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Going in 4WD over 45 mph

KrispyKotex

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On my JK, I could shift into 4H at 55mph and have no issues. On the JL, you have to drop under 45mph. It’s harder shifting into 4H on the JL, so I normally drop to under 30mph. I understand you might be on an interstate and dropping speed might be dangerous, but the JL should be under 45. Also as mentioned, 4wd only helps with accelerating off the line, after that you’re just like any other vehicle. Jeep’s usually have more aggressive tires, so it may help a bit more, but you’re still braking and potentially skidding like everyone else.
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Oldbear

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My wife used to be a big Subaru fan, and I think the biggest takeaway, for me, from experiencing the Subaru enthusiast ethos was that by and large, people don't grasp the fact that AWD and 4WD only assist in acceleration. Those systems do NOTHING for stopping, and stopping is FAR more important. The attitudes of the Subaru guys were that they could do whatever they wanted in bad weather because they had AWD...they acted as if their cars ran on magic.
Which is exactly why you find them (and other 4wd’s) in the ditch. Back in my TJ days I pulled a LOT of 4wd vehicles out of the ditch or median strip. More than a few of them had passed me at speed a few miles prior😏
 

mackh4x0r

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Why are you going 70 mph on an interstate during a snowstorm? If you need 4wd drive, you shouldn't be going that fast. And Jeeps are made for off-roading not speeding 70 mph down the interstate in 4wd drive.
 

Traktor31

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My wife used to be a big Subaru fan, and I think the biggest takeaway, for me, from experiencing the Subaru enthusiast ethos was that by and large, people don't grasp the fact that AWD and 4WD only assist in acceleration. Those systems do NOTHING for stopping, and stopping is FAR more important. The attitudes of the Subaru guys were that they could do whatever they wanted in bad weather because they had AWD...they acted as if their cars ran on magic.
As a current Subaru owner, hubris is never good especially when operating a large metal object that injure or kill someone. Even with my Outback I take winter hazardous roads cautiously, give people room, and be on the defense.

I will say though, its the best vehicle I have ever owned in the snow, and thats even with my stock tires that are nothing to write home about. It's a beast in the snow and the full time AWD system is definitely awesome. Of course you are right though, if youre on ice? AWD aint stopping you from sliding around.

It will be interesting if I am able to get into the Wrangler to compare the two, Selec-trac is an option I really want, just depends if I go with a Sport or Sport S, since its not available on the Sport.
 

jellis4148

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Ok, lets just ask the main question. Why?!?! Why would you be in a situation where you're doing 70 and need to pull into 4wd? Conditions will slowly get worse, and you should be slowing down before you "need" 4wd. For the ones that say they were in Full-time, or AWD. That is a complete different system that uses clutches in the transfer case to allow slippage on non-slick surfaces so you don't destroy your hubs or 4wd system. I am not a fan of Auto 4wd. I've seen several people that don't understand it, and use it wrong only to need a new transfer case at 80,000 miles. If I'm driving 70, and the roads slowly start getting worse. My speed will slowly go down. 4wd doesn't mean drive fast on slick roads. I love the people that pass me when I'm keeping with the flow of traffic in a foot of fresh powder cause they have 4wd. It's even better when they are in the ditch farther down the road.
 

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Ok, lets just ask the main question. Why?!?! Why would you be in a situation where you're doing 70 and need to pull into 4wd? Conditions will slowly get worse, and you should be slowing down before you "need" 4wd. For the ones that say they were in Full-time, or AWD. That is a complete different system that uses clutches in the transfer case to allow slippage on non-slick surfaces so you don't destroy your hubs or 4wd system. I am not a fan of Auto 4wd. I've seen several people that don't understand it, and use it wrong only to need a new transfer case at 80,000 miles. If I'm driving 70, and the roads slowly start getting worse. My speed will slowly go down. 4wd doesn't mean drive fast on slick roads. I love the people that pass me when I'm keeping with the flow of traffic in a foot of fresh powder cause they have 4wd. It's even better when they are in the ditch farther down the road.
Exactly.

I still say you'd have a tough time illustrating a situation in which it is even remotely safe to drive 70mph (or 60mph even) and you NEED 4WD. If you can hit that speed and not get out of control, you do not need 4WD.
 

jellis4148

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I believe select-trac/Auto 4wd has its place. I just won’t use it. Like is said, it sides clutches and all you’re doing is wearing them out. Using it occasionally doesn’t hurt anything. I e had customers trade there vehicles in and they left them in Auto, and several of them needed new t-cases. To me that is something that’s going to wear out if used a lot.
 

Heimkehr

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I believe select-trac/Auto 4wd has its place. I just won’t use it. Like is said, it sides clutches and all you’re doing is wearing them out. Using it occasionally doesn’t hurt anything.

I e had customers trade there vehicles in and they left them in Auto, and several of them needed new t-cases. To me that is something that’s going to wear out if used a lot.
What vehicles?

My Honda Ridgeline used an on-demand VTM-4 system, as it was called. It engaged 4WD as driving (traction) conditions required, meaning its permanent operating condition was "Auto". I could also manually lock the front and rear axles, creating a 50/50 torque split, but only in Low 1, Low 2 or Reverse, and automatic disengagement occurred at ~18 mph. The VTM-4 design uses left- and right-side clutches.

Just curious to know what trade-ins were so delicate that a core drivetrain feature couldn't be used in set-it-and-forget-it mode.
 

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MrKnowitall

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Funny how it is always the Audis, Mercedes and BMWs that end up in the ditch. Even the ones with “AWD” slapped on the trunk.

They seem to forget those expensive Nurburgring-rated tires do squat the moment it gets a little cold.
That’s why Germans have a set of winter tires, often as a factory option.
 

jellis4148

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What vehicles?

My Honda Ridgeline used an on-demand VTM-4 system, as it was called. It engaged 4WD as driving (traction) conditions required, meaning its permanent operating condition was "Auto". I could also manually lock the front and rear axles, creating a 50/50 torque split, but only in Low 1, Low 2 or Reverse, and automatic disengagement occurred at ~18 mph. The VTM-4 design uses left- and right-side clutches.

Just curious to know what trade-ins were so delicate that a core drivetrain feature couldn't be used in set-it-and-forget-it mode.
[/QUOTE
I’ve seen plenty of the delicate Honda “Car with a bed” rigdeline need those clutches replaced just like any vehicle with that system. It also didn’t use the system the whole time it was driving like if you left a truck or Jeep in Auto 4wd. Doing that means the clutches in the transfer case are slipping the whole time the left it in. That means 60,000, 80,000, or 100,000 miles of wear. The Honda only engages if needed. The rest of the time it is in front wheel drive. So out of 100,000 miles it may only be using those rear clutches 20% of the time.
 

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I never understand why people dont just answer the simple question. Yes, you can drive over 45 in 4H. I could give a crap if anyone wants to go faster than I think they should in snow. Cracks me up. But Im from Jersey so maybe thats it. Lol
 

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Anyone suggest when to put into 4hi when roads are slightly snowy/wet? We have chain controls that require 4WD, but often the roads are just wet for a few miles. Should I just ignore the checkpoint and stay in 2wd until the roads are snow covered, or is 4hi not going to hurt anything?
 

wibornz

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If you're going 70 mph in a snowstorm, you're in the running for a Darwin award.
Or you live in Michigan. You might be crazy to run 70 in a snow storm in November...... By February, it is just another day and you are running 70 mph in snow storm yelling get the fuck out of the way when someone is driving slow.
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