4H on the highway safe???

[ColoradoMike]

Hahahaha, so, as the OP said in his OP: A lot of really conflicting information!

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[Joaquim]

Hahahaha, so, as the OP said in his OP: A lot of really conflicting information!

You see what I’m getting at?

 

[ColoradoMike]

You see what I’m getting at?

Indeed. It's my least favorite aspect of my Wrangler. I love it in most ways, but really wish I had the 4H-auto option.

 

[Some Random Guy]

You see what I’m getting at?

Maybe there are 2 parts to this answer. Is it safe for your vehicle: Yes as long as you don’t do sharp curves with traction.
Is it safe at highway speeds: No, 4wd cannot help you stop any faster in poor traction than 2H and at full highway speed is insufficient to keep you on the road in dynamic conditions. Momentum is too much for 4H to overcome unless speeds are sufficiently slow (aka, not highway).

 

[Joaquim]

Indeed. It's my least favorite aspect of my Wrangler. I love it in most ways, but really wish I had the 4H-auto option.

I just talked to a shop that said they could put a factory 392 transfer case in to allow that AWD function

 

[Joaquim]

Maybe there are 2 parts to this answer. Is it safe for your vehicle: Yes as long as you don’t do sharp curves with traction.
Is it safe at highway speeds: No, 4wd cannot help you stop any faster in poor traction than 2H and at full highway speed is insufficient to keep you on the road in dynamic conditions. Momentum is too much for 4H to overcome unless speeds are sufficiently slow (aka, not highway).

Yeah but the types of turns I’m typically using 4H for are at around 60mph on I70 through vail pass or on roads like highway 40 to steamboat through winter storms - so very slight turns, nothing drastically quick

 

[ALK]

Yes, it's perfectly fine to use 4wd at hwy speeds, just remember it won't help you stop any quicker. You will feel if the system is getting to much grip. Things in life can be more about using common sense then what a book or manual will say.

 

[bjm00se]

...at around 60mph on I70 through vail pass or....

OK, I want to change my answer. If traction is good enough you're going 60mph, then as others said, it's 2H or AWD, not 4H.

I thought we were talking tire chain conditions, heavy snow and ice, and traffic moving 25-30mph.

 

[Some Random Guy]

Yeah but the types of turns I’m typically using 4H for are at around 60mph on I70 through vail pass or on roads like highway 40 to steamboat through winter storms - so very slight turns, nothing drastically quick

If you need 4H, you shouldn’t be going that fast. You will get lucky for a while, but not forever.

 

[ColoradoMike]

If you need 4H, you shouldn’t be going that fast. You will get lucky for a while, but not forever.

I think the issue is for mixed conditions. Sometimes you're going along (often in Colorado) and there has been snow, but this stretch of road is generally dry and 60MPH is PERFECTLY safe... and then all of the sudden, there's been some blowing snow and you need to slow down as you hit the snowy stretch... it sucks if you are in 2WD when this happens, and you need to shift into 4H as you get into the snow, and then you're past the blowing-snow section and back to mostly dry and 60 is safe again.
In an AWD car, these conditions are easy. With Jeep's part-time 4WD system, you are forced to make sub-optimal choices... i.e., driving way slower than you would need to if you were in a Subaru because you're in 2WD, or just constantly shifting back and forth sometimes suddenly and under stress.
That's why the T-cases that have all of the options: 2H, 4H, 4H-auto, and 4-Lo are best, and I wish they were the standard.
OP; it doesn't need to be a 392 t-case; you can order a 4:1 HD full-time sys with the options above for a regular roob and probably a Willys, I imagine. But as for aftermarket retro-fit... I don't know. I think John VanJeep was saying that these t-cases are also paired with different axle joints, etc...

 

[Joaquim]

I think the issue is for mixed conditions. Sometimes you're going along (often in Colorado) and there has been snow, but this stretch of road is generally dry and 60MPH is PERFECTLY safe... and then all of the sudden, there's been some blowing snow and you need to slow down as you hit the snowy stretch... it sucks if you are in 2WD when this happens, and you need to shift into 4H as you get into the snow, and then you're past the blowing-snow section and back to mostly dry and 60 is safe again.
In an AWD car, these conditions are easy. With Jeep's part-time 4WD system, you are forced to make sub-optimal choices... i.e., driving way slower than you would need to if you were in a Subaru because you're in 2WD, or just constantly shifting back and forth sometimes suddenly and under stress.
That's why the T-cases that have all of the options: 2H, 4H, 4H-auto, and 4-Lo are best, and I wish they were the standard.
OP; it doesn't need to be a 392 t-case; you can order a 4:1 HD full-time sys with the options above for a regular roob and probably a Willys, I imagine. But as for aftermarket retro-fit... I don't know. I think John VanJeep was saying that these t-cases are also paired with different axle joints, etc...

Yeah this is exactly my issue - the conditions vary constantly so it’s often inconvenient to switch from 2 to 4H (so I often just leave it in 4H) - do all rubicons have the AWD function?? And also I’m planning on switching out the axles either way so I don’t think it’ll be too much of an issue

 

[Heimkehr]

If I'm using the transfer case, it's because conditions compel me to proceed at reduced speeds, period.

 

[GATORB8]

I think the issue is for mixed conditions. Sometimes you're going along (often in Colorado) and there has been snow, but this stretch of road is generally dry and 60MPH is PERFECTLY safe... and then all of the sudden, there's been some blowing snow and you need to slow down as you hit the snowy stretch... it sucks if you are in 2WD when this happens, and you need to shift into 4H as you get into the snow, and then you're past the blowing-snow section and back to mostly dry and 60 is safe again.
In an AWD car, these conditions are easy. With Jeep's part-time 4WD system, you are forced to make sub-optimal choices... i.e., driving way slower than you would need to if you were in a Subaru because you're in 2WD, or just constantly shifting back and forth sometimes suddenly and under stress.
That's why the T-cases that have all of the options: 2H, 4H, 4H-auto, and 4-Lo are best, and I wish they were the standard.
OP; it doesn't need to be a 392 t-case; you can order a 4:1 HD full-time sys with the options above for a regular roob and probably a Willys, I imagine. But as for aftermarket retro-fit... I don't know. I think John VanJeep was saying that these t-cases are also paired with different axle joints, etc...

The axle shafts in those equipped with the full time case have cv’s instead of u joints.

I believe the 4:1 cases are only in the non 392 Rubicons. The 392 is 2.72:1.

 

[Joaquim]

If I'm using the transfer case, it's because conditions compel me to proceed at reduced speeds, period.

This is exactly the type of conditions I’m running 4H in - or to get over bigger curbs at the mall

 

[Some Random Guy]

I think the issue is for mixed conditions. Sometimes you're going along (often in Colorado) and there has been snow, but this stretch of road is generally dry and 60MPH is PERFECTLY safe... and then all of the sudden, there's been some blowing snow and you need to slow down as you hit the snowy stretch... it sucks if you are in 2WD when this happens, and you need to shift into 4H as you get into the snow, and then you're past the blowing-snow section and back to mostly dry and 60 is safe again.
In an AWD car, these conditions are easy. With Jeep's part-time 4WD system, you are forced to make sub-optimal choices... i.e., driving way slower than you would need to if you were in a Subaru because you're in 2WD, or just constantly shifting back and forth sometimes suddenly and under stress.
That's why the T-cases that have all of the options: 2H, 4H, 4H-auto, and 4-Lo are best, and I wish they were the standard.
OP; it doesn't need to be a 392 t-case; you can order a 4:1 HD full-time sys with the options above for a regular roob and probably a Willys, I imagine. But as for aftermarket retro-fit... I don't know. I think John VanJeep was saying that these t-cases are also paired with different axle joints, etc...

I suppose I view this as part of getting lucky. When I hit patches like that I reduce speed so I can better see them coming even when the road clears back up. If I go a few miles with no more issues, then I’ll speed back up.
That first second of hitting poor traction is all it takes to send you off the road, or into another vehicle. Even when I had an AWD Subaru I’d slow down. People would pass me, and it was not rare to find them in the ditch a few miles later.
I have no experience in Colorado though. It’s one of the 9 states I haven’t driven in/through yet.

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