Wife drove in 4L for 20 Miles at 60 miles per hour.

[AnnDee4444]

FWIW: The amount of bind should be somewhat proportional (exponential?) to the steering angle. Driving at 60 MPH typically doesn't result in high steering angles.

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[Bruce Willys]

FWIW: The amount of bind should be somewhat proportional (exponential?) to the steering angle. Driving at 60 MPH typically doesn't result in high steering angles.

How does one get on and off the freeway without turning?

 

[AnnDee4444]

How does one get on and off the freeway without turning?

Calm down, I'm not arguing with you.

 

[Bruce Willys]

Calm down, I'm not arguing with you.

I am calm, nothing personal. Sorry if I offended you with my response, that wasn't my intention.

 

[OSCAR II]

Yeah no, people don’t shear axle shafts on the street.

Maybe not but they sure break a lot of front driveshafts! Yokes, u joints, CV joints, slip joint splines I've rebuilt or replaced many on vehicles that have never been wheeling. I don't think most have ever seen any dirt.

 

[Zandcwhite]

How does one get on and off the freeway without turning?

You don’t actually believe that a quarter turn of the wheel on a clover leaf is the same angle as full lock off road do you? Drifters rarely break axle shafts as a tire at street pressure has far less traction period. An aired down tire, pinned between 2 rocks, is going to exert far more torque, bind, and load on the entire drivetrain than is physically possible on the street cruising around. Apply the same torque on road and the tire/ tires spin every time. As carol shelby said, there’s no such thing as too much horsepower, just not enough traction. In this discussion the opposite is true. In 8th gear on the freeway you have a .67 reduction in torque. Your 280 ftlbs becomes 187 before it gets to the tcase. Less torque in is easier on parts. The hardest you’ll ever be on your drivetrain is 1st gear, low range, full lock, axles locked, with lots of traction be it a Boulder field or a freeway on ramp. If she were aired down, attempting donuts in a parking lot, in 4 wheel drive, she might be approaching the kind of loads our rigs see off road all the time. We can spell out all the math if that helps. Even getting on the freeway she likely wasn’t full throttle, but for your argument let’s pretend she was and in likely 5th gear or so since the Jeep was in low range. We can even pretend she was full lock for the worst case scenario of her little mistake. 280 ftlbs in to the trans, times the 1.28 5th gear is 358.4. Times the 2.72 low range is 975. Times the 3.45 axle ratio is 3,363 ftlbs. Sounds like a lot, but in reality it is nothing. Now in the off road scenario, at the same engine rpm, in 1st gear. 280x4.7x2.72x3.45=12,349 ftlbs, but I’m sure her little mistake was much harder on the drivetrain because you said so with nothing to really solidify your case. Aside from the axle shafts, the rubicon shares the same driveshafts etc, and is more like 21,580 ftlbs at the wheel in first gear low range. 4lo still isn’t advised on the street, but from any way you look at it logically, we are much harder on them off road.

 

[word302]

You don’t actually believe that a quarter turn of the wheel on a clover leaf is the same angle as full lock off road do you? Drifters rarely break axle shafts as a tire at street pressure has far less traction period. An aired down tire, pinned between 2 rocks, is going to exert far more torque, bind, and load on the entire drivetrain than is physically possible on the street cruising around. Apply the same torque on road and the tire/ tires spin every time. As carol shelby said, there’s no such thing as too much horsepower, just not enough traction. In this discussion the opposite is true. In 8th gear on the freeway you have a .67 reduction in torque. Your 280 ftlbs becomes 187 before it gets to the tcase. Less torque in is easier on parts. The hardest you’ll ever be on your drivetrain is 1st gear, low range, full lock, axles locked, with lots of traction be it a Boulder field or a freeway on ramp. If she were aired down, attempting donuts in a parking lot, in 4 wheel drive, she might be approaching the kind of loads our rigs see off road all the time. We can spell out all the math if that helps. Even getting on the freeway she likely wasn’t full throttle, but for your argument let’s pretend she was and in likely 5th gear or so since the Jeep was in low range. We can even pretend she was full lock for the worst case scenario of her little mistake. 280 ftlbs in to the trans, times the 1.28 5th gear is 358.4. Times the 2.72 low range is 975. Times the 3.45 axle ratio is 3,363 ftlbs. Sounds like a lot, but in reality it is nothing. Now in the off road scenario, at the same engine rpm, in 1st gear. 280x4.7x2.72x3.45=12,349 ftlbs, but I’m sure her little mistake was much harder on the drivetrain because you said so with nothing to really solidify your case. Aside from the axle shafts, the rubicon shares the same driveshafts etc, and is more like 21,580 ftlbs at the wheel in first gear low range. 4lo still isn’t advised on the street, but from any way you look at it logically, we are much harder on them off road.

What’s this math crap you speak of? I’m only interested in unfounded opinions.

 

[Bruce Willys]

You don’t actually believe that a quarter turn of the wheel on a clover leaf is the same angle as full lock off road do you? Drifters rarely break axle shafts as a tire at street pressure has far less traction period. An aired down tire, pinned between 2 rocks, is going to exert far more torque, bind, and load on the entire drivetrain than is physically possible on the street cruising around. Apply the same torque on road and the tire/ tires spin every time. As carol shelby said, there’s no such thing as too much horsepower, just not enough traction. In this discussion the opposite is true. In 8th gear on the freeway you have a .67 reduction in torque. Your 280 ftlbs becomes 187 before it gets to the tcase. Less torque in is easier on parts. The hardest you’ll ever be on your drivetrain is 1st gear, low range, full lock, axles locked, with lots of traction be it a Boulder field or a freeway on ramp. If she were aired down, attempting donuts in a parking lot, in 4 wheel drive, she might be approaching the kind of loads our rigs see off road all the time. We can spell out all the math if that helps. Even getting on the freeway she likely wasn’t full throttle, but for your argument let’s pretend she was and in likely 5th gear or so since the Jeep was in low range. We can even pretend she was full lock for the worst case scenario of her little mistake. 280 ftlbs in to the trans, times the 1.28 5th gear is 358.4. Times the 2.72 low range is 975. Times the 3.45 axle ratio is 3,363 ftlbs. Sounds like a lot, but in reality it is nothing. Now in the off road scenario, at the same engine rpm, in 1st gear. 280x4.7x2.72x3.45=12,349 ftlbs, but I’m sure her little mistake was much harder on the drivetrain because you said so with nothing to really solidify your case. Aside from the axle shafts, the rubicon shares the same driveshafts etc, and is more like 21,580 ftlbs at the wheel in first gear low range. 4lo still isn’t advised on the street, but from any way you look at it logically, we are much harder on them off road.

Drifters break stuff all the time, ask me how I know. When there is bind offroad, it's overcome relatively quickly usually and powering through it when you feel it happening is not something most people would recommend. Talking about the additional torque multiplication of a Rubi 4:1 as though that makes it alright to go flying around corners at street speeds in a Sport in 4L is not a good point, it only shows that a Rubi would have sustained worse abuse given the same circumstances of improper use.

I do believe what I said earlier, driving the Jeep into tight turns at high speeds (for being in 4L) binds up the driveline in a way that is different than the common momentary binding offroad which is usually overcome fairly quickly unless doing something that would be considered abusive to the driveline regardless, not your average wheeling. The wheels have a lot of force and weight behind them when traveling at road speeds, and if bind occurs around a 30 mph tight turn common on many on-ramps, that's a lot of sustained force that drags/shocks the components while the tires are forced to equalize their speed, probably more signifcant I would think than overcoming rocks and trail obstacles at slow speeds, but maybe I'm way off base here. At least we can all agree that it's not recommended to drive in 4L on pavement.

 

[word302]

Drifters break stuff all the time, ask me how I know. When there is bind offroad, it's overcome relatively quickly usually and powering through it when you feel it happening is not something most people would recommend. Talking about the additional torque multiplication of a Rubi 4:1 as though that makes it alright to go flying around corners at street speeds in a Sport in 4L is not a good point, it only shows that a Rubi would have sustained worse abuse given the same circumstances of improper use.

I do believe what I said earlier, driving the Jeep into tight turns at high speeds (for being in 4L) binds up the driveline in a way that is different than the common momentary binding offroad which is usually overcome fairly quickly unless doing something that would be considered abusive to the driveline regardless, not your average wheeling. The wheels have a lot of force and weight behind them when traveling at road speeds, and if bind occurs around a 30 mph tight turn common on many on-ramps, that's a lot of sustained force that drags/shocks the components while the tires are forced to equalize their speed, probably more signifcant I would think than overcoming rocks and trail obstacles at slow speeds, but maybe I'm way off base here. At least we can all agree that it's not recommended to drive in 4L on pavement.

Yes, you are way off base here. The forces aren't even in the same ball park. Yes, driving in 4wd on dry pavement is a bad idea unless you're driving in a straight line, but the forces encountered off-road with the tires aired down are exponentially greater. Math don't lie. It doesn't take abuse to break parts off road, it's just the nature of the beast.

 

[Zandcwhite]

The binding and the tight turns are way blown out of proportion when talking freeway on ramps if you ask me. My beater xj with a welded dif was driven on the street for thousands of miles. The only time you'd feel and hear the tire bind and accompanying tire chirp was at near full lock turns like turning into driveways on the right. It doesn't take a physicist to understand that the differential in speed between tires on the same axle is far greater than the differential between front and rear tires. Being the jeep in question was open difs when driven in 4 lo on the street the binding was very minimal even on onramps. The front and rear tires travel a much more similar arc than the inside and outside tires of the same axle in even the tightest turns. Torque breaks axle shafts and driveshafts, and torque is low on the street driving around like normal. You can choose not to believe the math involved. You can choose to ignore the physics of just how minimal the difference in wheel speed would be on the street. You can choose to ignore the anecdotal evidence like the fact that the op's jeep is fine, the fact that we've broken multiple drive shafts and axle shafts and abused our rigs on and off road for 2 decades and not one of those breaks was on the street, the fact that the vast majority of breaks you'll find on line are people off road in low speed, high torque situations, and the fact that it's virtually impossible to find stories of people who made a similar mistake and actually caused any damage on the street. Friction on the street is easily overcome, thus burnouts and Drifting exist and yet broken axle shafts and drive shafts are far more common offroad.

 

[_olllllllo_]

Probably so they can print one owner's manual.




I built a JL/JT specific gear calculator (link to the sticky in my signature). The second tab calculates the speed in each gear.

Spoiler alert: The correct answer is in the 13th post on the first page:

That is awesome. Thanks for providing that.

 

[Vinman]

The binding is not really an issue. It just sounds and feels worse than it is. Thousands and thousands of Jeeps are in 4low in Moab for over 20 miles of trails at a time and Moab has incredible amounts of traction. And that is also on bigger than stock tires that are aired down. If you wheeled in Moab for a day or two, it may not even register to you that you are turning in 4low with gobs of traction. Same thing on the Rubicon trail.

You forgot to mention the part about getting the Jeep bouncing in the rocks where you get tires alternating between spinning free in the air then suddenly grabbing ridiculous traction when they land.
During my last trip to Moab with my TJ Unlimited Rubicon the second I was on a trail I was running 8 psi (35” KM3’s) and the rear locker was engaged until I left the trail.

 

[jeepdabest]

When divorcing her, keep the house give HER the Jeep.

 

[Beebe Senior]

I don't believe I have ever been in a situation to go over 15-20 in 4L but I know for a fact there is no way I could see my 6spd mnl getting to those speeds in 4L

 

[EbyCreek]

That's because you have a Rubicon 4:1 transfer case

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