Stock ground clearance

[WiscoProud]

this may be an odd question. The specs for a 2004 land cruiser state the stock ground clearance is 9.8 inches, however, when i measured the difference between my rear diff and the ground the number was off. I just put on 275/70r18s, which are 2.2 inches taller than stock. Adding half that to the stock clearance means my ground clearance should be 10.9 inches. But the actual measurement was roughly 9.75. This tells me that either the stock clearance isnt 9.8 inches, or that meausrement comes from somewhere other than the rear diff. Can anyone shine any light on this?

 

[sdnative]

When I had 275/70r18 they measured about 32.5". Plus there is some sag in the springs. So your measurement sounds about right.

 

[SWUtah]

When I had 275/70r18 they measured about 32.5". Plus there is some sag in the springs. So your measurement sounds about right.

275/70/18 = 33.2". Plus springs sagging should not effect the distance from the ground to the bottom of the rear diff??

 

[sdnative]

275/70/18 = 33.2". Plus springs sagging should not effect the distance from the ground to the bottom of the rear diff??

True on the springs. Those tires are 33.2 according to the math, however actual measurement varies quite a bit. My BFG AT were about 32.5"-32.7" in diameter. Plus if the tires are worn it could be a little less.

 

[WiscoProud]

The listed manufacturer spec (General Grabber At2) list them at 33.2" as well. They're brand new so wear has been taken out of the equation. All I can figure is the measurement is taken from somewhere other than the rear diff, or the 9.8" of stock ground clearance is exaggerated.

In the end it doesn't really matter, I just thought it was weird.

 

[sdnative]

That measurement is off the truck, installed on specific width wheels, specific inflation, etc. Put them on the truck and measure. You'll find they are a lot less.

 

[WiscoProud]

The problem is the tires are 2.2 inches taller than stock, yet the difference between the diff and the ground matched the stock measurement. The tires are on the truck and I can promise they are noticeably taller than stock, even if at the current air pressure they are not at the listed 33.2". I wish I had measured while the stock size was on.

 

[mcgaskins]

I always thought they measured from the middle/belly of truck for that specification not the differential.

 

[WiscoProud]

That could certainly be true and would explain the discrepancy. I always thought it would be measured from the lowest point, which is typically the rear differential on solid axle vehicles.

 

[mcgaskins]

From wiki:

"Ride height (also called ground clearance or simply clearance) is the amount of space between the base of an automobile tire and the underside of the chassis; or, more properly, to the shortest distance between a flat, level surface, and any part of a vehicle other than those parts designed to contact the ground (such as tires, tracks, skis, etc.)."

It sounds like it would be the belly of the truck since it says chassis. I'm sure there are a lot of ways to interpret it, but I'm 99% sure I've seen images from magazines or brochures where they show a diagram of the ground measured to the center of the truck like the crossmember for ground clearance.

 

[Devils Paw 80]

8.9 is stock for uzj100, not 9.8. Just squirreling around the internet and found this. I don’t own one...

 

[sammybones]

This thread makes my head hurt. And I mean that in the most positive and supportive way possible.

 

[gatormark91]

Ground clearance is to the lowest point, which is the diff. The only thing that changes it is bigger tires. Your measurement is spot on correct for your new tires.

 

[Justanothermember]

There are different types of "clearance" measurements as some of the other members here have pointed out. The most common clearance measurement is called "running" clearance, often advertised incorrectly (or covertly) by manufactures as "ground clearance" or just "clearance". I believe the manufacture spec for the LC100 quotes "running clearance" to be 9.8". while the GROUND clearance is 8.9".

Running clearance is the distance between a level ground surface and the lowest point on the vehicle excluding ALL unsprung weight. IE this would exclude the wheels, brakes, hubs, axles, and most importantly the rear diff for us 100 guys. I measured about 9.8" from the ground to the bottom of the factory side steps in the "N" height for my ACH equipped 100 on factory equipped 31" tires.

GROUND clearance on the other hand, is the distance between a level ground surface and the lowest point on the vehicle excluding wheels, brakes, and hubs. IE this measurement would measure from the rear differential (as this is the actual lowest point on the vehicle) to the ground and would be slightly less than the "running clearance" previously mentioned. As the OP mentioned, I also measured this distance to be about 8.9-9" from the ground to the bottom of the rear diff case.

Hope this helps clear things up!