Happy in Montana
Member
No but I've driven in North Dakota and I'm not so sure I'd want to drive in 4Hi there with a part-time 4x4 system which doesn't allow differentiation between the front and rear axles as the TJ has. With a Full-time 4Hi system that comes in something like a Cherokee or Grand Cherokee? Absolutely I would in that vehicle.By your reply l can tell you've never driven in Montana.
i'd say give it a try. if parts start rolling out from under the jeep don't do that again !
even the factory LSD I put in the TJ before selling it took getting used to on really slick surfaces after spending most of this winter and all of last winter with an unlocked (open) e-locker.
I found that 4wd seemed to help starting and going but it got more squirrelly when turning. Last week I got off the highway and took surface streets for the last 4 miles of a trip back home because I was about to have a heart attack white knuckling at 50mph with all the AWD's on I-25.
The drivetrain is strong enough for that, my only concern is that it's a part-time 4x4 system which can make it more squirrely on slick surfaces. Especially during turns.
Which is why the full-time 4x4 system was developed.
how about on the front ? my '97 TJ has open rear diff. and i'm thinking of adding a powertrax lock-right to the front. would this be a sensible and stable option ?
I've lived in Montana and Idaho most my life. A lot of that time with a CJ/YJ/TJ and if you are going 55MPH and you NEED to be in 4HI.....Might as well stop into each casino you see and Gamble it up. Since you like gambling so much.By your reply l can tell you've never driven in Montana.
I Know, you have Super Jeep and you go 75mph with the cruise on over Lolo Pass in February. This is the Internet.
If the roads get icy enough there in GA to make you want to be in 4x4 I'd avoid any kind of lunchbox locker like the Lock Right. That will make your steering squirrely when you're in 4x4 on icy roads.
This is an understatement until experienced. My Current Jeep is Detroit rear, Aussie Front. I don't drive it much on the Icy roads. But the few times I have, it takes some getting used to. It can be done, but a person better SLOW down.
I knew the handling quirks and still chose my setup. But again, if I NEED to be in 4HI to travel down the streets/highway. I drive SLOW. Not accident causing slow, but as slow and cautious as I can.
Your welcome to come up to Boone and try that set up. Were getting snow and ice tonight
i wish we would get that here. i'm right at the TENN., N.C. AND GA. state lines. it's just a cold rain here.
I've shifted from 2Hi to 4Hi and back at 70+ many times, even on dry pavement.
The prerequisites are that both front and rear axles have to be going the same speed. This means minimal or no engine load, and driving in a straight line.
Realistically, driving in 4Hi on a mostly straight freeway, even on dry pavement, isn't going to hurt anything. For very gentle curves, there is more than enough natural slip in the tires to account for the slight changes in speed.
All tires have some natural slip at speed, and when you're driving in a straight line (with throttle input) in 2Hi, the rear tires are actually spinning slightly faster than the fronts. If you've ever had pulsing vibrations, you can hear the difference in speed as a beat in the pulsing vibration. Since one axle is spinning faster than the other, they continuously go in and out of phase.
But you can pause that beat by putting it in 4Hi. That locks the axles to the same speed, and whatever phase you paused it at is the constant vibration you will get. I sometimes use it to pause my vibrations at their minimum point on the freeway.
That said, on sharper turns, such as off-ramps, you risk exceeding the natural slip capacity of the tire and forcing it to either skid or slip at the road surface. This will accelerate tire wear. As you approach that friction limit, you begin to accelerate tire wear. And if you start getting noticeable chirp or wheel hop, you risk doing significant damage to the driveline.
(Note if you try this, try at your own risk.)
The prerequisites are that both front and rear axles have to be going the same speed. This means minimal or no engine load, and driving in a straight line.
Realistically, driving in 4Hi on a mostly straight freeway, even on dry pavement, isn't going to hurt anything. For very gentle curves, there is more than enough natural slip in the tires to account for the slight changes in speed.
All tires have some natural slip at speed, and when you're driving in a straight line (with throttle input) in 2Hi, the rear tires are actually spinning slightly faster than the fronts. If you've ever had pulsing vibrations, you can hear the difference in speed as a beat in the pulsing vibration. Since one axle is spinning faster than the other, they continuously go in and out of phase.
But you can pause that beat by putting it in 4Hi. That locks the axles to the same speed, and whatever phase you paused it at is the constant vibration you will get. I sometimes use it to pause my vibrations at their minimum point on the freeway.
That said, on sharper turns, such as off-ramps, you risk exceeding the natural slip capacity of the tire and forcing it to either skid or slip at the road surface. This will accelerate tire wear. As you approach that friction limit, you begin to accelerate tire wear. And if you start getting noticeable chirp or wheel hop, you risk doing significant damage to the driveline.
(Note if you try this, try at your own risk.)
Last edited:
Both are true automatic lockers. In 4x4 either/both will be an issue when on an icy surface.