Pin 7 mod in snow and ice (no lockers)? (1 Viewer)

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What nobody has addressed previously, the lower the effective gear (higher ratio) be it high or low range the more easily you will get wheel spin. For the best traction you want to be in 2nd gear versus 1st gear to avoid the wheel spin. This is exactly why the A343 transmission has the 2nd start button. It is easier to feather the throttle to avoid spin in a higher gear.
hey man. i’m putting it together here. slowly and with a lot of help.
two here please.
what is the difference between starting in 2nd at the transmission and “2nd start” and say starting in L at the transmission and in 2nd start. 2nd start starts in first and /then/ has to shift to 2nd and L would start in first and stays in first (which is basically what 2nd start does?)?
but if you use 2nd start you can keep it in Drive so you are not manually shifting out of first or second if you use L or 2nd at the transmission to get going?
also, i never quite got that 4Hi was 1:1 at the output shaft but 4Lo reduced the gearing at the output shaft. i just never tracked this. anyway.
what exactly is the difference between being in D and 4Lo and being in 2nd and 4Hi. meaning if you were on a bunch of switchbacks or on a steep hill with a sharp turn uphill or downhill in the mountains would you prefer one or the other?
 

ppc

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This applies to the 95-97 model years....
As you stated placing the shift lever in "2", with "2nd start" OFF the vehicle starts in 1st then shifts to second but will not shift into D.
The shift lever in "2", with "2nd start" ON the vehicle starts in 2nd but will not shift into D.
The shift lever in "D", with "2nd start" ON the vehicle starts in 2nd but will upshift into D.

High are low range just change overall gear ratios. Lower ratios (higher gear) provide less torque and therefore less chance of wheel spin in slippery conditions but also less capable of climbing steep hills.

Don't overthink things it's not rocket science. Drive around in high and low range, observe the tachometer and speedometer in different gears.
 
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Unlike your Tacoma, the 80 is full-time 4WD. That's why it has the CDL and viscous coupler. The VC provides the slip that you don't get when on the road in a part-time 4WD if you shift the Tacoma TC from 2 High to 4 High. There is no equivalent to 2 High in the 80 series TC, which may be where this confusion starts.

Of course, if you got stuck by slippery stuff under one end of the truck, then you'd hopelesslly spin your wheels there and the truck doesn't go. That's where the CDL comes in. It does what your Tacoma does where you switch into either 4 High or 4 Low and it locks the drivetrain together front and rear, splitting the torque 50/50 front to rear. But you also have the VC in the 80 which can split the torque a variable amount between the front and rear wheels. Which you want to use on snow and ice varies, Just be careful until you're comfortable with the CDL locked. With the CDL locked, it operates equivalent to the 50/50 split of of the part-time case.
thanks. i find the topic tough sledding so thanks for the help.
right so in the tacoma i can take it out of locked 4WD by putting it in 2Hi at the TC?
and in the LC it is always in AWD 60/40 because it has the (limited slip?) differential?
so the LC has the CDL and the tacoma has the manual front hubs basically is that it?
also, “part time case” implies when a limited slip differential with a locker? basically?

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This applies to the 95-97 model years....
As you stated placing the shift lever in "2", with "2nd start" OFF the vehicle starts in 1st then shifts to second but will not shift into D.
The shift lever in "2", with "2nd start" ON the vehicle starts in 2nd but will not shift into D.
The shift lever in "D", with "2nd start" ON the vehicle starts in 2nd but will upshift into D.

High are low range just change overall gear ratios. Lower ratios (higher gear) provide less torque and therefore less chance of wheel spin in slippery conditions but also less capable of climbing steep hills.

Don't overthink things it's not rocket science. Drive around in high and low range, observe the tachometer and speedometer in different gears.
thanks. in the tacoma i guess you can shift into 4hi from 4lo. but you can’t shift from 4hi to 4lo (or N to 4Hi or N to 4Lo i guess?) on the fly? because they are straight cut gears and not “synchro” helical gears?
so same thing in the land cruiser? meaning if you think you might need 4Lo you need to start out in 4Lo since you can’t get into it while climbing or descending?
 
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what exactly is the difference between being in D and 4Lo and being in 2nd and 4Hi. meaning if you were on a bunch of switchbacks or on a steep hill with a sharp turn uphill or downhill in the mountains would you prefer one or the other?

The main difference is that in low range the transmission can go into lower gears which is helpful if things are steep or difficult (both uphill and downhill).

Low range also provides significant engine braking for the downhill sections, so much so that in 1st gear low range you can crawl down some fairly steep sections without touching the brakes.

The best thing for you would be to try out these ideas in real life to see how they actually work. You wont' hurt anything by being in the wrong gear and you can always stop and put it in low or high range if things are not going as smoothly as you like.
 
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Oh I know....everyone got sleet/ice BEFORE the snow fell. And then with enough traffic 'powder snow' becomes 'hard pack' which is just one step away from ice. We're all driving on the same thing. But I've put about 75 miles total (today and yesterday) in just what you posted and as long as you don't dig down to the ice....a bone stock Land Cruiser (with decent tires) will walk right up that.

I understand you are searching for answers and applaud you for that.

We can't always recommend the 'best' gear (transfer case or transmission) for you to use because conditions vary so much. But we can help provide you with certain 'knowledge tools' that will aid you in making the decisions.

At times it sounds confusing because some of the folks responding also have lockers/traction aiding devices in their differentials and that alone can dictate when (or when not) you might choose a certain combination.

But to keep it simple:

Your transmission has a range/set of gears that is separate from the Transfer Case. You have in ascending order Low, 2nd and Drive (and in some cases Overdrive). You ALWAYS have these gears to work with. As you are aware (when your transmission is in drive) the transmission automatically up-shifts to each higher gear as you gain speed and apply throttle. You can probably 'feel' it shifting through the gears.

So you know how that works. Your Transfer Case has two sets of gears. One provides 'high range' (what you normally drive in) and the other (if you select it) 'low range' which is typically used off-road for slower speeds.

The gears in your transmission remain unaffected...they are always the same ratio and will still shift from low to second then 3rd/drive (if you start with the trans in drive). BUT....in low range you have a mechanical advantage (higher gearing). Meaning your transfer case gears (in low range) are turning more times (per one revolution of the driveshafts than when in high range.

An analogy might be as with a Mountain Bike where you shift down into its lowest 'gear'. You are peddling like a MoFo (your feet are the transfer case) but it doesn't take much effort and the torque to rear wheel is greater.

As for your CDL (Center Diff Lock) that simply locks the front and rear outputs together and forces them to turn at exactly the same speed (no differentiation) so the torque from the engine is evenly split front to rear. This can be good or not so good depending on your needs and the situation.

But with the CDL button and the Pin 7 'mod' YOU can choose to engage it or disengage at any time, any speed, just about any situation.

There is more to know about your transmission....such as manually shifting to a lower gear, when the transmission will 'hold' that gear and when it won't. When any of that might be appropriate. Best thing to do at first....is simply find a place you can off-road, put your Tcase in low range and experience what it does compared to high range and all of this will begin to make sense to you.

One last thing you asked about. 2nd gear 'start' allows your transmission to start out in 2nd gear (less torque) rather than the lower 1st/low gear to help avoid spinning your tires on surfaces that have low traction (ice, hard pack snow, etc). That is all it does.
thanks a lot for that FK. i never opened any of these up and i guess i never really understood them. it’s part of the reason i’ve always wanted to go back to a manual.
anyway, one thing i mosses is that i can downshift on the fly by simply taking off the O/D button. so on the highway i imagine i can gear down by flicking the O/D button at the stick.
is the CDL where the 60/40 happens and also the center locking but the transfer case is eheee i am going on and out of 4hi, 4lo and N i guess?
also for some exceptional reason i never quite followed that 2nd is literally second gear and Low is literally first gear.
anyway, back to that hill.
you like 4Lo (or 4hi) in Drive and CDL locked (presumably with O/D off even though it is unlikely you would rev it that high)? or if you had one shot would you go with 4Lo in second and CDL? i mean assuming the driver knows how to drive on ice and snow...
 
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The main difference is that in low range the transmission can go into lower gears which is helpful if things are steep or difficult (both uphill and downhill).

Low range also provides significant engine braking for the downhill sections, so much so that in 1st gear low range you can crawl down some fairly steep sections without touching the brakes.

The best thing for you would be to try out these ideas in real life to see how they actually work. You wont' hurt anything by being in the wrong gear and you can always stop and put it in low or high range if things are going as smoothly as you like.
yeah. thanks as always Zack.
i’ve never taken this stuff apart so your explanation of the range helped a lot. i guess i never got that 4Lo changed the gearing on the output shaft and 4Hi was 1:1.
honestly - well i guess i never shift an automatic like i would shift a stick so i keep it in drive. and i only put it in 2nd or Low when i really am going into a hairy slippery downhill or something. so i never really understood 2nd and Low was available to both “ranges” really.
so say you took that hill in 4Lo and locked CDL in Drive and she slipped and rolled back at a high rate of speed about 1/3 of the way up.
i mean assuming nice constant acceleration and no jerky moves since you grew up - well since you took your drivers test in a foot and a half of snow wheeling it around and parking it front end into snowpack since there was no way you could do the parallel park for the guy doing the test?
i mean would you change it from locked CDL, 4Lo?
 
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There's no 60/40 going on (it slightly varies all of the time when the CDL is unlocked), and yes the gears 1,2,3,4 on an auto are the same idea as in a manual.

2nd gear start is just like putting your truck in 2nd gear when starting. Less torque because of the higher gear.

Now head out for a drive, try high range, low range, CDL, 2nd start, etc. etc..... and see what works best for you.
 
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There's no 60/40 going on (it slightly varies all of the time when the CDL is unlocked), and yes the gears 1,2,3,4 on an auto are the same idea as in a manual.

2nd gear start is just like putting your truck in 2nd gear when starting. Less torque because of the higher gear.

Now head out for a drive, try high range, low range, CDL, 2nd start, etc. etc..... and see what works best for you.
lol. this week in texas.
so, here is beverly skyline, ridgemore drive and beverly hills drive. all north facing downward slopes into a ravine. reports are that all three were in fact totally iced up.
beverly skyline (the one with the limestone wall) is apparently the steepest road in austin.
i’m told the blue garage is new because the one that was there before got taken out by a ambulance that lost it’s brakes.
everything was great while up in the hills until i took that left on westview!





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lol. this week in texas.
beverly skyline, ridgemore drive and beverly hills drive. north facing downward slopes into a ravine. all three were totally iced up.
beverly skyline (the one with the limestone wall) is apparently the steepest road in austin.
the blue garage is new because the one that was there before got taken out by a ambulance that lost it’s brakes.
everything was great while up in the hills until i took that left on westview!





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fun in the hills while it lasted!

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thanks. i find the topic tough sledding so thanks for the help.
right so in the tacoma i can take it out of locked 4WD by putting it in 2Hi at the TC?
and in the LC it is always in AWD 60/40 because it has the (limited slip?) differential?
so the LC has the CDL and the tacoma has the manual front hubs basically is that it?
also, “part time case” implies when a limited slip differential with a locker? basically?
The Tacoma is always "locked" iwhen shifted to 4WD because it has no VC/CDL. The driveline ties everything together front to rear through the transfer case, so there's always a 50/50 split, front to rear.

The 80's transfer case has the VC, which provides a variable split, front to rear, when the CDL is unlocked. When it is locked, then it operates like the TC in the Tacoma, splitting things 50/50.

The Tacoma's manual front hubs provide a way to take the drag of the turning front half of the driveline components out of the equation when in 2 Hi, saving gas and wear and tear. They don't directly correlate with anything on the US-spec 80 series.

A "part time case" is one like in your Tacoma. You have 4WD only part of the time, when shifted into 4 Hi or 4 Lo and the hubs are locked. Any locker or LSD for front or rear axles is optional. This is in contrast to the "full time case" that is in the 80 where AWD is always on.
 
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The Tacoma is always "locked" iwhen shifted to 4WD because it has no VC/CDL. The driveline ties everything together front to rear through the transfer case, so there's always a 50/50 split, front to rear.

The 80's transfer case has the VC, which provides a variable split, front to rear, when the CDL is unlocked. When it is locked, then it operates like the TC in the Tacoma, splitting things 50/50.

The Tacoma's manual front hubs provide a way to take the drag of the turning front half of the driveline components out of the equation when in 2 Hi, saving gas and wear and tear. They don't directly correlate with anything on the US-spec 80 series.

A "part time case" is one like in your Tacoma. You have 4WD only part of the time, when shifted into 4 Hi or 4 Lo and the hubs are locked. Any locker or LSD for front or rear axles is optional. This is in contrast to the "full time case" that is in the 80 where AWD is always on.
got it. /thanks/.
i see. so in the part time case in the taco shifting into 4hi or 4lo i guess drives the front driveshaft and the front axle. and the manual hubs lock the wheels to the axle i guess.
can i just also ask -
do you ever take off O/D to keep it in third in the LC - say when at speed on the highway? meaning you turn off O/D and basically downshift?
do you use CDL lock and/or 4hi/4lo gearing and/or put it in 2nd differently in some way going steep uphill as compared to going steep downhill. like say the million dollar highway in colorado or something. are you in one combination or another on an uphill as compared to a downhill for one reason or another?
i did see the manual wants you in Drive when towing uphill and not 2nd or first for some reason related to burning something up. but is there any difference in normal driving uphill as compared to downhill?
i hope you don’t mind. i try to ask the pros here questions when i get the chance...
 
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got it. /thanks/.
i see. so in the part time case in the taco shifting into 4hi or 4lo i guess drives the front driveshaft and the front axle. and the manual hubs lock the wheels to the axle i guess.
can i just also ask -
do you ever take off O/D to keep it in third in the LC - say when at speed on the highway? meaning you turn off O/D and basically downshift?
do you use CDL lock and/or 4hi/4lo gearing and/or put it in 2nd differently in some way going steep uphill as compared to going steep downhill. like say the million dollar highway in colorado or something. are you in one combination or another on an uphill as compared to a downhill for one reason or another?
i did see the manual wants you in Drive when towing uphill and not 2nd or first for some reason related to burning something up. but is there any difference in normal driving uphill as compared to downhill?
i hope you don’t mind. i try to ask the pros here questions when i get the chance...
I have taken O/D off when towing a heavy trailer when the transmission is shifting back and forth too much. Otherwise it never hurts to leave it on. It won't actually shift into that last gear (Overdrive) unless conditions are OK for it to do so.

I can't think of any situation where you would ever drive in Low on a highway - period. I might put it in 2nd going down a steep hill towing a load if conditions warranted a relatively slow speed and I wanted to use the engine to keep the speed slow as opposed to riding the brakes. Low is for off-road or for very short times when you need all the torque you can get (pulling a boat up a ramp or pulling up a shrub in your yard). It's not for the highway. I also wouldn't ever lock the CDL on dry pavement for very long. It's primarily for low traction situations (mud, snow, sand) or for off-road situations but predominately in Low.

If you tow and keep the transmission in D then it will automatically shift from first to second to drive as conditions warrant. You don't want to drive long distances at high RPMs in first or second or you could burn up the transmission or the engine for that matter.

If you don't know the difference between low and high range then please go find a quiet field or dirt road and drive in Low range for a few minutes. It will be obvious to you at that point that your speed in every gear has more less been cut in half at any given rpm (I don't recall the gear ratios so it might not be exactly half so don't hold me to that as an absolute).
 
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@leonard_nemoy i don’t get it. can’t you just ignore the thread? you have it set up to get alerted to every new post on the forum so it all hits your inbox? you accidentally subscribed to the thread? can’t you just set it to ignore a poster on your end?
 
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leonard_nemoy

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@leonard_nemoy i don’t get it. can’t you just ignore the thread? you have it set up to get alerted to every new post on the forum so it all hits your inbox? you accidentally subscribed to the thread? can’t you just set it to ignore a poster on your end?

Nothing to get, I am just bored and trolling while I drink my sunday morning coffee and contemplate my options for the day.

Like my grandpa always said, "turn up the heat, turn down the wire, let the pool form, and spread the love".........

Alright, honestly I might still be a little buzzed from too many pina colada's last night. 🍍🥥🍻
 

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