Trail premium vs the Limited with respect...

[Bruin1md]

Much appreciated

Because when putting the trail edition or SR5 in 4hi, it's locking the transfer case, not the rear differential.

Where as the limited has a torsen type differential INSIDE the transfer case that allows it to slip, when not locked.

We are talking about two different components, a transfer case and a rear differential inside the rear axle. The trail edition has a rear differential locker, which no other trim has stock

Now I've got it--thanks. But in both scenarios (locking the transfer case in 4Hi or rear diff within the rear axle as in 4Lo), it is dangerous to be doing much turning of any kind correct? So when using 4Hi in the snow or lots of loose gravel or icy roads, turning should be kept to a minimum if at all possible?
The concern is damage to the axle and componenents of the locking mechanism, is that correct?

I've got a 'basic' understanding of the part time/full time 4wd systems, but obiviously still need further education on the components in greater depth.

 

[M1911]

Got it-- but then why the 'pulling' feeling when it's on 4High if the car is being reversed and turned at the same time? If no locking is being engaged in this mode, why is it dangerous to do this as opposed to just using the truck while driving straight in the requisite conditions with minimal turning involved?

That's the part that I'm still not clear on (w/r to the 4H feature).

Because it is a part-time 4WD system. Once you put it in 4WD, the front and rear driveshafts turn at the same speed. When you go around a corner, the rear of the truck travels a shorter distance than the front of a truck. As a result, the rear driveshaft wants to turn fewer revolutions than the front driveshaft, but it can't, because of the transfer case. When you are offroad, you have enough tire slippage that you won't break anything, though it does make it harder to turn.

In contrast, the Limited's fulltime system has a center differential. That center differential allows the front and rear driveshafts to turn at different speeds.

 

[M1911]

Now I've got it--thanks. But in both scenarios (locking the transfer case in 4Hi or rear diff within the rear axle as in 4Lo), it is dangerous to be doing much turning of any kind correct? So when using 4Hi in the snow or lots of loose gravel or icy roads, turning should be kept to a minimum if at all possible?
The concern is damage to the axle and componenents of the locking mechanism, is that correct?

I've got a 'basic' understanding of the part time/full time 4wd systems, but obiviously still need further education on the components in greater depth.

4 HI in a part-time system is just fine to use on snow or loose gravel. Turn as much as you want. You'll have enough tire slippage that it won't damage anything.

The only issue is on pavement that isn't snow covered.

There really isn't any need to lock the rear diff just driving around on snow. I wouldn't lock it except in the most difficult offroad conditions or if I was stuck.

 

[Dexter Morgan]

This is the annoying thing about part time 4WD. Even if its just raining, or slightly damp, I'd like to be able to just put it in 4WD and leave it there without worrying about turning sharply and so forth.

And yet I cannot purchase a limited because you can only get them with a sunroof and the headroom is dismal.

 

[Biggcrisp]

This is the annoying thing about part time 4WD. Even if its just raining, or slightly damp, I'd like to be able to just put it in 4WD and leave it there without worrying about turning sharply and so forth.

And yet I cannot purchase a limited because you can only get them with a sunroof and the headroom is dismal.

You do not need 4 wheel-drive to drive in the rain, snow or ice. VSC will cradle you in it's womb of nanny controls.

4 wheel drive is handy to get you moving in snow, ice or mud (only) if you are having difficulties with VSC during take-off from a stop. It should NEVER EVER be needed in the rain. GAWD.

It has NOTHING to do with stability or stopping power.

 

[Bilbo]

I spent many happy years with my part-time SR5. And certainly didn't spend all that time thinking "Gosh, if I only had a full-time 4WD." That said, I'm reminded of a statement once made by Sen. Phil Gramm of Texas about gun ownership:

"I own more shotguns than I need, but not as many as I want."

I don't recall a single person on this forum who has ever said they wished they could swap their full-time 4WD for a part-time.

 

[Bruin1md]

You do not need 4 wheel-drive to drive in the rain, snow or ice. VSC will cradle you in it's womb of nanny controls.

4 wheel drive is handy to get you moving in snow, ice or mud (only) if you are having difficulties with VSC during take-off from a stop. It should NEVER EVER be needed in the rain. GAWD.

It has NOTHING to do with stability or stopping power.

This has been very educational for me, but it begs the question: why then create a full time 4WD system at all like the one with the Torsen limited slip center diff on the Limited?

If there is no advantage to 4WD in rain/heavy rain and/or cold/slick road conditions --ie if 2WD with good tires and traction control is sufficient-- then what added benefit does full time 4wd provide?
When I read 1engineer's write up, there does seem to be an advantage to having the full time set up for non ideal pavement driving as I described above, but after reading many posts here --including yours-- that benefit seems to be called into question.
Thanks.

 

[1engineer]

This is the annoying thing about part time 4WD. Even if its just raining, or slightly damp, I'd like to be able to just put it in 4WD and leave it there without worrying about turning sharply and so forth.

And yet I cannot purchase a limited because you can only get them with a sunroof and the headroom is dismal.

How much do you slip in the rain? Typical values of coefficient of adhesion (mu) of a rubber tire on asphalt (concrete is slightly higher) is around 0.8 for dry conditions and around 0.6 for wet asphalt. Compare that to 0.2 for hard pack snow and 0.1 for ice. Bottom line in traction situations wet pavement is not bad.
If you have an AWD vehicle like a Subaru or even a partial AWD vehicle like a CR-V the AWD does not even engage (CR-V) and the Subaru won't detect any slip in normal driving conditions.

The key is VSC and TRAC along with ABS. These electronic aids will keep you pointed in the right direction regardless of how many tires are pulling or pushing and Toyota's VSC system is very good.


Now, I'm 6'4" and I fit just fine...with a sunroof in the 5th gen 4Runner. I suggest you test it out and adjust the seat a bit. I have about an inch between my head and the sunroof surround.

 

[M1911]

You do not need 4 wheel-drive to drive in the rain, snow or ice. VSC will cradle you in it's womb of nanny controls.

4 wheel drive is handy to get you moving in snow, ice or mud (only) if you are having difficulties with VSC during take-off from a stop. It should NEVER EVER be needed in the rain. GAWD.

It has NOTHING to do with stability or stopping power.

4WD helps you go, but it doesn't help you turn or stop. That is why I run Nokian snow tires on my 4Runner in the winter.

 

[M1911]

This has been very educational for me, but it begs the question: why then create a full time 4WD system at all like the one with the Torsen limited slip center diff on the Limited?

If there is no advantage to 4WD in rain/heavy rain and/or cold/slick road conditions --ie if 2WD with good tires and traction control is sufficient-- then what added benefit does full time 4wd provide?
When I read 1engineer's write up, there does seem to be an advantage to having the full time set up for non ideal pavement driving as I described above, but after reading many posts here --including yours-- that benefit seems to be called into question.

Fulltime 4WD allows you to always be in 4WD. This is helpful when the road goes from snow covered to wet to dry and back.

It also makes it easier to turn while in 4WD, even on slippery surfaces.

The Limited's fulltime 4WD system does everything the part time 4WD system does, and more. The main downside is cost.

 

[1engineer]

This has been very educational for me, but it begs the question: why then create a full time 4WD system at all like the one with the Torsen limited slip center diff on the Limited?

If there is no advantage to 4WD in rain/heavy rain and/or cold/slick road conditions --ie if 2WD with good tires and traction control is sufficient-- then what added benefit does full time 4wd provide?
When I read 1engineer's write up, there does seem to be an advantage to having the full time set up for non ideal pavement driving as I described above, but after reading many posts here --including yours-- that benefit seems to be called into question.
Thanks.

1. You ( or the typical soccer mom) never have to worry if the roads get slick (with snow not rain) and
2. In specific situations, the full time 4WD (again, in mud or snow or dirt) will maintain tractive effort a bit longer before VSC and TRAC would kick in.

Let's say you take your full time 4WD around a snow covered corner at 35 mph. Now I am following close behind in my part time SR5 4WD. Yours is in standard mode which is 4HI and mine is in 2WD. You conceivably go around that turn without your VSC engaging. Pretty sure my VSC will engage at 35 mph in 2WD on a snowy curve lol. Now if I put mine in 4WD we are operating on the same playing field. Understand?

Pretty sure your next set of questions will be something like "What are the drawbacks of having a full time 4WD?"
Glad you asked. Pretty much the only two drawbacks are efficiency and complexity. You will notice the LE has skinny 20" tires and a lower front fascia. This is needed to counteract the full time 4WD inefficiency and bring it up to the part time 4WD efficiency. If someone took a part time 4WD, put the LE's wheels and tires on it and added a lower front spoiler then it would get 1-2 additional mpg.
On the complexity issue you just have an additional component on the full time 4WD. Toyota is a very reliable vehicle and the chances of failing that component is slim but on the part time 4WD it is nil since it does not have it to start with.

Lastly, read my above post on driving in the rain. Cold does not matter unless it gets cold enough to freeze. If you have solid ice then nothing (4X4, full or part time) helps.

 

[Bruin1md]

1. You ( or the typical soccer mom) never have to worry if the roads get slick (with snow not rain) and
2. In specific situations, the full time 4WD (again, in mud or snow or dirt) will maintain tractive effort a bit longer before VSC and TRAC would kick in.

Let's say you take your full time 4WD around a snow covered corner at 35 mph. Now I am following close behind in my part time SR5 4WD. Yours is in standard mode which is 4HI and mine is in 2WD. You conceivably go around that turn without your VSC engaging. Pretty sure my VSC will engage at 35 mph in 2WD on a snowy curve lol. Now if I put mine in 4WD we are operating on the same playing field. Understand?

Pretty sure your next set of questions will be something like "What are the drawbacks of having a full time 4WD?"
Glad you asked. Pretty much the only two drawbacks are efficiency and complexity. You will notice the LE has skinny 20" tires and a lower front fascia. This is needed to counteract the full time 4WD inefficiency and bring it up to the part time 4WD efficiency. If someone took a part time 4WD, put the LE's wheels and tires on it and added a lower front spoiler then it would get 1-2 additional mpg.
On the complexity issue you just have an additional component on the full time 4WD. Toyota is a very reliable vehicle and the chances of failing that component is slim but on the part time 4WD it is nil since it does not have it to start with.

Lastly, read my above post on driving in the rain. Cold does not matter unless it gets cold enough to freeze. If you have solid ice then nothing (4X4, full or part time) helps.

You are a wealth of knowledge Greg-- I want you to know how much a newbie to 4WD vehicles appreciates yours and others' feedback and education on this forum.
As a fyi, I've never owned a new car (all have been bought used). So between the idea of buying a new car for the first time, and my forray into the world of 4WD SUV's, I've been pretty excited researching and driving these trucks.
I was actually considering a Nissan Xterra Pro4X as well--but it seems for all you get in the Trail edition (comparing the Xterra to this model alone), it's worth spending the extra $$ on the 4runner.

Regarding your example set forth in paragraph 2, yes I do/did understand how putting your SR5 in 4WD puts you on equal footing (so to speak) with the full time 4WD on the limited.
Where I was confused was that by engaging your part time 4WD (presumably in 4Hi), your transfer case is locked, so doesn't that limit your ability to turn SAFELY around those hypothetical curvy snowy roads relative to the limited in front of you?
Second, I did not realize that VSC is such a valuable tool and works so effectively when the Trail or SR5 is left in 2WD mode. That alone--based on what you've said in the above post-- seems to be all one really needs for most heavy rain conditions in that case.

 

[phillyd2]

Let me put a fork in this once and for all. Real American men buy the Limited. :usa2:

 

[Bruin1md]

1. You ( or the typical soccer mom) never have to worry if the roads get slick (with snow not rain) and
2. In specific situations, the full time 4WD (again, in mud or snow or dirt) will maintain tractive effort a bit longer before VSC and TRAC would kick in.

Let's say you take your full time 4WD around a snow covered corner at 35 mph. Now I am following close behind in my part time SR5 4WD. Yours is in standard mode which is 4HI and mine is in 2WD. You conceivably go around that turn without your VSC engaging. Pretty sure my VSC will engage at 35 mph in 2WD on a snowy curve lol. Now if I put mine in 4WD we are operating on the same playing field. Understand?

Pretty sure your next set of questions will be something like "What are the drawbacks of having a full time 4WD?"
Glad you asked. Pretty much the only two drawbacks are efficiency and complexity. You will notice the LE has skinny 20" tires and a lower front fascia. This is needed to counteract the full time 4WD inefficiency and bring it up to the part time 4WD efficiency. If someone took a part time 4WD, put the LE's wheels and tires on it and added a lower front spoiler then it would get 1-2 additional mpg.
On the complexity issue you just have an additional component on the full time 4WD. Toyota is a very reliable vehicle and the chances of failing that component is slim but on the part time 4WD it is nil since it does not have it to start with.

Lastly, read my above post on driving in the rain. Cold does not matter unless it gets cold enough to freeze. If you have solid ice then nothing (4X4, full or part time) helps.

One more thing-- the corrolary to the above is that if I went with a limited, and changed out the wheels/tires to a TRD pro package, it sounds like I can expect to get another couple of miles knocked off the expected MPG ............. ciest la vie.
But the trade off on the positive front would be less body roll on turns and dealing with potholes-- hopefully.

Does the limited require any lift/mods to accomodate the TRD pro wheel/tire package as is? It didn't sound that way based on those tires being 265's, but just double checking.

 

[1engineer]

You are a wealth of knowledge Greg-- I want you to know how much a newbie to 4WD vehicles appreciates yours and others' feedback and education on this forum.
As a fyi, I've never owned a new car (all have been bought used). So between the idea of buying a new car for the first time, and my forray into the world of 4WD SUV's, I've been pretty excited researching and driving these trucks.
I was actually considering a Nissan Xterra Pro4X as well--but it seems for all you get in the Trail edition (comparing the Xterra to this model alone), it's worth spending the extra $$ on the 4runner.

Regarding your example set forth in paragraph 2, yes I do/did understand how putting your SR5 in 4WD puts you on equal footing (so to speak) with the full time 4WD on the limited.
Where I was confused was that by engaging your part time 4WD (presumably in 4Hi), your transfer case is locked, so doesn't that limit your ability to turn SAFELY around those hypothetical curvy snowy roads relative to the limited in front of you?
Second, I did not realize that VSC is such a valuable tool and works so effectively when the Trail or SR5 is left in 2WD mode. That alone--based on what you've said in the above post-- seems to be all one really needs for most heavy rain conditions in that case.

Thanks. In bad weather, VSC is THE MAIN safety feature besides ABS. 4WD is a distant 3rd.
On the part time 4WD around snowy curves: No problems. A tire will just slip a bit is all, just like the full time 4WD.

You have to remember that your four tires never end up going the same distance on a trip. If you went around the proverbial block the outside tires would go further than the inside radius tires. Also, since your car steers from the front the rear of the vehicle turns in a smaller radius than the front. So going around the block will result in all four tires traveling several revolutions apart! Now, if you hook the front to the rear (4WD) something's got to give and that usually is a tire either sliding a bit or spinning a bit. That is why in HI only one on front and one on the rear is driving.

 

[philsey]

Let me put a fork in this once and for all. Real American men buy the Limited. :usa2:

Where were you 9 pages ago, hmmm?

 

[Bruin1md]

Let me put a fork in this once and for all. Real American men buy the Limited. :usa2:

So what does that say for all the non real American men who love their SR5's and Trail's on this forum?

lol

 

[03_4x4Runner]

You are a wealth of knowledge Greg-- I want you to know how much a newbie to 4WD vehicles appreciates yours and others' feedback and education on this forum.
As a fyi, I've never owned a new car (all have been bought used). So between the idea of buying a new car for the first time, and my forray into the world of 4WD SUV's, I've been pretty excited researching and driving these trucks.
I was actually considering a Nissan Xterra Pro4X as well--but it seems for all you get in the Trail edition (comparing the Xterra to this model alone), it's worth spending the extra $$ on the 4runner.

Regarding your example set forth in paragraph 2, yes I do/did understand how putting your SR5 in 4WD puts you on equal footing (so to speak) with the full time 4WD on the limited.
Where I was confused was that by engaging your part time 4WD (presumably in 4Hi), your transfer case is locked, so doesn't that limit your ability to turn SAFELY around those hypothetical curvy snowy roads relative to the limited in front of you?
Second, I did not realize that VSC is such a valuable tool and works so effectively when the Trail or SR5 is left in 2WD mode. That alone--based on what you've said in the above post-- seems to be all one really needs for most heavy rain conditions in that case.

If you do not want to give any thought about when to use 4x4 and know it is there all the time without your input get the limited. You will not have to try to train your wife about how to use the system and worry about her leaving it in 4x4 on dry pavement. If you ever have to pull out on a road from a gravel/slick or icy driveway quickly and worry about the tires spinning on the gravel while traffic bears down on you get the limited. It just goes just like it is on pavement. If none of these conditions apply to you the manual 4x4 will be fine.

 

[Dexter Morgan]

How much do you slip in the rain? Typical values of coefficient of adhesion (mu) of a rubber tire on asphalt (concrete is slightly higher) is around 0.8 for dry conditions and around 0.6 for wet asphalt. Compare that to 0.2 for hard pack snow and 0.1 for ice. Bottom line in traction situations wet pavement is not bad.
If you have an AWD vehicle like a Subaru or even a partial AWD vehicle like a CR-V the AWD does not even engage (CR-V) and the Subaru won't detect any slip in normal driving conditions.

The key is VSC and TRAC along with ABS. These electronic aids will keep you pointed in the right direction regardless of how many tires are pulling or pushing and Toyota's VSC system is very good.


Now, I'm 6'4" and I fit just fine...with a sunroof in the 5th gen 4Runner. I suggest you test it out and adjust the seat a bit. I have about an inch between my head and the sunroof surround.

My thoughts to 4wd in the rain pertain to situations on inclines from a stop where I need to get out in a hurry.

I might re-try a Limited with the roof, but when I sat in it, the sliding portion was ok but once my head went near the headliner outside of the sliding panel, it would graze...so annoying. And I'm not doing the seat lean as I did in my 4th gen (which was great in every other aspect by the way).

 

[M1911]

My thoughts to 4wd in the rain pertain to situations on inclines from a stop where I need to get out in a hurry.

I might re-try a Limited with the roof, but when I sat in it, the sliding portion was ok but once my head went near the headliner outside of the sliding panel, it would graze...so annoying. And I'm not doing the seat lean as I did in my 4th gen (which was great in every other aspect by the way).

In those situations the Limited does have an advantage.

Did you adjust the seat bottom height? It is adjustable up and down.