2015 Chevrolet Colorado: Ramp Travel Index, Take 1
March 9, 2015
Suspension articulation is one of many 4x4 attributes that have a direct bearing on off-road potential. Others include ground clearance, clearance angles (approach, departure, breakover), gearing, tires — the list goes on.
RTI is rarely found on a spec sheet, but it is something that's easily measured on our specially made 20-degree ramp.
Actually, it almost sounded like that as our Colorado's low-hanging air dam contacted the ramp before the tire even touched it.
This is a hard-plastic flap, too. It's not the sort of bendy rubber that hung below the chin of our Chevrolet Volt or Corvette. It is far larger and more rigid than the small rubbery flaps that came loose on our Silverado 1500 a couple of times.
This big honkus is designed to be stiff and unyielding in order to improve aerodynamics in the name of a higher fuel economy rating on the window sticker. It's bodywork.
I did not proceed any further because the interference only gets worse over the next couple of feet. The flap would have been torn apart, and then ripped off when I backed down. Sure, the ramp surface is a bit of a cheese-grater, but any self-respecting 4x4 truck should be able to clear this tepid 20-degree slope without touching. The texture of the thing shouldn't matter.
It was buried in there pretty good, as you can see from inside.
My first though was to unbolt the flappy bit, but as I looked closer I discovered the bolts that hold it to the bottom of the front fascia are the ones that hang down like so many stalactites. How many? Over a dozen.
But then I saw there were a couple of Torx screws pointing up into the bumper. Maybe they would help.
I removed one, but as I did I realized these merely held the lower edge of the bumper fascia in place. At this point it seemed I was going to have to remove the entire front bumper cover before I could get at the stalactite bolts from above. This did not appear to have been designed for easy removal, unlike the Jeep Grand Cherokee which a) has enough as-built approach angle to clear our ramp in the first place and b) has easily removable fasteners that allow its lower fascia to come off quickly.
As this point I retreated for a rethink. This was supposed to be a quick two-minute RTI measurement. But now it looked like I was going to have to do some major disassembly to get that flap off. And then what, leave it off?
And then I saw this on page 9-6 of the owner's manual:
Caution: Operating the vehicle for extended periods without the front fascia lower air dam installed can cause improper air flow to the engine. Reattach the front fascia air dam after off-road driving.
Yeah, right. The attachment is not designed for easy removal and replacement, and they know it. With this sentence they are trying to have their MPG cake and eat it, too.
This will have to wait for another day. Until then the Colorado gets a big fat zero. When I do eventually score it there's going to be an asterisk indicating *some disassembly required.
Maybe I should leave it at zero. It's bad enough that our Colorado Z71 4x4 doesn't possess enough approach angle clearance from the showroom floor to clear a mere 20-degree ramp. That, after all, is why I've never run a Toyota Prius or Camry up the RTI ramp, either. But the warning in the manual makes it that much worse. Anyone who runs without and comes in with a mechanical complaint risks voiding the truck's 100,000-mile powertrain warranty.
Dan Edmunds, Director of Vehicle Testing @ 6,801 miles