proper use of 4Lo

hey guys just wanted to say thanks for some of the info, i have been light on the use of my L4 because the trails i go on are not bad by any means (stock taco, new driver) and I think ill use it a little more often, just to save my converter...

after this thread and the towing regularly thread, makes me wish I had the tranny cooler. I might look into an aftermarket one later...

 

With my manual transmission, it was pretty much impossible to start out in anything other than 4lo on the beach. If i was facing downhill then I was able to use 4hi.

 

Gentle is the correct word
Its all about balancing things. Soft sand puts strain on tranny but Too much RPMS and there is a lot of heat too quickly generated in the engine. OBX is good example 4x4 area is 20+ miles long and requires beach driving. Plenty of people end up with 4HI and over heated transmission, also there is plenty 4L and overheated engines. (coolant boiled)
Area by the dunes usually is super soft sand that can swallow truck like a quick sand. Area by the water has almost concrete like sand.
So one way you can run 4HI other way you better off in 4L and slow it down.
Problem with soft sand is that tranny needs to work against the sand and if your truck is not fully locked (Front/Rear lockers) there is always some drag on the system that results in heat a lot of heat that is not transfered out in time.
This is where no electronic traction system will ever be better then fully locked truck. Ability for 4 wheels to rotate and equally pull can not be mimicked.
Also good tranny cooler is a must.

 

I drove the Outer Banks back in March. At first I didnt air down any at all. Neither 4lo or 4 hi was very good. Once I stopped I found it almost impossible to get moving again in either range but 4lo just started digging immediately with very gentle throttle applied. I aired down to 20 psi and moved along effortlessly in 4hi. Im going back next week. Ill report back if I find any different, but for now my experience on that beach is that air down and 4 hi will get you going along no problem. I have a manual transmission.

 

To do it, is proof... If you can't move from a stop in sand, then you have too much air in your tires. Starting in L4 will give you power to move... but you will move down more than forward if you are not floating with your tires. Once I did move forward from a stuck in sand, at full pressure... and that was with A-TRAC. Without A-TRAC, let the air out!

 

Just to clarify... you are saying use 4Hi for super soft dune sand and 4Lo for concrete like sand?

 

No, no... 4 Lo is for slow crawling traction needs... (Nay, are you reading anything I type?) If the beach is like concrete, you could be in 2WD... I am not lying to you amigo...

I have driven in sand dunes...
Can you see the little photo next to my name, on the left? That is on Devil's Slide sand dune, Ocotillo Wells, CA... In 4-High... and with TRAC, tires at 32 psi.

If the sand is super soft, then low range will only dig you in deeper... You must deflate if you dig in... in order to float.

Torque and horsepower (L4) does not improve anyting in deep sand.

Have you seen this thread?: http://www.tacomaworld.com/forum/travel/82878-baja-beach-fun-tacoma.html

 

No I've been reading your posts and it makes sense. I'm just trying to understand what BlueT was saying.

You did say you moved forward with ATRAC on in the sand which confused me a little, isn't ATRAC only available in 4Lo?

 

4Hi for snow and high speed situations with limited traction.
4Lo for situations where you have to slow down due to steep hills or extremely rough terrain.
Usually your engine will be bogging already if you should be in 4Lo and aren't.

 

Yes... I have to presume you have read my previous posts which usually always explain everything... I am just 'that way'! LOL

1) In the winter, with a light load, I was able to drive the dry upper beach sand without letting any air out... It was the first time on a Baja beach with my 2010 and having TRAC (limited slip front and rear) in 4-HIGH. I was thrilled, as my '05 and '01 wouldn't have done so well, without dropping the air. I began to sing the praises of TRAC on the new Tacoma Off Road TRDs.

For fun, I turned the TRAC off (VSC OFF MODE) and tried driving with open differentials in 4-HIGH... so it was like my '05...

I soon began to bog down in the sand with one tire in the front and one in the rear spinning... just like my '05 would have at full tire pressure.

I was stuck... so, without getting out and clearing away the built up sand or without letting any air out of the tires, I turned on the A-TRAC (yes, it only works in 4-LOW)... The truck made the horrible A-TRAC noises, shook a bit and drove out of the stuck!!! I put the transfer case back in 4-HIGH, with TRAC back on... and continued to drive about as before!

This proved the tractor-like ability of A-TRAC to get you moving when all else failed (short of letting air out, etc.)... and proved TRAC in 4-HIGH was superior to the pre-'09 non-TRAC Tacomas, in sand (and other conditions).

2) This past summer, with high heat and a heavy load in the truck, I was not able to drive with ease at 32 psi in the tires... conditions were changed... and deflating to 15 psi was all that was needed... I briefly tried L4 with A-TRAC (before deflating) but it still struggled and was digging in, and I was drifting closer to the water's edge on the steep beach. 15 psi and 4-HIGH was the dream ticket... I posted photos of before and after deflating so you could see the difference... in the link I posted above.

So, if another said he used L4 in the sand, that's fine... but you rev the motor far higher than necessary, and risk spinning the tires with the increased torque.. and spinning tires in sand gets you nowhere, and will bury you deeper. I like driving over 25 mph on the beach, and in L4 your motor would be sceaming... and your gas needle dropping. Save L4 for when it is needed, climbing, descending, getting out of a stuck, etc.

 

So only use 4Lo+ATRAC when you are struck in sand... is that what you are saying?

This is the part I can't understand. You say 4Lo will just dig you in deeper but then you give me an example of how you used it to get out of being stuck.

 

Well, going into 4-LOW is the only way to have A-TRAC... A-TRAC works at getting you out of a stuck.

Who wants to get stuck in the first place, and who wants to drive slow on a big sand beach? 4-HIGH and deflated tires will PREVENT you from getting stuck, and you can cruise at 40 mph if you want. Perhaps if conditions are like I had in the winter, you won't need to deflate with TRAC in H4?

In the other posters comments about using Low Range in the sand, he never mentioned A-TRAC (if he even has it).

So, H4 for the beach... try it a 32 psi. If you struggle and begin to bog down... STOP and deflate the tires, then continue.

If you start in L4 instead, your RPMs will be up and your tires will want to spin... You might power through the sand (if it isn't deep)... But why struggle and rev up the truck...? Getting through sand isn't about power, it is about traction and floatation... more with floatation (I have seen 2WD cars and trucks on beaches in Baja with lowered tire pressure doing the job).

As soon as the A-TRAC got me unstuck (back on top of the sand), it was counter-productive to stay in L4, as I wanted to drive with ease... Even with A-TRAC, being in L4 just made sand driving harder... It is a breeze, with no over-working of the Toyota in H4. Lowered air pressure or not, depending on the kind of sand and the conditions (weather, moisture, etc.).

 

See this is what I'm having trouble with. Regardless of ATRAC, you are still in 4Lo. How can something can both get you stuck by digging in and also get you out when you are stuck?

The way I see it, if something will get you stuck in the first place, it's probably not the best tool to get yourself back out. What am I missing?

From my understanding of physics, 4Hi will work best on slippery surfaces since you are less likely to overpower something with very little coefficient of friction. This is why in some vehicles with "select terrain" systems, they actually start out the vehicle in 2nd gear for snow mode.

However, in some cases such as climbing and going over lumps, you will need more torque. Yes you are still likely to cause a wheel spin, but it's a compromise you make in order to have enough power. You avoid the slippage by being gentle on the acceleration.

Does 4Lo work when you are already digged in because you have harder fresh terrain to work with? I must be missing something.

 

My opinion is use 4 Low for almost all Off Road situations, mostly because if you have an OR model, it allows use of ATRAC, and the rear locker. I also find regardless or the situation, it's available torque, allows quick and appropriate application of torque. Such as in a mud hole, the truck will spin the tires, instead of bogging down. On sand, I found that it provides closer gear spacing, in the low speed ranges usually encountered while climbing. So it keeps the truck rpms up, and doesn't get caught between gears. Basically, the only time I have found 4 low to be a disadvantage, was on snow.

 

Coming from lots of high hp cars i think the basic breakdown is...

4lo = High torque, uneven terrain, slow speed movement, throttle sensitive

4hi= High speed, slick yet relatively smooth terrain, suv full time awd type traction

 

Classic debate, crawl in unprepared, without out the guns blazing, and try to extract yourself using the available tools (ATRAC, Locker, TRAC, etc). Or go in prepared, and don't get stuck. I think the first methodology comes from city slickers looking for adventure, the second from people who need to get somewhere, and aren't out purely to screw around.
But remember, per the Fanboys, these trucks aren't really for off-roading, trail use only.

 

It is A-TRAC, not Low Range that got me unstuck... A-TRAC only works in Low Range... so no other reason to connect the two systems... Get unstuck with A-TRAC, then put it back in High Range... if you are sand driving (beach)!

If you take my advice (above in an earlier reply) you would NOT be stuck, in the first place... and would not need to use A-TRAC (in L4)!

Now, can you seperate the two... 'L4' for climbing (with A-TRAC), and 'A-TRAC' for getting unstuck?

By-the-way, with A-TRAC you just have no need for the Rear Locker... A-TRAC gives you front and rear locker traction without affecting the steering. Rear Locker has a 5 mph speed limit and is for getting unstuck, only (per Toyota). A-TRAC has neither limit.

 

Stock 2020 Tacoma OFFROAD at the dunes, didn't have to let the air out on my tires. Did pretty well with the 4HI

for Sand, should I use 4HI? or 4LO?

and how about SNOW?

 

In sand, H4... Traction control on max (whatever they call it now).
If you get stuck, then L4 with Crawl on.

 

This ain't rocket science. All 4 lo does is reduce the trucks gearing. If 1st gear hi range isn't geared low enough for the job you need to do then going to lo range reduces the gearing.

1st gear on most newer Tacoma's is 4.31:1. With a 3.73 rear axle gives you about 16:1 gear ratio in hi range. Going to lo range reduces that gearing further. I'm not certain what the exact reduction is, it varies by year and manufacturer, but it would be about 3:1 on most vehicles. Jeep Rubicons are 4:1. So in lo range you're looking at about 48:1 gearing on a Tacoma.

If you need more power to get where you're going such as up steep hills or when pulling someone else out of a jam then go go lo range. Or if driving over rugged terrain where you need to go very slowly without stalling the engine. This allows you to maintain momentum with very low engine rpm. In hi range you'd need more rpm's to get the same speed and you have less control. It also uses engine braking for going down steep hills without having to use your brakes. You have much more control over the vehicle.

Getting moving in sand is hard and lo range helps. You can do it in hi range, but are more likely to overheat the engine. Using 4 lo does nothing to help get you unstuck.

Mud and snow are usually best in hi range. It is actually easier to get moving in snow/ice in higher gears. If possible hi range and start in 2nd gear. This way the transmission is slipping not the tires. It is a lot harder to prevent wheel spin in lo range in snow/ice In mud you need wheel speed to sling mud out of the tire tread. Even the gnarliest mud tires will fill up with mud and look like a peeled onion if you don't turn them fast enough to sling the mud out. There is no finesse getting through mud. Just muscle.