scared to death

[Nos4r2]

Re: scared to death

Uh..... He's RWD. The ball on the back end does put the weight on the drive axle.

Ah. That chucks the yellow snow on my conflagration

Saying that, a front mounted towball on a 4x4 makes things a lot easier anyhow.

 

[newbie4life]

Re: scared to death

More sophisticated part or full-time "all wheel drive" systems, such as are found on GMC pickups and as an option on Jeep wagons, and on many cars, use either a center differential or a viscous coupling to eliminate the problem of drivetrain windup, and so can be used on dry pavement.

And Cadillac Escalade's and the Early (2003 - 2005) Silverado SS.

 

[dirtyoldman]

Re: scared to death

More sophisticated part or full-time "all wheel drive" systems, such as are found on GMC pickups and as an option on Jeep wagons, and on many cars, use either a center differential or a viscous coupling to eliminate the problem of drivetrain windup, and so can be used on dry pavement.

This is very true, but consult the owners manual to be sure. A broken transfer case and the resulting tow will not be cheap at all. My GMC for instance has part time 4wd. I can break it by turning on dry pavement in 4wd.

 

[EJ3]

Re: scared to death

I have a 15' bass type boat. I dont think it weighs a whole lot, but it sure is heavy when moving by hand in the garage!!

Anyways, I use my fathers "4bangger" Toyota Tacoma with manual trans and 2WD only. I have never had a problem with spinning tires or slipping on the ramp. I use the parking brake method to get me out. I back down the ramp pretty slow until the boat is close to floating then I pump the brakes to "nudge" the boat off. I am in and out of the ramp in 30 seconds or less.

My father on the other hand can't conquer the ramp with just the truck, no boat or trailer even attached!!! His last, and only, attempt almost ended up in a new clutch!!!! lol

 

[SuperNova]

Re: scared to death

This is very true, but consult the owners manual to be sure. A broken transfer case and the resulting tow will not be cheap at all. My GMC for instance has part time 4wd. I can break it by turning on dry pavement in 4wd.

That is because the two terms "part-time 4wd" and "full-time 4wd" are not interchangeable as starcraft67 used them. They describe two very different 4wd systems. Part time 4wd is meant to be used "part time"--mainly during slippery conditions. Full-time 4wd can be used all the time due to it being a clutched or electronically controlled 4wd engagement system that can allow the tires to rotate at different speeds while turning on dry pavement---which part time 4wd is not capable of.
--
Stan

 

[dirtyoldman]

Re: scared to death

That is because the two terms "part-time 4wd" and "full-time 4wd" are not interchangeable as starcraft67 used them. They describe two very different 4wd systems. Part time 4wd is meant to be used "part time"--mainly during slippery conditions. Full-time 4wd can be used all the time due to it being a clutched or electronically controlled 4wd engagement system that can allow the tires to rotate at different speeds while turning on dry pavement---which part time 4wd is not capable of.
--
Stan

Exactly!

 

[oops!]

Re: scared to death

I think I would be terrified to use the 2wd one.

I AM !!!!!

had to load the back with big rocks one time to get out. took me an hour.
(late at night, some times we dont get in till 2 am)

unless they fix the ramp or build a new launch, i think im gonna carry a winch.

 

[Nos4r2]

Re: scared to death

A lot of us over here using 2wd cars haul the boat up the ramp on a long rope to the towball. It keeps the car on the flat and makes it a lot easier to recover.

You do need someone on lookout for it though or some idiot will try and walk either behind the boat or over the towrope.

 

[starcraft67]

Re: scared to death

Further on the issue of part-time or full-time AWD: The reference I was making was to certain part-time systems in use on newer trucks and Jeeps that, like the full-time systems in cars, can be used all the time because of a center differential, but also can be shifted out of 4WD into 2WD just like the old traditional 4WD. The upgrade or optional system on the Jeep Grand Cherokee is like this, so is the system on newer GMC pickups. So these days, in addition to "full-time AWD" and the old-style "4WD not for use on dry pavement," there are vehicles that can be either 2WD or 4WD even on dry road.

 

[dirtyoldman]

Re: scared to death

Further on the issue of part-time or full-time AWD: The reference I was making was to certain part-time systems in use on newer trucks and Jeeps that, like the full-time systems in cars, can be used all the time because of a center differential, but also can be shifted out of 4WD into 2WD just like the old traditional 4WD. The upgrade or optional system on the Jeep Grand Cherokee is like this, so is the system on newer GMC pickups. So these days, in addition to "full-time AWD" and the old-style "4WD not for use on dry pavement," there are vehicles that can be either 2WD or 4WD even on dry road.

Thanks for clarifying. I was just worried someone might read what you wrote and say "hmm...I've got a GMC, I must be able to do this."

I believe that is only available on the lighter trucks.

 

[SuperNova]

Re: scared to death

Further on the issue of part-time or full-time AWD: The reference I was making was to certain part-time systems in use on newer trucks and Jeeps that, like the full-time systems in cars, can be used all the time because of a center differential, but also can be shifted out of 4WD into 2WD just like the old traditional 4WD. The upgrade or optional system on the Jeep Grand Cherokee is like this, so is the system on newer GMC pickups. So these days, in addition to "full-time AWD" and the old-style "4WD not for use on dry pavement," there are vehicles that can be either 2WD or 4WD even on dry road.

I appreciate what you are trying to say, but your terminology is incorrect. Regardless of whether it is on a car or a truck, there are "full-time 4wd", "part-time 4wd" and "AWD". Part-Time 4wd means it can only be used PART-TIME. Full-Time 4wd means it can be used ALL the time. And AWD means it's ALL-WHEEL DRIVE. Yes, some of the AWD's can be shifted into 2wd and some of the trucks have a part-time 4wd position as well as a full-time 4wd position and 2wd. Great---but it doesn't make the terms interchangeable.

 

[newbie4life]

Re: scared to death

What AWD vehicle can be shifted into 2WD without removing a driveshaft?

 

[SuperNova]

Re: scared to death

What AWD vehicle can be shifted into 2WD without removing a driveshaft?

Chevy Suburban 2001 has a Auto4wd position,4wd hi, 4wd lo and a 2wd position. Some Jeeps have AWD and also 2wd. Newer Durangos Have Awd, 4wd locked and 2wd. This is what I am talking about----the terms are interpreted incorrectly and used inaccurately. You need to read your owners manual to be sure what you have and how to use it--as stated before.
--
Stan

 

[newbie4life]

Re: scared to death

Chevy Suburban 2001 has a Auto4wd position,4wd hi, 4wd lo and a 2wd position. Some Jeeps have AWD and also 2wd. Newer Durangos Have Awd, 4wd locked and 2wd. This is what I am talking about----the terms are interpreted incorrectly and used inaccurately. You need to read your owners manual to be sure what you have and how to use it--as stated before.
--
Stan

It's not just the 2001 'Burbans... it's most GM trucks (with the exception of the Denali GMC, Cadillac Escalades, and Silverado SS which are truly AWD vehicles) from that point (actually, I believe it's even earlier... like around '99 -- the new body style, not the '99 classics) on that has Auto 4wd (which is NOT AWD), 4hi, 2hi, and 4lo.

So, if I'm understanding correctly -- One could go out and buy a New Durango, with AWD, 4wd and 2wd -- all in the same single vehicle.

 

[reellittlephish]

Re: scared to death

2 years ago, I had a partner "smoke" my manual clutch pulling my 97 Skeeter out. Now, glazed, the clutch is easier to burn. I often use the 4x4 function on the Toyota Tacoma if the ramp is steep, wet or gravel. Having a tachometer to watch may help someone learning. The parking brake maneuver is also something I use.

 

[SuperNova]

Re: scared to death

It's not just the 2001 'Burbans... it's most GM trucks (with the exception of the Denali GMC, Cadillac Escalades, and Silverado SS which are truly AWD vehicles) from that point (actually, I believe it's even earlier... like around '99 -- the new body style, not the '99 classics) on that has Auto 4wd (which is NOT AWD), 4hi, 2hi, and 4lo.

So, if I'm understanding correctly -- One could go out and buy a New Durango, with AWD, 4wd and 2wd -- all in the same single vehicle.

How do you think Auto 4wd works???

If you read about the "Auto 4wd" and how it works it is most certainly an AWD system. There is a clutch inside the transfer case that is used to drive the front driveshaft in auto 4wd. The front axles are also engaged to the differential at all times while in auto 4wd. The clutch is what allows the front to rear speed differential to occur while turning. In regular 4wd hi or lo the clutch is overridden, the front driveshaft is turned by a gear (instead of a clutch) so no slip can occur in the transfer case between the front and rear driveshafts.

Just as a side note: There are about as many different versions of AWD and how it is acclomplished as there are manufacturers so your "true AWD" is open to discussion. The only "True AWD" has to have the center diff capable of locking and the front and rear diffs both have to be capable of equal torque distribution (locking). A lot of vehicles that claim to be "AWD" are actually just selective 2wd. Volvo is about the only one I know firsthand that comes close to equal torque distribution to all 4 wheels (they use the ABS and TRACS systems to equalize torque on the front wheels and an electronically controlled power transfer unit to distribute front to rear with a locking diff in the rear.) But even this is not a "true" AWD.

Yes, you can most certainly buy a new Durango with AWD, 4wd and 2wd. It is based on the transfer case. Not all have it. I have 3 in the shop right now that I just checked and 2 are AWD and 4WD Locked and the third has AWD, 4wd hi, 4wd lo and 2wd.

I also was aware that other GM models had the same 4wd features as my '01 Suburban, but I felt one example was enough.

Lastly, I would submit that a lot of the terms used to denote different systems are nothing more than marketing hype. After all, aren't All-Wheel Drive ( 4 wheels driven) and 4-wheel drive (4 wheels driven)mean essentially the same thing? Granted, there is part-time and full time 4wd, but basically you are driving ALL 4 wheels.
--
Stan

 

[newbie4life]

Re: scared to death

How do you think Auto 4wd works???

If you read about the "Auto 4wd" and how it works it is most certainly an AWD system. There is a clutch inside the transfer case that is used to drive the front driveshaft in auto 4wd. The front axles are also engaged to the differential at all times while in auto 4wd. The clutch is what allows the front to rear speed differential to occur while turning. In regular 4wd hi or lo the clutch is overridden, the front driveshaft is turned by a gear (instead of a clutch) so no slip can occur in the transfer case between the front and rear driveshafts.

Just as a side note: There are about as many different versions of AWD and how it is acclomplished as there are manufacturers so your "true AWD" is open to discussion. The only "True AWD" has to have the center diff capable of locking and the front and rear diffs both have to be capable of equal torque distribution (locking). A lot of vehicles that claim to be "AWD" are actually just selective 2wd. Volvo is about the only one I know firsthand that comes close to equal torque distribution to all 4 wheels (they use the ABS and TRACS systems to equalize torque on the front wheels and an electronically controlled power transfer unit to distribute front to rear with a locking diff in the rear.) But even this is not a "true" AWD.

Yes, you can most certainly buy a new Durango with AWD, 4wd and 2wd. It is based on the transfer case. Not all have it. I have 3 in the shop right now that I just checked and 2 are AWD and 4WD Locked and the third has AWD, 4wd hi, 4wd lo and 2wd.

I also was aware that other GM models had the same 4wd features as my '01 Suburban, but I felt one example was enough.

Lastly, I would submit that a lot of the terms used to denote different systems are nothing more than marketing hype. After all, aren't All-Wheel Drive ( 4 wheels driven) and 4-wheel drive (4 wheels driven)mean essentially the same thing? Granted, there is part-time and full time 4wd, but basically you are driving ALL 4 wheels.
--
Stan

I guess I know nothing. But here's what I have for experience with this:

With my Silverado SS, if I hit the gas in snow or on ice (or any other time, for that matter), I have grip right now. If I hit the gas on a regular 4wd (I've owned 2 others, and my dad has owned 2 since the auto 4wd feature) silverado in the same situation, with auto 4wd engaged, it spins for a tenth of a second, then grabs like you can't imagine. It senses when 4wd is warranted, and then locks it in. This is NOT what you want to use when you definately need 4wd. It's the setting that you use when the weather is inclemental, and the roads are questionable. If you know you need it, just put it in 4wd.

As for 4wd, I was taught that you do NOT have 4 of them driving (with the exception of a few models, Jeep with the old quadra-trac being one of them). Without Posi, you'll have 1 on each axle, while with posi, you will have 1 on the front axle, and both the rears.

 

[Nandy]

Re: scared to death

I have only needed 4wd to get out of a "ramp" once, but I needed it baddd! However, it was my fault. I have a 2005 4runner and a 1998 chevy blazer and I dont use the 4wd on either while launching or retrieving my Babcock.

 

[SuperNova]

Re: scared to death

I guess I know nothing. But here's what I have for experience with this:

With my Silverado SS, if I hit the gas in snow or on ice (or any other time, for that matter), I have grip right now. If I hit the gas on a regular 4wd (I've owned 2 others, and my dad has owned 2 since the auto 4wd feature) silverado in the same situation, with auto 4wd engaged, it spins for a tenth of a second, then grabs like you can't imagine. It senses when 4wd is warranted, and then locks it in. This is NOT what you want to use when you definately need 4wd. It's the setting that you use when the weather is inclemental, and the roads are questionable. If you know you need it, just put it in 4wd.

As for 4wd, I was taught that you do NOT have 4 of them driving (with the exception of a few models, Jeep with the old quadra-trac being one of them). Without Posi, you'll have 1 on each axle, while with posi, you will have 1 on the front axle, and both the rears.

I don't know which system you have on your Silverado SS, but there are way too many variables that affect traction (grip) to make a subjective comparison.
Some Chev and Gmc trucks have a Posi-Traction rear and some have a locking rear and some have an open rear and this may be the difference you experienced. With the lockers you have to spin one tire a bit before the locking mechanism engages the other tire. It's based on a centrifugal weight set-up that only sees centrifugal force when one tire is spinning at a somewhat higher speed than the other tire. So you HAVE to spin one tire a little before the locker will engage, thus your 10 second lag. A Posi-Traction, on the other hand, has clutches in the rear diff carrier that keep both axles tied together at all times up to a certain ft/lb yield value (usually about 400 ft/lbs) at which point one tire is able to spin faster than the other. So you can see how one system would react differently than the other on initial acceleration in slippery conditions. I think your SS has a Posi instead of a locking carrier in the rear.

The Auto 4wd doesn't "sense" anything it has no sensors other than for the position of the shift fork and it doesn't communicate with any of the other modules. All it knows is which button you pushed and where the shift fork is. It engages the disconnect for the front axle(which is mounted out on the right axle shaft) and it puts the transfer case into a "clutched 4WD". The clutch allows the vehicle to negotiate turns on dry pavement while driving the front and rear axle. You can overcome the clutch with sufficient torque just like a clutched rear differential. Auto 4WD is exactly the same as AWD on a car.

Dodge and Jeep use the exact same transfer cases as GM and Chevrolet. They are all New Process cases and the number details the features. there are NP231, NP241, NP242 and so on and so forth. The first number denotes the speeds (2= 2 speeds--High and Low), the second number denotes the load rating with a higher number being stronger and the last number denotes whether it's electrically shifted or manually as well as whether it has the clutch for AWD/4WDAuto.

As far as 4WD not really being 4WD, but rather selective 2WD I agree wholeheartedly. I said as much in my second paragraph. But the same is true of AWD. The only way to have true AWD/4WD is to lock the front and rear axles together as well as the left and right sides of the axles. Unfortunately, in the real world, vehicles need to negotiate corners and a fully locked 4wd system just can't cope with corners and the associated wheel speed differences needed. So the engineers designed compromises that do the best they can for all situations. That's why there are so many different types of 4wd/awd systems. The names are just marketing ploys designed to differentiate one manufacturers system from anothers while trying to make it sound like it does the job better.

 

[newbie4life]

Re: scared to death

The Auto 4wd doesn't "sense" anything it has no sensors other than for the position of the shift fork and it doesn't communicate with any of the other modules. All it knows is which button you pushed and where the shift fork is. It engages the disconnect for the front axle(which is mounted out on the right axle shaft) and it puts the transfer case into a "clutched 4WD". The clutch allows the vehicle to negotiate turns on dry pavement while driving the front and rear axle. You can overcome the clutch with sufficient torque just like a clutched rear differential. Auto 4WD is exactly the same as AWD on a car.

So if what you're saying is true, then there's no difference between Auto 4wd, and 4HI. Guess you should let GM know, because they seem to think they needed an extra button.

In fact, here's what GM says about their auto trac transfer case:

"Light transfer case assemblies with aluminum housings and optimized low-range gears and electronic shift controls with reliable contactless sensors help the available Autotrac active transfer case in Silverado 1500 4x4 models to better adjust to varying road conditions. The Autotrac system features four drive modes (2HI, AUTO/4WD, 4HI and 4LO) plus a neutral setting.

-2HI provides the most efficient driving mode.
-When engaged, AUTO/4WD detects rear-wheel slippage and automatically shifts into 4WD as road conditions dictate.
-4HI helps handle snow, ice, rain and most off-road conditions.
-4LO helps handle extreme conditions, such as steep hills, deep sand, mud and snow. "


I thought you said it 'doesn't "sense" anything'?????