Chevy Avalanche Road Trip: Over the Rockies

Avalanche tunnel II
I'm just going to say this right now: Nebraska feels like the longest state in the world. I think we spent all day driving into a crosswind, finally turning off Interstate 80 to head south into Colorado, right about the time we were thinking about dinner.

Still no worries with the Chevrolet Avalanche, but we noticed that from the beginning of our trip in Washington up to this point, the Oil Life computer readout moved from 91 percent to 59 percent when we rolled into Loveland, Colo.

It's been wonderful to be able to leave all our gear in the bed of the Avalanche, safely locked up under the three-piece hardcover and locking tailgate. We have one gripe, though: We wish the bedside storage pockets were bigger. They are quite narrow and difficult to load full of anything other than small gear or clothing. We packed both cubbies with dirty laundry, several shower towels, sheets and a comforter, which probably helped insulate the other cargo in the bed.

It's worth noting that the smallish, awkwardly shaped storage area goes underneath the opening, so making use of all the space isn't easy, especially since the RamBox has changed what we think of usable storage area.

Hanna Grad II
Much of our time in Loveland — the staging area before we lunge over the Rockies — was spent shuttling to and from Fort Collins to see my niece graduate from Colorado State University. Unfortunately, we didn't make it in time to see the actual ceremony, but we were keeping in touch via text. Our "quality" time with her (graduates are such busy people) came the following morning for breakfast.

After picking up one very important passenger — the wife — we headed south to Denver to make our way over the Rockies, passing through the 11,158-foot Eisenhower tunnel (built in 1973), eventually following the Colorado River to Grand Junction, then taking a short run into Moab, Utah, for dinner. (If you ever get the chance to drive Utah State Route 128, take it. It's one of the most beautiful and varied 35-mile stretches you'll ever see.) By the end of the night we made it to Cedar City, Utah, for our last night of sleep before getting to California.

We filled up our fifth tank of gas in Green River, Utah, with the computer telling us we'd used 25.4 gallons of fuel, averaging 18.5 mpg over 471.8 miles. After filling the tank with 25.9 gallons of fuel, we calculated our fuel economy to be 18.2 mpg over the same distance. Not a bad average since we had just come over the Rockies.

During this stretch, we encountered much more uphill and downhill, and the cylinder-deactivation mode engaged more often. During all the downhill sections, the engine quickly recognized the driving conditions and kept the truck in four-cylinder mode until we touched the throttle. We could keep track of the switch between eight cylinders and four cylinders on the Instant MPG screen.

Some of the downhill sections through the Rocky Mountains were fairly steep, so the manual tap-up/tap-down thumb switch on the transmission stalk proved quite useful. The software controlling the transitions from gear to gear, modulating the engine revs, made all the shifts quite smooth. The 6L80-E transmission impressed us, especially when we needed to quickly get from 5th gear to 2nd gear or from 1st to 4th. Whenever the roads were rolling and sharp, we found ourselves more comfortable shifting manually or staying in Tow/Haul mode longer.

We liked that the gears hold longer in Tow/Haul mode, but we'd like to see more aggressive downshifting on downslopes, akin to the grade braking on heavy-duty trucks. The transmission seems plenty smart enough to get you to the highest gear as fast as possible to achieve the best fuel economy, so it seems logical that it could sense the need for quicker downshifting on grades to keep vehicle speed more under control.

We were pretty late pulling into Cedar City, but we put our 640 miles behind us. And remember, we stayed for a late breakfast in Fort Collins with our new graduate and didn't get on the road until 10:30 a.m. Thankfully, since we are continuing west tomorrow, we could sleep an extra hour in the morning because we'd get that hour back once we get into Arizona. Almost there.

Avalanche CO river II


Hows the cylinder-deactivation Mark? I never rode or drove in a truck or car with it.

@johnny doe,

Cylinder-Deactivation is GM's Active Fuel Management. I was under the impression you drive a 2011 1500. SMH!!!

From the GM website:
"AFM is also currently used on the standard 5.3-L Sierra and Yukons with the 5.3, 6.0 or 6.2-L V8 as well as Chevrolet pickups and Chevrolet and Cadillac SUVs."

Did you know this?

Yes Frank I knew that I just never test drove or rode in one with Cylinder-Deactivation before.

I don't think the 6.2 has AFM. If it does it's new for 2012.

I've drove and been in several 5.3s and I can tell when it switches from 8-4, but you really have to pay attention.

If you knew how AFM works you would never write such thing that you know when it switches from 8-4.
All 8 cylinders keep cranking, it's just that 4 of them don't receive fuel/air mixture. Both valves are closed during that cycle and compressed gas in the cylinder works as downward force.
Are you trying to tell us that you can tell/feel the injectors working? Because that's the only thing that is deactivated during 4 cylinder mode. There is nothing physical inside the engine that stops and starts working for the period of time.

@johnny doe,
I have that feature in my truck. I have a '09 Silverado 5.3. It's seemless. The truck goes into 4 cylinder mode everytime power is not needed. The AFM works only in 2WD mode. Once you stop, the truck automatically switches back to 8 cylinders so there is always full power available at take off. My truck does around 30mpg at 65mph in 4 cylinder mode. I noticed that while the truck is in cruise control it does switch to 4cyl more often and for longer periods of time. Little tap on the gas pedal forces the engine to go back to 8cyls. I like it, no complains.

@Frank - maybe he has the 4.8 since it can easily shift down and squeel the tires at 60 mph.

@Gregory J.

But what you fail to mention is how hard it is to keep in in 4cyl mode...If so much as breathe on the throttle the wrong way it will switch back to V8 mode.

Gregory J. Cool I was thinking they some how made a clutch on the crankshaft or something lol. I never really look into them though, doesn't sound like to much can go wrong. I might look at one, probably won't get a new truck till the new chevys come out.

@George, I did mention that :)

Mark, is that hardcover really strong enough to stand on? or did she put her weight on the sides of the bed and then just sit down? If it's strong enough to stand on I can definitely say i did not expect that kind of strength from a 3 fold hardcover.

although from the picture she can't weigh 120 lbs soaking wet, so maybe i should expect the cover be at least that strong.

We own a 2005 Avalanche and I was just on the hardcover
last weekend removing a decal off the window. I weigh 170#
and it held me no problem. We got ours in June of 2005 and
it now has 62,000 miles and pretty much trouble free.
It is the 4wd 1500 LT71 model and the only major repairs
were replacing the shaft in the steering, one of the front
wheel hubs and a bunch of front end rods. Wheel hub was
because of the anti brake system in it. The steering shaft from
what I was told is a known problem in their pickups too. What
really turned my Wife off from EVER buying a Chevy product
is how soon a bunch of the front end bars need replacing.
It is her truck and they needed replacement around 25k miles.
Cost about $1000 to have them done. But other than those
few problems I love the truck. Rides very, very smooth and
love the enclosed rear section. Hauled plenty of stuff safely
tucked away. I also use it to haul my motorcyle/snowmobile

@Mark Williams
Colorado 128 is in the Denver metro area, and is, quite frankly, not all that interesting. I think you were referring to Utah 128, which runs from I-70 south to US 191 just north of Moab.

@Luke in CO -- Absolutely right. Thanks for the catch. In the past, I've always flown into Grand Junction so my brain defaults to Colorado. Utah SR128.

@Gregory J. So you are telling me that you can't tell an audible difference in the engine? I can. It seems to me like there is a slight hesitation when you go from 4-8 also.

I've a simple question to You PT or any other American automotive-journalists:

what the hell are You driving quite always with all the lights turned on on a bright shiny day?
That's so stupid, proven as really unsafe, ecologically wrong (yet with added fog-lights in such a good road visibility-conditions illegal in most countries), and that aren't even DRL's (which actually GM wanted to mandate in USA long ago, yet still offer factory enabled in most of its vehicle, Avalanche too)!


Maybe he just came out of the tunnel?

Posted by: Frank | Feb 3, 2012 2:49:23 PM
@Johnny Troll,

What kind of truck do you drive?

Posted by: Frank | Feb 3, 2012 2:50:13 PM
2011 5.3L 6speed WT trim ext cab 4x4

Posted by: johnny doe | Feb 3, 2012 3:03:24 PM

With how many miles?

Posted by: Frank | Feb 3, 2012 3:31:14 PM
around 30,000 or 40,000 i think haven't looked at the odo in a while got it in novemeber i'll look if i remeber to next time i get in it

Posted by: johnny doe | Feb 3, 2012 3:44:20 PM
How many miles do you travel/work monthly?

Posted by: Frank | Feb 3, 2012 3:52:34 PM
some days 100 miles all the way up to 500 miles 7 days a week all depends on where i have to go

Posted by: johnny doe | Feb 3, 2012 4:06:46 PM

Johnny doe - so you don't know that your 5.3 WT has AFM

You say you will buy a new Chevy when the 2015's come out.


Good article: 18.5 MPG over the Rockies is great! Wondering if you have the 3:08 or the 3:42 rear end? We have a 2011 Avalanche and would really like to see a transmission gear position read out.
We can immediately detect when she goes into 4 cyl mode as there is a slight rumbling vibration, almost imperceptible.
Would have thought that the 4 cyl mode would save gas when at an extended stop, then quickly switch to 8 on take off. We did pull the black plastic car top carrier; as we never used it and it just added wind noise and wind resistance. Truck looks cleaner without it.
Avalanche is smooth riding and very quiet, hwy cruiser. We made 1100 miles in one day with its great seats. 31 gallon gas tank is sufficiently larger that the 25 found, on most pick ups. However we've never been able to put anywhere near that much in. Avalanche's 130" wheel base is shorter than the crew cabs 14-145": allowing us to pull into parking places with out having the back end cocked out of the lane. Have found that 145" wb trucks take a lot of maneuvering to straighten out when parking.

@fact checker
My truck doesn't have AFM and I do own a truck I even posted pictures of it with a lou and frank troll sign. I will buy a new chevy when 2014 chevys come out so keep trolling loser.

What engine does your truck have? other than an overactive imagination!

5.3 I didn't see AFM on the sheet.

If it is new, it has AFM.

@ BlackenMetallic:
Especially with fog-lights too? Don't You thin they can additionally blind oncoming drivers with them?

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