Maximum incline angle before rollover danger?

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So, I was out in the mountains with the girls today and ended up going up a steeper hill than I remember ever driving up before. It was literally just the side of a mountain but there were what appeared to be old Jeep tracks. I just happened to have a little ski pole attachment inclinometer thingy which :princess: used on the center console to keep track of angles. We were going up a hill at 25-30 degrees. Seemed pretty steep.

That got me wondering. I know about the inclinometers that you can get from other brands and models. I looked at some of them just now and the old 4Runner gauges say don't go over 30 degrees. I did see one model which went to 40 degrees.

So, my question is whether or not there is a vaguely standard, known, limitation angle for going up and down hills in an 80 series. Same question for side angles too. I think we saw 20 degrees of side slope too.

i know it's complicated and a lot come into play like surface, terrain, suspension, tires, elephant on the roof, etc...

I just didn't see any reference to degrees in the posts my search revealed.

Any takers? I know I can drive up and down 30 degrees if the surface allows it.

When should I be nervous? I'm looking for numbers here.

Thanks!
 
I would go 30 on a side slop and 40 on a hill easily in a stock vehicle.

I know i've done a 25-30 side slope in a 60 series as it had an inclinometer. DOn't know how far I've pushed the 80 series but it is alot more stable then the 60.
 
Ive done 35% sideways in my fj60 and I was leaning on my door. Felt fine but not very comfortable. MIke
 
Weight transfer is a bigger contributer to rollover then angle. With that said I start to pay close attention at 30°+. As for going up an incline I don't think an 80 will ever be in danger unless alcohol is involved.:grinpimp:
 
to many variables to give a specific angle.

exactly. The center of gravity is going to be different for each vehicle. Tall lift, no lift, passengers, gear, roof racks, etc... All that affects the center of gravity. Not to mention the terrain itself.

Inclonometers are kinda useless in my opinion. Someone has a magical number stuck in there head and they focus on that little guage way to much instead of what the truck is actually doing.
 
I had mine to about 30 degrees yesterday going over some drifts on a narrow road that droped off a long ways, not very comfortable:eek: Started to slide sideways over the side quickly,would have been ugly, nailed the throttle and the rear went over the side but swung around ended up going straight up the mountain, took out the 1/4 window with a tree:bang:
I have been thinking about installing a perminant inclinometer soon, although not to rely on as there are to many variables when pushing the edge and like DiscoveryLC said I think you need to pay attention to and feel the rig
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Weight transfer is a bigger contributer to rollover then angle. With that said I start to pay close attention at 30°+. As for going up an incline I don't think an 80 will ever be in danger unless alcohol is involved.:grinpimp:

Smooth side slopes of 30°+ aren't a problem. It's hitting a bump on the high side, or a dip on the low side that can nudge a vehicle into a flop. Pucker factor is already quite high at 20° so you could always get out and look at the angles too.

Going straight up a hill? I've seen 80s at more than 45° it's the departure angle that limits you. Likewise for dropping off a ledge. Breakover angle is what hangs you up.

Now if you've got your spare on the roof, or other silly things to raise your C of g then you'd be in the red zone at lower angles.
 
to many variables to give a specific angle.
exactly. The center of gravity is going to be different for each vehicle. Tall lift, no lift, passengers, gear, roof racks, etc... All that affects the center of gravity. Not to mention the terrain itself.

Inclonometers are kinda useless in my opinion. Someone has a magical number stuck in there head and they focus on that little guage way to much instead of what the truck is actually doing.

Agreed.

Reflexes can play a big part in this, also. Despite that, if you can, try not to turn up hill when you're sidehilling. If you have to go up hill, slow down as much as possible before turning. If you feel it going over on you steer down hill if you can. If there's a drop off, you're screwed any way so you just have to take it as it comes.
 
I had an inclinometer in my FJ55. It's been a few years, but the pucker factor in the seat of the pants starts twinging around 25% whatever vehicle you're in. In my experience, I rely on how things feel, rather than the numbers on the dial, but they serve together to help evaluate just what you're getting into.

Still need an inclinometer in the 80, but experience is what really counts when driving in these situations. Take it easy at first if you don't have extensive offroad driving experience. Most will find no problem staying away from the really dangerous sidehills, just remember that discretion is required of the driver before getting in over one's head.

But sometimes things can take a sudden turn for the worse. Like in the pic above, a misplaced wheel, a rock on the uphill side or a rut on the downhill side can suddenly change the situation from safe to OMG. When you're on the edge, you want to be sure you don't get too many toes over it and lose your balance.
 
I Should have mentioned my cruiser at the time had stock tires and no lift, I was driving on concrete on the back side of a dam in the Arkansas mountains during hunting season. It was a little scary. MIke
 
Those that have a Smart Phone there are app's out there for an incline gauge. That said it is impossible to say one magic* is the golden number for all.
You have to look at so many variables.
Load weight and location. If you have a roof rack your more top heavy than one without.
Lift, the higher you go the more your chances increase rolling sooner.
Suspension, soft or firm?
Tires size, side wall rating, air pressure and tread depth.
Traction is relative to speed on the trail. Terrain, weather, tires, locked or open play big factors here.
The rig and it's maintenance.

Experience: The driver is the number one factor to the whole equation. Real life time behind the wheel, training, education of physics.... and common sense.

Asking questions like this is great because we all learn from each others experience as well.
JM2C
 
Great feedback from everyone! Of course every situation and vehicle is different. It is good to get different perspectives from people. The obvious goal is to be able to take steep trails and not roll over. What angle that is will vary by vehicle and situation.

Synthesizing the objective and the subjective aspects of steep trails is the key. That and judgment. For my part, I think having an inclinometer is valuable for building up that objective part of off-road experience. How you're "feeling" at any given time might or might not be helpful. Those numbers can be critical in certain situations and if you have wheeled your vehicle at 32 degrees before, you might be more relaxed and better handle a stressful situation if you have that number to refer to. On the flip side, I realize that you can't just assign an arbitrary number and pretend like you're safe up to that number.

Thanks for all the great input and I hope this builds more.

Some good ideas I've picked up are:

1. Considering airing down
2. Consider backing downhill before turning uphill on a steep side slope
3. Watch for bumps and dips which will increase the angles
 
2 weekends ago I went on a wheeln trip and some of the trails had some off camber stuff that was full of pucker factor
While it did not look that off camber it felt bad in the truck
And there were a few instances where I had to lean the truck against some trees and run the tree down the pass and drivers side to help with the off camber
Every truck is different depending on setup
I run a tall lift and 37's so off camber stuff is not to much fun.
 
I owned 2 different 4x4s equipped from the factory with inclinometers before I converted. And while they look cute on the dash, and make for a good conversation piece, the inclinometer didn't seem to have much practical use. Like seems to be the method of choice, on the angles I attend to the terrain and posterior muscle tension to inform my driving. I dont think I ever even glanced at the inclinometer, but I noticed everybody else in the vehicle likes to watch it. So I guess that's one thing it's good for... creating panic and hysteria among passengers.

Good question though. It would be interesting to run an experiment, figure out a way to suspend a vehicle and see what the breaking point is using one side of a flat hoist, trying various lift sizes. You know Toyota did it. Probably rolled a hundred 80s and have information filed somewhere. There would still be a lot of variability, but with that kind of data, inclinometer readings would be more applicable.

Still the information probably wouldnt do me much good, I'm one of those guys that often travels with an elephant on the roof...
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Much of it depends on what your tires are riding upon. I am alot more cautious on gravelly or loose terrain. Once you start to slide you are obviously no longer in control of the vehicle. That is something best to avoid so reduce the angle you are willing to risk in these situations.

I have almost rolled my 80 in the hill country of Texas because I started to slide in the cleachy (loose limestone gravel) that makes up much of the hill country wheeling terrain. I was lucky because my tires found solid purchase. It could just have easily gone the other way and I'd have been rolling down the side of a very steep long hill.
 
If you need to look at an inclinometer and not rely on your gut- you are not wheeling.
 
I prefer to have an "objective" reference point in addition to the "subjective" feeling of the vehicle.

Nothing wrong with that IMHO

If you need to look at an inclinometer and not rely on your gut- you are not wheeling.

...I run across comments like this from time to time on the forum and I don't really understand. Could you explain this a little more?
 

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