Comparison Test: 2007 Full-Size Domestic SUVs

Now that we've all paid more than $3.50 for fuel and seen gas pump cost readouts blur and emit steam, the reasons to buy a full-size SUV like the 2007 Ford Expedition and Chevrolet Tahoe are being whittled back down to their core strengths. For many, the time for choosing a big SUV as a fashion accessory or minivan alternative has passed, as those folks have begun migrating to less truckish and more economical crossovers.

But for those of us who want three rows of seats for the family and have a regular need to haul stuff or pull a trailer, full-size SUVs, with a frame, remain the obvious choice. And since the historical leaders in this segment, Ford and GM, have just redesigned their iconic offerings, we collected 4x4 examples of the 2007 Ford Expedition Limited and 2007 Chevrolet Tahoe LT for a friendly mano-a-mano contest. The results of our full-size domestic SUV comparison may not matter much to staunch brand loyalists, but we've decided to do it anyway. Let's meet the contestants, shall we?

In this corner...
Representing GM is the all-new 2007 Chevrolet Tahoe LT, weighing in at 5,770 as-tested pounds. This is a 4x4 SUV that knows its traditional mechanical strengths and plays to them. The chassis remains steadfastly independent up front and coil-sprung solid-axle out back. Its 5.3-liter Vortec V8 engine, while able to run either gasoline, E85 (if you can find it) or in miserly V4 mode, is nonetheless of the venerable pushrod type. Shifting is assigned to a familiar four-speed automatic featuring a handy tow-haul mode switch.

Outside, in typical Tahoe/Suburban fashion, the look is uncluttered and smooth — although some felt the rear three-quarter view a throwback, with its grid of intersecting lines reminiscent of early '90s Tahoes. The big news is the interior, which has received an extremely overdue makeover. Gone is the overwrought binnacle and button festival, replaced by a smooth and inviting dash, logically laid out and trimmed with Germanic-looking materials and textures.

A third-row seat is present, with 16.9 cubic feet of storage behind it, but still doesn't fold flat into the floor and forces adult occupants into a knees-up fetal posture. Maximum cargo volume comes in at 108.9 cubic feet, but in order to get that, two suitcase-sized third-seat modules need to be unlatched from the floor and stored in the garage.

With most of the available bells and whistles, including extravagances such as LT3 trim, navigation, rear-seat entertainment and a rearview camera, a 2007 Chevrolet Tahoe LT 4x4 setup like ours costs $50,225.

The contender
Ford's new offering, on the other hand, is a different animal. Our 2007 Ford Expedition Limited, tipping our scales at 6,073 pounds, is motivated by a 5.4-liter engine employing single-overhead cams and driving through a new six-speed automatic — albeit with an overdrive-off switch instead of tow-haul mode. Independent rear suspension supports the hindquarters.

Because independent suspension is more compact, more interior space is available, creating room for an articulated fold-flat third seat with honest-to-God leg- and headroom and 18.6 cubic feet of storage aft of it. In mere seconds, a simple button-push folds the 60/40 third seats into the floor, which, combined with the fold-flat second-row, opens up 108.3 cubes of max cargo volume.

Since our Expedition is a Limited, it's coated with handsome leather inside. When it comes to the dash, however, the soft edges cease — replaced by a mechanical-looking façade, complete with Paul Bunyan's steak knife plunged into the console for a shift lever. Think ironworker in a business suit. The tough-guy look continues outside, with prominent truck — perhaps even locomotive — styling cues.

And even though our 2007 Expedition Limited 4x4 had options such as load-leveling rear air suspension, navigation, rear-seat entertainment, 20-inch chrome wheels and the high-capacity towing option, its price fell nearly $2 grand short of the Chevy's, at $48,485.

Ding!
In addition to our normal battery of testing and evaluation, typically made up of extensive street driving and on-track performance measurements, we've added a towing test element. If full-size SUVs have a special purpose that distinguishes them from crossovers and minivans, it's towing.

At the track, the combatants posted nearly identical times, but felt very different during the trip. Ford's 5.4-liter V8, putting out 300 horses at 5,000 rpm and a whopping 365 pound-feet of torque at 3,750, pulled smooth and strong as it rumbled to 60 mph in 8.9 seconds and covered the quarter-mile at 16.5 seconds at 83.5 mph.

With more widely spaced gears and less torque from the 5.3-liter Vortec V8 — 340 lb-ft at 4,200 rpm — the Tahoe's forward progress sagged noticeably at upshifts. But 320 SAE-certified hp at 5,200 rpm made up for it, as the bow-tie special nipped the Ford to 60 by a 10th, then stumbled, but salvaged a 16.5-second tie at the line, finishing strong at 84.3 mph.

With the Ford's smoother power delivery and the Chevy's slight performance edge, call round 1 a draw. But mark these results on your scorecard, as they'll come into play again later.

Fancy footwork
Our slalom and skid pad tests were a mixed bag. Since both trucks have standard electronic stability control systems (ESC), and neither could be turned off, they messed with our usual program.

At first glance, the Tahoe's 0.70g skid pad result beats the Expedition's 0.67g, but both SUVs could have done better without electronic intervention. Slalom times were similarly afflicted, but for the record, the Ford lumbered through at 55.9 mph, while the Tahoe managed 55.8 mph. The silver lining is that if ESC hampers our limit testing to this extent, the systems ought to intervene when needed in the real world.

Besides, the real story lies on the road, where different suspension-tuning philosophies become obvious. "Tight and direct" describes the Expedition's steering, which gives the driver a degree of feedback and control that is rare in this class. Responsive 20-inch Pirelli tires doubtless have something to do with it, but the downside is that more road coarseness comes through. Independent rear suspension deals with large disturbances well, keeping the aft end well-planted at all times.

The Tahoe, on the other hand, feels like it's riding on comparatively soft and squishy tires. Sure, the level of comfort and quiet is higher, on coarse roads at least, as the 17-inch Bridgestone rubber is an effective filter. But the downside is steering that feels rubbery, too. It bounds a bit over bridge expansion joints, and the solid rear axle sometimes klomps over large bumps, accompanied by the occasional sideways twitch.

Traditionally, GM truck brakes aren't anything to write home about, but the new Tahoe's four-wheel discs feel reassuringly firm underfoot, and pedal travel is short. Panic stops of 150 feet, however, were curiously long, as a previous example we tested managed 133 feet on Goodyear Wranglers. In contrast, the Expedition's pedal feels softer and a bit less comforting in daily use, and it stopped in a ho-hum 137 feet.

Final round
Capping off our comparo, we lashed a sizable burden to the back of each ute and made them pull it up Jacumba grade, an 11.5-mile interstate hill that spends a lot of time between 5 and 7 percent.

Fleetwood Enterprises kindly allowed us the use of a 23-foot Nitrous Hyperlight 19FKX toy hauler. This enclosed box trailer, cleverly designed to hold ATVs and then serve as a sleeps-six camper after they're unloaded, has as much frontal area as SUV owners are likely to see. So in addition to weight, our heroes had to deal with beaucoup wind resistance.

Since the Expedition's optional high-capacity tow rating is 9,000 pounds and the Tahoe's standard capacity rating is 7,200 pounds, we added extra ballast to the 5,390-pound trailer when the Ford was pulling it — the idea being to burden each truck to the same percentage of its rated capacity. A full explanation is available on the tow test detail page.

In the 12-minute ascent, with 60 mph as our target speed, both made the summit within 3 seconds of each other. The power-delivery differences mentioned earlier came out here, too, as the Tahoe's fewer gears led to a mid-hill bout of gear hunting, which wasn't evident in the Ford. The Chevy's 20-hp advantage showed itself higher up at the steepest portion where both trucks were at wide-open throttle. Here the Tahoe maintained 58.3 mph, while the Expedition faded slightly to 55.8 mph. Considering trailer weight and aerodynamic drag, both are worthy performances.

The Tahoe was harder on the ears, however, with much more prominent exhaust noise. It sounds kinda cool when passing someone in daily-drive mode, but the 76.5 full-throttle decibels we measured, compared to 71.4 for the Expedition, got a bit tiring while towing up the grade, throttle mashed, for more than 6 minutes. Meanwhile, in the Ford, sipping tea, we didn't need to raise our voices to hold a conversation.

The decision is in
While the 2007 Chevrolet Tahoe LT is a nice piece, with a much appreciated dashboard makeover and stout towing performance, the lack of a stowable, adult-friendly third-row seat and a higher price caused it to trail behind its arch-nemesis when the results were tallied. And even though this is an all-new truck, important subsurface chunks of it feel outdated.

Yes, the unanimous judges' decision went to Ford's 2007 Expedition Limited, with its well-sorted steering and handling, controlled ride, very good towing performance and an adult-sized third-row seat that, importantly, folds flat into the floor. And with a sticker price low enough to let one indulge in a few more options or a down payment on a trailer and ATVs, it's hard to go wrong.

The manufacturers provided Edmunds these vehicles for the purposes of evaluation.

Second Opinions

Senior Road Test Editor Josh Jacquot says:
Let's get a few things straight. It's likely that less than half the people driving large SUVs actually need them. Most are purchased as a luxury, a gratuity justified by excuses like "I need the visibility" or " I need a vehicle big enough to haul the kids and all their stuff" or my personal favorite, "I feel safer in a big vehicle."

Here are the facts: Unless you need a vehicle that can tow 3 tons (minimum) and haul five people (minimum) and their gear at the same time, you don't need a large SUV. Trucks tow just as well if not better, and a wagon or minivan is a far more socially responsible means to move the family.

The market is bearing this fact out in ways that will hit Ford and GM right in their end-of-year balance sheets. Sales of large SUVs are plummeting from 1 million two years ago to an estimated 650,000 this year. Buyers are being reminded of their actual needs in the face of $3-per-gallon fuel costs.

Plus, these things are simply gross to drive. Just getting in means climbing up, which is as ridiculous as it is cumbersome. Once in position, rear-quarter visibility is a joke. Parking in a normal-size space is an awkward dance of wheel shuffling and neck twisting, and the road manners of these SUVs are laughable.

That said, if forced to pick between the two, I'll take the Expedition. It's the least bad.

Engineering Editor Jay Kavanagh says:
I'm dumbstruck at how many people use full-size SUVs as daily transport. Beyond all the well-known large SUV trappings of size and thirst, they simply aren't pleasant to drive. Sure, the 2007 Tahoe and Expedition are better than they've ever been, but the ever reliable laws of physics dictate that tippy, heavy trucks will never drive as well as a sedan, no matter how much sound insulation and attractive grained plastic is put in them. I'm told that people like the commanding view of the road they provide. Is the view really enough justification to live with their vices?

Only when you've got a hefty load to tow and need your vehicle to simultaneously carry the entire family do full-sizers start to make sense. Finding meaningful differences in their towing performance becomes an exercise in splitting hairs. Between the two, our towing test was a wash — the Tahoe managed its (admittedly lighter) load with less speed oscillation than the Expedition but with slightly more tail-wagging-the-dog sensation. The reality is that both the Expedition and the Tahoe excelled at towing, each pulling the grade with no drama whatsoever.

So, ironically, the decision of which one reigns supreme comes down to the execution of their daily livability. High on this list is the Ford's steering, which has much better on-center feel and response than the Chevy. This goes a long way toward making the Expedition's girth more manageable. And the Ford's power-folding third-row seat, made possible by its independent rear suspension, simply trounces the Chevy's bulky, heavy and lumpy manual third row. Despite its overstyled, gimmicky interior and the lack of a backup camera, the Ford serves daily driving duty better than the Chevy. With that said, if you're not towing, can I interest you in the view over the hood of a Mazda CX-9?

Towing performance is an important piece of the overall puzzle for full-size SUVs like the 2007 Chevrolet Tahoe and 2007 Ford Expedition. Since nothing is standardized in the towing world, manufacturers tend to diverge when it comes to how they package towing options, and how they rate their trucks.

So it comes as no surprise that even though these two brutes are direct competitors, their corporate parents' approach to towing is different, and their tow ratings don't quite match. No matter what combination of options we chose, it wasn't possible to rig them up so they had exactly the same tow rating.

Our 2007 Ford Expedition Limited came with the Heavy-Duty Trailer Tow package, which bumped our 4x4's tow rating from 6,000 to 9,000 pounds and raised the Gross Combined Weight Rating (GCWR) from 12,100 to 15,000 pounds. Cooling system upgrades and seven-pin trailer wiring and trailer brake support are the meat of this package, as the 3.73 axle ratio is common to both.

Our 2007 Chevrolet Tahoe LT lists "Trailering Equipment, Heavy Duty" as standard, but that doesn't mean it gets the highest possible tow rating. It does have the seven-pin trailer wiring already in place, but with our standard 3.73 final-drive gears, our Tahoe is limited to 7,200 pounds of trailer weight, with a 13,000-pound GCWR. Optional 4.10 gears, paired with an auxiliary transmission cooler, would have bumped each up 1,000 pounds — to 8,200 and 14,000 pounds, respectively — had they been present.

You might notice that these numbers do not match up to those in your Tahoe owner's manual. We noticed it, too. They do match the Chevrolet Web site figures, which were confirmed as the right ones by a GM contact we spoke to.

We weren't too broken up by the tow rating difference between these two, as tow rating itself isn't the end-all be-all of testing towing capability. To do it right, one needs to look at overall capacity, as reflected by the GCWR. The GCWR, simply put, is the maximum allowable weight of the entire rig and contents that you're asking the engine to move.

Payload & Towing Capacity

Payload & Towing Capacity
	Chevrolet Tahoe LT 4x4	Ford Expedition Limited 4x4
GVWR, lb.	7,300	7,700
Payload, lb.	1,776	1,825
Axle Ratio	3.73	3.73
GCWR, lb.	13,000	15,000
Maximum towing capacity, mfr., lb.	7,200	9,000
Curb weight, mfr., lb.	5,524	5,803
Curb weight, actual, lb.	5,770	6,073
Towing capacity, *actual, lb.	7,080	8,777

*actual towing capcity = GCWR - actual curb weight - 150 lb

Not only are maximum tow ratings back-calculated from GCWR, the entire engineering effort for a truck's cooling system, engine and other parts is geared around GCWR. We emphasize the word "maximum" above because manufacturers derive the tow rating they advertise based on the weight of a low-optioned truck with no one or nothing but a driver aboard. Buyers need to know that if they option up their rig and haul a lot of folks, the extra weight is eating into the remainder they can use for towing.

In order to make this comparison fair, we loaded each SUV and trailer rig to the identical percentage of their respective GCWRs. See the chart below to see how it shakes out.

Tow Test Trailer Loading

Tow Test Trailer Loading
	Chevrolet Tahoe LT 4x4	Ford Expedition Limited 4x4
GCWR, lb.	13,000	15,000
Curb weight, as-tested, lb.	5,770	6,073
Driver weight, lb.	200	200
Passenger weight, lb.	155	305
Empty trailer weight, lb.	5,390	5,390
Trailer ballast, lb.	0	1,320
GCW, as-tested, lb.	11,515	13,288
Percent of GCWR	89%	89%

Since the Ford has a higher GCWR and is rated to tow more, we loaded it accordingly. If we had used the same trailer weight for each SUV, the Ford would have been towing far less than its capability. As we loaded them, each was equally burdened to 89 percent of its own GCWR. Using this approach, the performances should be comparable.

Let the testing begin
At last the trucks are rigged and we're ready to go. Each truck towed our Fleetwood box trailer, a Nitrous Hyperlight 19FKX toy hauler, on mostly flat ground for about 200 miles as we journeyed to and from our test grade. During these runs, we had a chance to focus on general towing performance.

The lack of a load-leveling rear suspension was obvious on the Tahoe, as the rear sagged and bounded a bit while the headlights shined into other motorists' faces. We miss last year's Nivomat rear shock absorbers, a hidden passive load-leveling system that Chevrolet didn't openly emphasize, instead referring to it as a "Premium Ride" suspension. It's a pity, because last year's policy of making Nivomats standard on Tahoes with third-row seats means we would have had it here. It seems that buying the Autoride system is the only option for 2007.

Ford's rear air suspension-leveling system is purely optional, too, but our test truck had it, and it worked beautifully. It's $485 well spent. Despite an extra 1,320 pounds of ballast, mostly forward of the trailer axles and pressing down on the tongue, the Expedition's body stayed flat and rock-solid the whole way. And no one flashed their brights at us either.

We're big fans of the rear-vision camera on the Tahoe, now that we've used it to back right up to a trailer. And unlike some others that turn off once Reverse is disengaged, it stays on if you overshoot the trailer socket and have to pull forward an inch or so, turning off only when forward velocity reaches the auto door-lock speed. The negative is that a truck has to be rigged with the $2,250 navigation system to get the required display screen before you can spend another $250 for the camera itself.

Draggin' with our wagons
Once at our test area, we measured 0-60 and quarter-mile times. With a trailer, there is no wheelspin to modulate, so it's pretty much mash it and go. The results here are much more applicable to the real world than unladen drag-strip figures, because entering a freeway and merging into traffic while towing requires pretty much the same lead foot technique.

Tow Test Performance

Tow Test Performance
	Chevrolet Tahoe LT 4x4	Ford Expedition Limited 4x4
0-60-mph acceleration, towing, sec.	22.7	25.0
Quarter-mile acceleration, towing, sec.	23.1	23.6
Quarter-mile speed, towing, mph	60.7	58.5
Time to climb 11.5 mile grade, min.	11:57	12:00
Average climbing speed, mph	57.8	57.5
Climbing speed, steepest mile, mph	58.3	55.8
Towing Fuel Economy, observed, mpg	8.1	7.7

As shown above, the Tahoe does a little bit better. Our Tahoe got to 60 mph a tick of the watch before the quarter-mile was up, while the Ford didn't get to 60 mph until it had passed the finish. The Chevrolet's 20-horsepower advantage seems to be at work here.

Finally, we pulled the trailer up our 11.5-mile test grade, with the top half in the 5- to 7-percent range. Our target speed was 60 mph, and we used cruise control to avoid the temptation to get a run at the grade on the less-steep lower half. A GPS data logger measured our speed, distance and altitude throughout.

Making the grade
With only a 3-second difference in a nominal 12-minute run, the time to climb our 11.5-mile test grade was a virtual dead heat. But the devil is in the details, and a closer look shows subtly contrasting performance.

A look at the raw data shows the Chevy dithering between gears about 7 miles up, losing a bit of speed in the process. Once the grade steepens and it stays in the lower gear, it recovers and makes a strong finish, blasting through the steepest mile (miles 10-11) at an average of 58.3 mph.

The Expedition had no such gear-hunting behavior. With more torque and more cogs to choose from, it easily bridged the upshift gap and maintained speed at mile 7. But when the Ford got to the steepest bits, its 20-horsepower deficit gradually ground its speed down to 55.8 across the steepest mile, losing its midhill advantage and fading slightly to the virtual tie at the top.

Feel the noise
Other than speed and time to climb, the other noticeable difference was engine noise level. With the top 5 miles run at wide-open throttle in a struggle against gravity to maintain 60 mph, the full-throttle noise measurements we made earlier came into play.

We found ourselves nearly shouting as we tried to talk during the Tahoe ascent, while our trip in the Expedition allowed normal conversation to proceed. Looking back at our track-day full-throttle measurements, albeit on level ground with no trailer, the difference between the 76.5-decibel Chevy result, versus 71.4 in the Ford, makes sense.

Through it all, we measured fuel consumption. With the grade-climbing and flat-level road-pulling mixed together, the Tahoe gulped a bit less than the Expedition, consuming 8.1 mpg compared to the Ford’s 7.7 mpg.

Despite the differences in tow rating, grade-climbing results were a slow-motion confirmation of the unladen drag strip results. In each case, it was a tie at the finish, but differences in engine output and gearing affected how each SUV got there. In any case, both the 2007 Ford Expedition Limited and 2007 Chevrolet Tahoe LT were strong performers.

Final Rankings

Final Rankings
	Ford Expedition Limited 4x4	Chevrolet Tahoe LT 4x4
Personal Rating (5% of score)	100.0	50.0
Recommended Rating (5% of score)	100.0	50.0
Evaluation Score (30% of score)	73.8	72.1
Feature Content (20% of score)	50.0	47.2
Performance (20% of score)	93.4	97.0
Price (20% of score)	100.0	96.4
Total Score	80.8	74.8
Final Ranking	1	2
	$48,485	$50,225

Personal Rating (5%): Purely subjective. After the test, each participating editor was asked to rank the SUVs in order of preference based on which he or she would buy if money were no object.

Recommended Rating (5%): After the test, each participating editor was asked to rank the SUVs in order of preference based on which he or she thought would be best for the average consumer shopping in this segment.

31-Point Evaluation (30%): Each participating editor ranked both SUVs using a comprehensive 31-point evaluation process. The evaluation covered everything from exterior design to cupholders. Scoring was calculated on a point system, and the scores listed are averages based on all test participants' evaluations.

Feature Content (20%): Editors picked 12 features they thought would be most beneficial to a consumer shopping in this segment. Each test vehicle was then given a score based on which of those features it possessed. More points were awarded when these features were standard versus optional, and no points were given if the feature was unavailable. The score given here represents the percentage of points, out of a total possible 36 points.

Performance Testing (20%): We subjected these SUVs to our standard set of performance tests. Because towing prowess is important for many buyers in this segment, we also recorded towing performance characteristics such as: time to climb an 11.5-mile grade; average vehicle speed over the steepest portion, and; 0-60-mph acceleration with the trailer in tow. Scores were calculated by giving the best truck in each category 100 percent. The other truck was awarded points based on how close it came to the best-performing truck's score.

Price (20%): The numbers listed were the result of a simple percentage calculation based on the least expensive vehicle. Using the "as-tested" prices of the actual evaluation vehicles, the less expensive SUV received a score of 100, with the remaining vehicle receiving a lower score.

Despite prices hovering around the $50,000 mark and similar interior trim levels, there are significant differences in standard and optional equipment between our two all-new full-size SUV contenders. As it happens, the chief region where these large utes differ from smaller ones and the growing crop of crossovers is also the area where they differ most from each other: towing and hauling-related equipment.

Features

Features
	Chevrolet Tahoe LT 4x4	Ford Expedition Limited 4x4
Independent rear suspension	N/A	S
Load leveling rear suspension	O	O
Fold-flat third-row seat	N/A	O
Limited-slip differential	O	N/A
Traction control	N/A	S
6-speed transmission	N/A	S
Tow-haul transmission mode	S	N/A
Side curtain/head airbags w/rollover	O	S
E85 flex-fuel capability	S	N/A
Cylinder deactivation	S	N/A
HD tow rating	O	O
Rearview camera	O	N/A

Key:
S: Standard
O: Optional
N/A: Not Available

Independent rear suspension: The benefits for large SUVs are important. Because the rear wheels can move independently, and because unsprung mass is reduced, ride and handling can be smoother and less truckish. And because the relocation of suspension elements allows the cargo floor to be lower, there's more space in the third-row seat. The Ford Expedition takes full advantage of both of these benefits, while the Tahoe soldiers on with a traditional solid rear axle.

Load-leveling rear suspension: For those who frequently tow a trailer or carry heavy items in the back, a load-leveling rear suspension prevents sag at the rear of the vehicle, improving loaded ride and handling and keeping your headlights pointed at the road. Ford and Chevy offer such an option, but only our Expedition was so equipped. Last year, any Tahoe with a third-row seat would have included a Nivomat passive leveling system — a hidden feature referred to simply as "Premium Ride" suspension. But this year the optional Autoride system is the only offering.

Fold-flat third-row seat: When it's time to open up the cargo space, the third-row seat folds flat into the floor, thereby avoiding the inconvenience of having to remove the seats and find a place for them. The Expedition not only has this feature, but its folding action is powered. Tahoe's suitcase-style removable third-row seats are decidedly old school.

Limited-slip rear differential: With one of these, the lightly loaded inside rear wheel is inhibited from spinning on slippery or loose surfaces, increasing traction. A fully mechanical system, this is the traditional way of dealing with wheelspin. Chevrolet continues in this direction, while Ford has taken a different path and does not offer one on the Expedition.

Traction control: When imminent wheelspin is detected by the onboard computer, a combination of engine power reduction and ABS brake intervention is initiated to maintain traction. In some situations, it works better than a limited-slip, but in others it doesn't. A notable advantage is that all four wheels can be manipulated on a 4x4 vehicle such as our Expedition.

6-speed transmission: An automatic transmission with six speeds is able to provide a wider spread of gear ratios for improved low-end power and maximum economy on the highway. More gear choices also reduce the tendency toward gear hunting when climbing grades.

Tow-haul transmission mode: Towing heavy loads puts unique demands on an engine and transmission. A tow-haul switch alters the shift points to hold lower gears longer to maximize the available engine power, which helps to reduce hunting and buildup of excessive transmission heat.

Side curtain airbags with rollover protection: Occupants in all three rows are protected by airbag curtains that deploy downward from the top of the windows. They're triggered in certain side impacts and rollover events.

E85 flex-fuel capability: E85 refers to a fuel blend that is 85-percent ethanol and 15-percent gasoline. Flex-fuel means that either E85 or straight unleaded gasoline can be put into the tank. That's important, because E85 isn't readily available in most areas. GM has made a big investment in this area, putting the capability into the Tahoe and other products to help spur E85 growth. Ford's Expedition is gas only.

Cylinder deactivation: A fuel-saving strategy, cylinder deactivation pretty much does what its name implies. In periods of low demand, four of the cylinders are shut down and the engine runs as a V4. Press on the throttle, and the other half seamlessly springs back to life.

HD tow rating: Large-SUV makers, especially the domestics, usually give buyers a choice of two tow ratings. To get the higher one, an optional higher numeric axle ratio and/or upgraded radiator, transmission cooler, alternator and other parts may be offered in a package. On a 4x4 Expedition such as ours, Ford offers both tow ratings with the same rear 3.73 axle ratio — the difference being an optional "Heavy Duty Trailer Tow" package of cooling system and seven-pin trailer wiring upgrades. And even though our Tahoe 4WD LT's window sticker lists the standard feature "Trailering Equipment, Heavy Duty" and has the seven-pin wiring, it does not have the higher 4.10 axle ratio and auxiliary transmission cooler necessary to get the higher tow rating.

Rearview camera: Since it's hard to see much directly behind an SUV, the likelihood that a driver will back into something is huge. Like eyes in the back of your head, a rearview camera displays a ground-level view of what's directly behind — usually using the navigation system screen. Our Chevy Tahoe was so equipped, and it made trailer hookup extremely easy. Ford doesn't yet offer this feature on the Expedition.