Tipping angle w/ camper?

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wicked1

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I've done some googling about this already, and it seems there is no good answer for any vehicle.. ( A slight bump could bounce the suspension and easily push the vehicle over the limits, even if you knew what the limit should be) But.. I'm sure more people than me have put a lot of thought in to this situation..

What do you think the max lean angle is for a truck w/ a FWC on top? Has anyone here tipped?

I'm not offroadng for the sake of offroading in my camper rig, but I do want to get down the sketchy roads to the unoccupied areas. I definitely went beyond my previous comfort zone on this trip, and had no issues.

I've got a little tacoma w/ fleet flatbed, and go down some small jeep roads, a full size truck couldn't get down, and a lot of these roads get pretty off camber.
And everything about the modifications of the truck raise the CG.. Flatbed is higher CG than a standard bed. The lift raises the CG. But then big wheels/tires/suspension add weight down low. And then obviously the heavy camper on top and over the cab.

I guess I'm just looking for a little general discussion about what other people are comfortable with.
Thanks!
 
It’s going to be different for different configurations. It might be better to research methods for determining vertical cg position of a vehicle. The only way I can think of to positively determine tipping angle involves a scale and some truck tilting shenanigans, which I doubt a scale facility has time or inclination to let you perform. Once you have the cg height and track width you can calculate it from there.

However, a more practical approach is to assume a cg height that you are positive is higher than the actual cg height could possibly be, and calculate the angle for that cg height. I would also suggest assuming a lateral offset of the cg of 6 inches from the centerline and calculate for the worse direction with that assumption. In addition, don’t use the outside of the tires for track width - use the center line of the tires. You’ll probably be surprised at how large the tipping angle is even with those conservative assumtions.

And in high school you thought you’d never use trigonometry!
 
Here’s an example ballpark estimate of STATIC tipping angle for my 3500hd with Grandby:

Raw data/estimates:
Bed height above ground 35 inches
Conservative estimate of truck cg 6 inches above bed floor
Truck weight 7600 lbs
Grandby cg estimated 36 inches above bed floor
Grandby weight 1800 lbs
Track width between tire centerlines 66 inches

Calculations:
Combination cg height = 35in+6in+(1800/(7600+1800))36in = 47.9 inches

Tipping angle if cg on centerline = 90 degrees - inverse tangent of (cg height / 1/2 track width) = 90 - inv tan (47.9/33) = 90 - 56 = 34.5 degrees

For tipping angle to worst side if cg is 6 inches to one side, do the same calculation but subtract 6 inches from the track half-width = 29.4 degrees

I could draw a diagram but I’m watching the KC/Bengals game right now.
 
Thanks a lot! Math isn't my strong point, so having your calcs above really helps.
Next, I need a meter in my truck to measure the angle.. As it is, I have no idea what angles I've been to. (I know, my phone will do it, and I have a digital level I could use).
 
This is a great topic. Jon R's calculations give us a conservative 30* tipping angle. I think my puckerer would be all puckered out by the time I hit 30*

I've seen some pictures/videos on this site where folks had their rigs on some crazy angles. I suppose we could compile those here and superimpose some lines on the pictures to calculate what angles they survived.
 
Again, that’s for my huge, heavy 3500hd crew cab long bed truck, with a camper that is less than a quarter of the weight of the truck, and withstock suspension and wheels/tires. Folks with raised suspensions, big tires, and a heavier camper on a half ton may get a significantly different result.

I agree Vic there’s no way I would ever sidehill that truck at 30 degrees. My display system has an inclinometer in it. Maybe I’ll keep an eye out for a good spot and see how 20 feels.
 
I have a built in tilt meter that if I get too much leaning I hear some accelerated breathing and see body reaction. It's time to pick a different line.

My gal is always willing to get out and walk and as she departs there is always the encouraging words, "If your going to die you're going to die alone" I can remember a couple times she got out and walked along with a thunderstorm/rain pounding down.

Even with the calculations there is real world surface conditions and speed factors. You maybe well under the roll over point calculations but with truck heading down hill/ side slope, just one bounce of the rear tire can bring it over. Not to mention many different surface type and conditions adds a value to your consideration.

Add some physics along with trigonometry. Every situation will have it's own safety limits.
 
Jon R said:
Again, that’s for my huge, heavy 3500hd crew cab long bed truck, with a camper that is less than a quarter of the weight of the truck, and withstock suspension and wheels/tires. Folks with raised suspensions, big tires, and a heavier camper on a half ton may get a significantly different result.

I agree Vic there’s no way I would ever sidehill that truck at 30 degrees. My display system has an inclinometer in it. Maybe I’ll keep an eye out for a good spot and see how 20 feels.
Click to expand...
My inclinometer showed 19 degrees on my half ton with a Hawk on the back once and I thought I was going to have to change my shorts after. It's super scary. As others have mentioned, it would not be so bad if you were stopped, but when moving, bouncing over rocks, etc., it's an extra layer of stress. Also, I've done it with around 8 degrees down and 14 degrees angled, again not fun. I try to stick to moderate trails at most, but sometimes they get washed out and that's where the sweating begins. Honestly, I think a couple of times I've just been lucky, not a good strategy to depend on luck. But hey, I didn't buy it to decorate the driveway.
 
Thanks Jon R for sharing some calculations. Since retiring I have not sat down and done any calculations for much. I guess when I was retiring Sage had a signature line "Work is none of my business". Been that way ever since. You're retiring soon, your going to like it!

Cheers,
 
No hard data just anecdotes: I have been 4WD driving since I was 14 years old in my dad's willey's jeep and later the 4 banger international scout. Continued driving 4WDs most of my life. I am now 68 and have never measured tilt or roll-over angle -- though I do have an education in lots of math. My advice is when on a road, listen to your gut, not your head, and not some gauge. I have never rolled, though perhaps that was a close call a couple of times. Don't get too smart or techie for your own good.
 
AWG, my issue is that I don't have experience.. or know anyone in real life who does this sort of thing. So, data is my best bet at this point. Any angle scares me the first time. Then the next, it's not bad. Driving in to camp, I thought I'd die. Driving out, no problem, on the same road. Numbers will hopefully make up for some of the lack of experience.
I do, however, get your point. I know when to turn around.. although at this point I'm probably turning around much sooner than I need to.

This situation was a wash out.. The road was washed out on one side, and that side was much lower in a few places... Places where due to the geography or large plants, I couldn't straddle the gap.
I knew I'd be fine in this situation, but didn't go as far down the road as I would have if it were in better condition... Later I watched a couple jeeps barely slow down through the same spot. (Much like the times I question my trucks ability on a road, later to watch a stock sedan get to the same place)
 
I took an off-road driving class from Tom Severin (https://www.4x4training.com/w/ ) and he had us take our F250 w/ Hallmark Guanela onto a 30 deg side slope. Didn't feel happy, but the truck was stable. He suggested never going any steeper. BTW, the class was a great experience. Really helped gain confidence to tackle rough places. Also interesting to note the F250 built-in tilt angle gauge on the dashboard was completely wrong, not even close to the protractor that Tom put on our hood.
 
wicked1 said:
AWG, my issue is that I don't have experience.. or know anyone in real life who does this sort of thing. So, data is my best bet at this point. Any angle scares me the first time. Then the next, it's not bad. Driving in to camp, I thought I'd die. Driving out, no problem, on the same road. Numbers will hopefully make up for some of the lack of experience.
I do, however, get your point. I know when to turn around.. although at this point I'm probably turning around much sooner than I need to.

This situation was a wash out.. The road was washed out on one side, and that side was much lower in a few places... Places where due to the geography or large plants, I couldn't straddle the gap.
I knew I'd be fine in this situation, but didn't go as far down the road as I would have if it were in better condition... Later I watched a couple jeeps barely slow down through the same spot. (Much like the times I question my trucks ability on a road, later to watch a stock sedan get to the same place)
Click to expand...
My suggestion is to keep doing what you are doing. It takes time to get experience. I have looked at very slightly tilting wet dirt roads that dropped off into a gully or a wash and said 'No way!', and backed out. And then I have, in dry conditions, went in on roads that were narrow single laners, that I had to stop often and reconnoiter some of the ups, downs and tilts. Going out seemed a breeze once I knew the road (for example Johns Canyon).

You may try eyeballing rigs like yours and discreetly follow them on back roads. Never hurts to watch others navigate rough tracks.

I have also had good luck jawboning other campers, and even people I see at a gas station, about local conditions.

Trust your gut. Have fun. Gain experience and confidence.
 
I'll add that yes, talking to other people on the road/trail is great. Couple trips ago, I would not have gone up a road if it weren't for the encouragement of the others who knew the road. Every time I passed someone, I asked how the road was up ahead and if they had any advice, etc. They kept me going up a scary mountain road to a beautiful lake.
And this last trip, the opposite happened.. Guy told me the road just keeps getting worse, and showed me an alternate area which would be secluded for camping, but still accessible in my rig.
I'm a pretty huge introvert, and I'd imagine a lot of people out in the wilderness are similar. But everyone I've meet out on a trail or randomly off-trail in the middle of the woods, have been the most friendly and helpful people.

(I feel like I need to qualify myself after all these questions... I'm not a complete beginner or anything. Been backpacking on sketchy trails my entire life. Rode dirt bikes and really pushed the limits on them for about 20 years of my life. But breaking my truck and stranding my family is not something I want to do!)

Thanks again, everyone!
 
Roads grades are most frequently reported as "% grade".

The top 10 steepest roads in the US are:

Ref: 10 Steepest Roads in the US [Update 2024]



  • Waipio Rd. in Honokaa, HI -- 45% gradient.
    Canton Ave. in Pittsburgh, PA -- 37% gradient.
    Eldred St. in Los Angeles, CA -- 33.30% gradient.
    28th St. in Los Angeles, CA -- 33% gradient. ...
    Baxter St. in Los Angeles, CA -- 32% gradient. ...

    Fargo St. in Los Angeles, CA -- 32% gradient.
    Maria Ave. in Spring Valley, CA -- 32% gradient.
    Dornbush St. in Pittsburgh, PA -- 31.98% gradient.
    22nd St. in San Francisco, CA -- 31.50% gradient.
    Filbert St. in San Francisco, CA -- 31.50% gradient.


  • For example: A 45% grade is about a 24 degree angle and a 30% grade is about a 17% angle.

    Slope - Degree, Gradient and Grade Calculator


    I have walked on Waipio Rd and driven down several of those San Francisco and LA Streets. For most of us when driving with our campers I think keeping the angle less than 20 degrees makes good sense. Particularly when traversing the side of a slope. Going up and down a slope presents mostly risk to stopping or climbing (brakes, traction, power). Traversing a steep slope presents a very real risk of rollover. Since center of gravity is a huge variable among different truck and camper combinations, traversing no more than a 15 degree slope might be a good conservative max angle for a pop top camper.

 
Dang...! I am gonna have to run out and buy me an inclinometer.....glue it to the windsheild...... :eek:
 
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