess I’m thinking of moderate to highly potholed roads, but how would you know ahead of time unless you have been on the road recently?
I’m probably a faster type driver, but airing down is like a dirt road superpower.
It is far more comfortable, it is far more forgiving of line choice, and it is much faster.
Even counting the air down time it is faster.
There have been several situations where I was on the shoulder airing down (this was before the apex deflators) and got passed by 100s, jeeps, Camry etc. they always get caught within a couple miles. Like they’re standing still usually. This happened even on a short 3 mile lake road. And they had the bone jarring ride in and out too.
I’ve also caught and passed vehicles a short distance from the paved roads- one or two miles. And even with getting out the inflation system and airing up on 35s, been ready to go as they trundle by creaking and pitching.

The only downside to airing down is having to have a solid compressor solution to air back up.

The more user friction you can eliminate the more likely you are to air down, and the more benefit you’ll see.
It’s why a lot of folks have mentioned two flate and four flate systems (which can be used for inflation and deflation, and which automatically balance tire pressures).
Hard mount compressors, like the arb twin, and dedicated deflation valves, like the apex deflators, ease use even further.
 
Airing down makes the absolute biggest difference.

If you’re generally going 30mph or less, regardless of road ‘difficulty’ (smoothing forest service (fs) road to catastrophe) I air down. While you’ll see all sorts of vehicles on a normal fs road, they’ll be dodging potholes and typically going very slow. It really doesn’t matter what type of vehicle (I saw a very capable lifted Colorado, doing this, for example) if you aren’t aired down most people don’t have the bones/skill/lack of mechanical sympathy to drive fast and endure the beating they are getting from road pressure tires, the difficulty staying on line getting bounced around/ and the constant skidding of the hard tire on loose surfaces. I guess I’m thinking of moderate to highly potholed roads, but how would you know ahead of time unless you have been on the road recently?
I’m probably a faster type driver, but airing down is like a dirt road superpower.
It is far more comfortable, it is far more forgiving of line choice, and it is much faster.
Even counting the air down time it is faster.
There have been several situations where I was on the shoulder airing down (this was before the apex deflators) and got passed by 100s, jeeps, Camry etc. they always get caught within a couple miles. Like they’re standing still usually. This happened even on a short 3 mile lake road. And they had the bone jarring ride in and out too.
I’ve also caught and passed vehicles a short distance from the paved roads- one or two miles. And even with getting out the inflation system and airing up on 35s, been ready to go as they trundle by creaking and pitching.

The only downside to airing down is having to have a solid compressor solution to air back up.

The more user friction you can eliminate the more likely you are to air down, and the more benefit you’ll see.
It’s why a lot of folks have mentioned two flate and four flate systems (which can be used for inflation and deflation, and which automatically balance tire pressures).
Hard mount compressors, like the arb twin, and dedicated deflation valves, like the apex deflators, ease use even further.

I'm glad you wrote this. Exactly my thoughts.

Definitely added safety factor. Including protection against punctures.
 
I'll pile on. Air down! Even if it's just 25%. It's more comfortable, offers better traction (climbing and stopping), and gives you better puncture resistance. AND, what many forget to mention, it's better for the road. Washboards don't occur in nature, they're the result of people driving too fast on dirt roads with hard tires (freeway inflation pressures).

I don't have anything fancy, just a Jaco Tire Deflator to make airing down faster, and an inexpensive VIAIR 88P portable Air compressor. Do I wish I has something bigger and faster? Yes, and I will someday. But it does the job and gets me from 26 to 35 psi in 2min per tire (285/63R18 Nitto RGs). Worth it!
 
Here is a really cheap and fast way to air down.
buy 4 of these:
1655865948242.png


You can attach Staun valves (or similar) to these as well if you don't want to air down too much.
These will also attach to the screw on hoses that come with viair\smittybilt compressors to make airing up faster.
 
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All,
To follow up on this thread:

I did get the ODB reader scanner along with ODB Fusion and today I re-did Last dollar road. This is listed as “easy” in most off-roading books I have seen but there are still some steep parts.
My plan was to run it twice - once in 4-high and once in 4-low while watching the transmission temps.

Problem was, I did 4-high first and the temp got all the way up to 214. If the fluid starts to break down at 220, I felt this was pushing the limit so I switched to 4-low. The transmission temp very quickly dropped to 180 and hovered around there for the rest of the climb.

Not to say I didn’t trust all you guys who are much more knowledgeable than me, but this evidence further convinced the use 4-low in most off-roading situations. Certainly when climbing.
 

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