How to determine "ground clearance" for a rig?

Enthusiast I

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Portland, OR, USA
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Toby
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Erkson
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I see there are roads labeled for high clearance vehicles. What is the definition of "high clearance"? What are the measuring points to determine ground clearance? Is it from the ground to the lower shock mount or to the bottom of the rear diff or simply find the lowest looking point of your vehicle and measure to the ground?
 
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ive always heard and gone with "high clearance" being a minimum of 10" from the ground to the lowest part of the vehicle. I'm sure that can and will be argued...but that's worked for me and generally what I know people to go with.
 
"true lowest structural element.". Could be the diff pumpkin on solid axle vehicles. For IFS vehicles it would be some part of the frame, maybe low eat part of exhaust. If the shock perches are the lowest point, it should be those, but those should not be the lowest part of the vehicle, but their inboard mounting does seem to get in the way fairly often
 
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Thanks for the input.
The lowest points are at the rear of my vehicle. My pumpkin is 8.5" from the ground, rear shock lower perches are 9.5". Hmm.
I'm the 3rd owner. Truck is shod with 17" rims with a 31.5" or so tire height.
 
I generally figure 1/2 the tires diameter, less 5" for the diff.
I run 35s, so 17" to the center of the axle/hub, then another 4" or so for most differentials from center to bottom. Airing down costs another inch or so.
Leaves me at 12.
 
Aah- airing down, I’m reminded of the great debate that was raging back in the 70s in the community about airing down- “ if you air down you lose clearance “ versus “ air down for better traction “ This was back when 31” tires were the gold standard, 33s were considered huge and very rare indeed. As far as High Clearance? Jeeze, I used to get my basically stock 66 VW bug just about anywhere my friend was getting his CJ. In today’s world? In my mind high clearance means no sedans, crossovers, lowrider pickup trucks, etc.
 
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onXoffroad seems to define High Clearance 4x4 Trails as "...4x4 and 6-8" of clearance or greater may be required to travel safely." Well, the "and greater" sure isn't helpful because my truck can clear 8" but not 12" and as we know, size does make a difference. That amount of ambiguity makes route planning a bit challenging.
 
onXoffroad seems to define High Clearance 4x4 Trails as "...4x4 and 6-8" of clearance or greater may be required to travel safely." Well, the "and greater" sure isn't helpful because my truck can clear 8" but not 12" and as we know, size does make a difference. That amount of ambiguity makes route planning a bit challenging.
What do you drive- I ask because in my case I have plenty of clearance, but I also have a massive 176” wheel base. If you’ve got a short wheelbase CJ on 31” tires or a LC 40 on 31s or a VW squeezing 27” tires can go a lot of places. My brother in law has a Colorado, with 31” rubber and goes a lot of places.
 
Our ride (same as in my signature):
1000019079.jpg
Front level lift. OEM "off-road" package, which is shocks and a plastic skid plate/engine protection. I replaced the plastic with an aluminum piece. Tires are LT275/65R18....they'll need replacing and I'll be on the Chevy forums regarding what the tallest tire I can get away with. We tow a trailer so I won't be going crazy, needs to be streetable.
 

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Additional info: Canadian truck & we are the 3rd owner. Previous owner used it for hunting and had a bed crane so he could dress the deer. I've been under it and have cleaned out half the Oregon river beds of sand and mud he went thru...or camped in, hard to tell :laughing:

Me? I've been wrenching on classic VWs for decades. Have a '76 Bus with a new transaxle with a Peloquin LSD...hoping to put a Subaru swap in it ($$$ :weary:). I also have a '72 Squareback and my parents were the original owners. I raced a '95 Mk.III Jetta in SCCA Solo-II, EP class, and I'm very proficient with manual tranny (heel-toe, double-clutching, & overall hooligan stuff :smilingimp:). I finally got my grail tool, a 10k Bendpak asymmetrical 2-post lift.

However, this lifted off-road life is totally NOT where I imagined I'd ever be but here I am & it's pretty fun so far! I've attended the last three Overland Expos for ideas & some minor gear.
 
Additional info: Canadian truck & we are the 3rd owner. Previous owner used it for hunting and had a bed crane so he could dress the deer. I've been under it and have cleaned out half the Oregon river beds of sand and mud he went thru...or camped in, hard to tell :laughing:

Me? I've been wrenching on classic VWs for decades. Have a '76 Bus with a new transaxle with a Peloquin LSD...hoping to put a Subaru swap in it ($$$ :weary:). I also have a '72 Squareback and my parents were the original owners. I raced a '95 Mk.III Jetta in SCCA Solo-II, EP class, and I'm very proficient with manual tranny (heel-toe, double-clutching, & overall hooligan stuff :smilingimp:). I finally got my grail tool, a 10k Bendpak asymmetrical 2-post lift.

However, this lifted off-road life is totally NOT where I imagined I'd ever be but here I am & it's pretty fun so far! I've attended the last three Overland Expos for ideas & some minor gear.
You didn’t mention speed shifting those crash boxes. I used to almost lift a front tire grabbing 2nd with my 1600 dual port. If you got your Chevy on a high clearance trail those running boards would be toast.
 
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If you got your Chevy on a high clearance trail those running boards would be toast.
Aw dang...wife uses 'em to get in-n-out :confounded: I guess I'll see clear of those paths until I can replace 'em with something else. Thanks for the tip!
 
Just to say, half the fun in going is knowing you could get stuck, or crash, and you head straight into danger to challenge yourself with whatever you drive.

The one who will define high clearance will be the guy towing you to safety and bitching about you taking your low rider over that route.

Go for it!
 
IMHO, absolute the clearance measurements are not nearly as important as knowing how to drive the terrain you’re in for the vehicle that you’re driving. Tire placement, understanding how to approach obstacles, a skilled spotter, recovery skills, and off road experience in general are a lot more important.

Your truck is high clearance in general terms, although if you’re really concerned about it, you really should take those step bars off before they get ripped off or hang you up. Replace them with actual sliders that will make a difference and you’ll be pretty much good to go as long as you know or can learn what you’re doing.
 
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