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Discussion Starter · #1 ·
What do you think the maximum safe angles are for the FJ. I know it will vary by lift and mods. I am lifted three inches with 285s, have steel bumpers with a front winch, full skids, and sliders. I got a RAD-1 for my birthday and I need to set the angles for the rollover alarm to kick in. Any Ideas for descent, climb, and passenger/driver angles?
 

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What do you think the maximum safe angles are for the FJ. I know it will vary by lift and mods. I am lifted three inches with 285s, have steel bumpers with a front winch, full skids, and sliders. I got a RAD-1 for my birthday and I need to set the angles for the rollover alarm to kick in. Any Ideas for descent, climb, and passenger/driver angles?
To be quite honest, I don't think there is a single sane person on this forum that would even come close to committing a number as an answer. Has a lot to do with modifications, obstacle, tilt both side and forward, etc. The calculus of a roll angle almost cannot be duplicated with the same vehicle on a given obstacle, much less different vehicles on same obstacle.

Tough question sir. Sounds like your rig is well set. I'd say NEVER commit something to a set number for something as critical as this. If you're ever on an obstacle and see you aren't at your particular number yet and push it just a little further, because you still have room, you can VERY EASILY roll your FJ because of countless other factors. speed, side tilt, front tilt, back tilt, weight forward, side or back, turn angle, fluctuating speed compounded by obstacle rugosities, suspension rebound, etc.

Careful out there!

Cheers
 

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What do you think the maximum safe angles are for the FJ. I know it will vary by lift and mods. I am lifted three inches with 285s, have steel bumpers with a front winch, full skids, and sliders. I got a RAD-1 for my birthday and I need to set the angles for the rollover alarm to kick in. Any Ideas for descent, climb, and passenger/driver angles?
MY maximum safe angles have more to do with clean underwear than numbers...

That said, I'd be more than willing to lend you a protractor and video camera...
 

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Discussion Starter · #4 ·
I know it is a tough question, and I'm just looking for a very ball park figure. This inclinometer has a function where you input a maximum angle and it will start to give progressively faster beeps starting within 14 degrees of your set point. I just don't have any clue where to set the angles. I want to lean toward the side of caution..... so a very rough estimate.

Of course I'll use my better judgement when wheeling and not depend on a little alarm to decide for me. My brain is far more sophisticated and sensitive than the RAD-1 but it doesn't hurt to know when you need to start paying a little more attention. I also don't want to set the angles too low and have it beeping all the time for no reason.
 

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I know it is a tough question, and I'm just looking for a very ball park figure. This inclinometer has a function where you input a maximum angle and it will start to give progressively faster beeps starting within 14 degrees of your set point. I just don't have any clue where to set the angles. I want to lean toward the side of caution..... so a very rough estimate.

Of course I'll use my better judgement when wheeling and not depend on a little alarm to decide for me. My brain is far more sophisticated and sensitive than the RAD-1 but it doesn't hurt to know when you need to start paying a little more attention.
Heh heh. Then might I suggest the mile high (5280s) approach to angle determination?

Whence you soil thy britches, you'll know the correct angle. :rofl:
 

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The calculus of a roll angle almost cannot be duplicated with the same vehicle on a given obstacle, much less different vehicles on same obstacle.

Tough question sir. Sounds like your rig is well set. I'd say NEVER commit something to a set number for something as critical as this. If you're ever on an obstacle and see you aren't at your particular number yet and push it just a little further, because you still have room, you can VERY EASILY roll your FJ because of countless other factors. speed, side tilt, front tilt, back tilt, weight forward, side or back, turn angle, fluctuating speed compounded by obstacle rugosities, suspension rebound, etc.

breauxtus couldn't have explained it better. :bigthumb:

It's possible for one given FJ to maintain moderate lateral stability up to 35-40 degrees (or more) in an off-camber/side-slope attitude . . . . while another similarly-equipped FJ could easily go "rubber side up" at only 15-20 degrees.

One of the biggest mistakes off-roaders make, is depending upon inclinometers (and other gadgets) as an accurate reference for safe 4x4 driving. Those devices are merely conversation pieces that should never be used as a go/no-go determination for negotiating an obstacle. :worried:

In other words, there is no designated roll-over angle for the FJ, nor any other 4x4.

Like many other aspects of off-road driving, it's the driver's experience and his/her known limitations (along with that proverbial seat-of-the-pants feeling) that will prevent any mishaps on rigorous terrain. Nothing more, nothing less.
 

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Steve is right on the mark, inclometers are just gadgets that are conversation starters. The best indicator you have is your Buttclometer. The question I have always had is "Who has time to look at an inclometer if you are that close to your tip angle anyway"?
 

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This is about as far as I'm willing to take it.


River crossing two months ago. The approach. Note that soil compaction/composition has a lot to do with what you can get away with. This was a heavier grit sand and the sand had moisture in it mixed with dirt so that it was holding me. (photo by VOLHOO)


The narrow nature of the approach to the river actually held me in place while allowing me to inch forward. I'm in 4L and I'm not moving fast at all. (photo by VOLHOO)


The bumper/radiator is underwater at this point as I nose into the river bed and now I have to sort of snow-plow my way into the river using traction from all 4 tires. Note that I had traction. (photo by VOLHOO)


Coming out the other side, it wasn't nearly as steep, but it was steep all the same. (photo by VOLHOO)

So that's my limit.

Ultimate "limits" have a lot to do with (1) the geometry of your load and your center of gravity. With my aux fuel tank, I have 250 lbs of fuel onboard, BudBuilt skids, etc and have nothing on top anymore. The COG is low. (2) Never underestimate soil compactability or the nature of the soil itself. Is it rolling under you is it neutral or is it holding you in place. Rocks have different coefficients of friction based on their composition. You can get away with more on Moab sandstone than you can on hard granite.

As LANDCRUISER STEVE said - experience dictates limits. :ninja:
 

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I think bone stock the rollover rate was 43 degrees sideways 45 nose up or down, but like stated I wouldnt trust that for anything, they probably splowly lifted a surface until it rolled, with any sort of momentum you decrease those numbers by alot. I also agree with the slipping on the seat or poop factor to limit.
 

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FUNJUNKIE is going to find out what the limits are on the Grand Staircase Expedition in October.......:rocker:
 

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Wow.. You no doubt have nose down record there. That STEEP.. Ron

This is about as far as I'm willing to take it.


River crossing two months ago. The approach. Note that soil compaction/composition has a lot to do with what you can get away with. This was a heavier grit sand and the sand had moisture in it mixed with dirt so that it was holding me. (photo by VOLHOO)


The narrow nature of the approach to the river actually held me in place while allowing me to inch forward. I'm in 4L and I'm not moving fast at all. (photo by VOLHOO)


The bumper/radiator is underwater at this point as I nose into the river bed and now I have to sort of snow-plow my way into the river using traction from all 4 tires. Note that I had traction. (photo by VOLHOO)


Coming out the other side, it wasn't nearly as steep, but it was steep all the same. (photo by VOLHOO)

So that's my limit.

Ultimate "limits" have a lot to do with (1) the geometry of your load and your center of gravity. With my aux fuel tank, I have 250 lbs of fuel onboard, BudBuilt skids, etc and have nothing on top anymore. The COG is low. (2) Never underestimate soil compactability or the nature of the soil itself. Is it rolling under you is it neutral or is it holding you in place. Rocks have different coefficients of friction based on their composition. You can get away with more on Moab sandstone than you can on hard granite.

As LANDCRUISER STEVE said - experience dictates limits. :ninja:
 

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Yeah, that's some steepness happening! Cool pics uphill. How was the pucker factor there?

Again, as repeated here over and over, it's about the very specific situation to include speed, rig setup, angle, a cool head, experience, experience and if I haven't mentioned it, experience.

Uphill's demonstration here would be a study in insecurity for most folks, but he pulls it off nicely (and in a tie no less) because he knows his vehicle, he's not "rallying" and he's applying all his experience to this particular situation, as demonstrated in his description of this crawl.

Great job uphill!

This is about as far as I'm willing to take it.


River crossing two months ago. The approach. Note that soil compaction/composition has a lot to do with what you can get away with. This was a heavier grit sand and the sand had moisture in it mixed with dirt so that it was holding me. (photo by VOLHOO)


The narrow nature of the approach to the river actually held me in place while allowing me to inch forward. I'm in 4L and I'm not moving fast at all. (photo by VOLHOO)


The bumper/radiator is underwater at this point as I nose into the river bed and now I have to sort of snow-plow my way into the river using traction from all 4 tires. Note that I had traction. (photo by VOLHOO)


Coming out the other side, it wasn't nearly as steep, but it was steep all the same. (photo by VOLHOO)

So that's my limit.

Ultimate "limits" have a lot to do with (1) the geometry of your load and your center of gravity. With my aux fuel tank, I have 250 lbs of fuel onboard, BudBuilt skids, etc and have nothing on top anymore. The COG is low. (2) Never underestimate soil compactability or the nature of the soil itself. Is it rolling under you is it neutral or is it holding you in place. Rocks have different coefficients of friction based on their composition. You can get away with more on Moab sandstone than you can on hard granite.

As LANDCRUISER STEVE said - experience dictates limits. :ninja:
 
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