H3 FAQ - Vehicle Comparison

[Wisha Haddan H3]

Here are some comparisons of H3 specs with other midsize SUVs. I included the H1 and H2 just for grins

Each model is a 4x4 with options specific to its model year. I chose the most powerful engine in the most aggressive off-road package, with all towing and safety options available from the factory. So they're all factory specs (no aftermarket) gleaned from manufacturers or public sources.

Most of the specs are straight out of the books. Some are calculations for a combined result. For example, given the gear ratios and tire size, you can calculate vehicle speed at a given RPM.

Crawl Speed - estimate engine braking at 1500 RPM in 1st gear and 4-lo ... calc is less accurate for autos because of torque converter slippage.

Crawl Speed @ max HP - calculates the crawl speed using the RPM at maximum HP. Ignores benefit of torque converter.

Crawl Speed @ max torque - calculates the crawl speed using the RPM at maximum torque. Ignores benefit of torque converter. Also, does a disservice to engines with good low-end torque like the I5, compared to others with a more bell-shaped torque curve.

[Wisha Haddan H3]

The Agility category evaluates common off-road specs. There are lots of factors I can't quantify (or it's too hard to find data on) ... like body roll, shock dampening rates, spring rates, steering types and ratios, etc.

The "Max Vertical Obstacle" calculation is my own estimate based on tire height (Tire diameter - 1 inch / 2). It's really just a guess because it ignores variables like approach angles, overhangs, wheel travel, tire tread, etc. But it's still interesting to compare.

[Wisha Haddan H3]

There's more to an SUV than its off-road prowess, so here's my assessment of vehicle "utility".

The City and Highway Ranges are calculated from the EPA estimate and the total fuel capacity, minus a 2 gallon reserve.

The "Behind 1st", "2nd", and "3rd row" numbers show the cargo space with and without seats folded (or removed)

[Wisha Haddan H3]

The Track Width values were taken from manufacturer sources, so they don't all mean the same thing. Some measured from the outside tire edge and some from the tire midpoint. I didn't feel like calculating tire width from the P/LT rating and correcting them, so they are what the manufacturer says they are

[Wisha Haddan H3]

And last but not least, safety.

Any values marked n/a were untested by NHTSA.

For the Static Stability Factor, I used the NHTSA numbers when they tested a vehicle with the offroad tire option. In many cases they didn't, so I had to recalculate it using their formula, but adding the extra height from the tires. (btw, higher SSF numbers mean more stability)

Crash ratings are given for the NHTSA test vehicle, which was not always the offroad version.

d - driver side
p - passenger side
sf - front side curtain
sr - rear side curtain

f - front diff
t - fuel tank
tc - transfer case
tx - transmission

[H3slate]

Wow! You have been busy. This is all great info!

One comment, I have been in the back of an FJ, and there is no way that it has more space than the H3. My legs were pressed against the front seat, and the front seat was all the way forward. In the H3, at least I can be behind the wheel and have a 6 ft tall person sit behind me in the back.

[H3slate]

Great work on the stats Wisha!!

I was looking at an FJ today, it had the optional front skid plate on. It lowered the ground clearance in the front to under 9 inches.

It's nice to know that the H3 with standard skid plates has better ground clearance than an FJ with an optional skid plate.

[Huck BB62]

Stunning amount of work you did there!

Two comments: The speed at crawl ratio chart is good on numbers, but in reality won't really apply. You'd need a second chart separating the manuals from the automatics. The torque converter's not locked up at 1500 rpm. Granted, since the H3 in particular has jack squat for engine braking in the auto, it's a tossup, but one thing's for sure, instead of stalling, the auto will still be running, and pulling, even when the vehicle is dead stopped. Something to think about.

The H1 Alpha's mpg figures. Where's you get 'em? Dmaxes get 12mpg on the freeway pulling a 10,000lb fifth wheel! I find it really hard to believe that the H1 Alpha only gets 12mpg.

Neat work though. I LIKE it.

[Wisha Haddan H3]

Originally Posted by Huck BB62

Stunning amount of work you did there!

Two comments: The speed at crawl ratio chart is good on numbers, but in reality won't really apply. You'd need a second chart separating the manuals from the automatics. The torque converter's not locked up at 1500 rpm. Granted, since the H3 in particular has jack squat for engine braking in the auto, it's a tossup, but one thing's for sure, instead of stalling, the auto will still be running, and pulling, even when the vehicle is dead stopped. Something to think about.

The H1 Alpha's mpg figures. Where's you get 'em? Dmaxes get 12mpg on the freeway pulling a 10,000lb fifth wheel! I find it really hard to believe that the H1 Alpha only gets 12mpg.

Neat work though. I LIKE it.

Thanks!

True about the difference in crawl speeds between autos and manuals. They should be in separate charts.

About the H1 Alpha, Hummer didn't report official MPG figures on their website, so I had to do some searching. Here's one source at Autobytel. Not all sites gave mpg, but all that did agreed, so I used their numbers.