First Drive: 2008 Chevrolet Suburban 2500

Much More Than Meets the Eye

G.R. WhaleJun 2, 2008
There's no badge, no change in bodywork, not even an HD decal to visually separate the Suburban 2500 from its grocery-getter brethren. Only those clued in to such things will notice the higher rear ride height, smaller-diameter wheels with eight lugs or, if they're sitting low enough, the rear end of a working pickup truck.
Unseen Upgrades
However, under the square yards of Deep Ruby metallic paint, nary a mechanical component has gone untouched. The engine drops Active Fuel Management and gets an iron block for more twist and fewer ponies than the aluminum-block 6.0-liter V-8, yet it sounds identical and pulls to the same 6000 limiter-hence, no redline on the 6000-rpm tach.
Photo 2/10
An 80-series gearbox adds two gears, raising overall first from the best half-ton's 12.5:1 to almost 15.0:1 with taller overdrive (2.87:1 to 2.50:1) at the other end and a shift toggle on the lever. Despite having fewer ponies and nearly 800 more pounds to get moving than the last 6.0-liter half-ton (with 4.10:1s) we sampled, the six-speed showed its value by getting this very-low-mile unit to 60 mph 0.3 second quicker and through the quarter in the same time but with another 3.5 mph on the dial.
The rearend is a full-floating GM 14-bolt with an overload on the leaf-spring packs and no anti-roll bar; the standard wheels are 16x6.5-inch forged alloys with LT tires. Stuff like this has kept GM pickups hauling for decades, only now with a six-speed auto and variable valve timing.
Photo 3/10
Brakes
Inside, the rear-suspension architecture changes nothing around rear seats and wheelwells, so the cabin is the same as a 1500 except that you can't get the LTZ trim spec on 3/4-tons. This 1LT, loaded with 2LT and then some, is close to the topmost 2500. It sports four leather buckets and a $100-option three-person vinyl rear bench that split-folds 50/50. For another $1000, the 3LT package would add heated front seats and mirrors and Bose audio.
Responsive analog gauges have the "pure pickup" look set into the LTZ-style single-glovebox dash, nicely melding function and design. There's a space for seemingly everything except the DVD headphones, an issue not unique to GM, and the materials are appropriate for intent and well assembled.
Photo 4/10
Sub-Mariner
We borrowed a 7400-pound boat/trailer combo for testing and while this is a ton shy of the max tow rating, it's exactly the weight you could tow if the Suburban was fully loaded. On a tri-axle trailer, tongue weight is moderate-it dropped the Sub just 0.75-inch at the hitch, and we bypassed the weight-distribution required by GM for this load in deference to the new boat trailer and lack of Reese SC or Equal-i-zer hardware compatible with surge brakes.
Since the total was 85 percent of GCWR, all towing was done in tow/haul mode and more than doubling the weight did the same for 0-to-60 times. The converter grabs around 1700 rpm but the 6.0 still feels bogged-we joked that a 3000-stall unit would help here. Once up to speed, the six-speed does a good job of choosing the right gear, and the extra midrange ratios quiet things noticeably as grades that put a four-speed at 4600 rpm were going by at closer to 3200 rpm. Tapping the brake pedal got the automatic into slowing mode, dropping gears for compression braking, and we used the thumbshifter for planning ahead on descents; almost every time we forgot we first had to shift the quadrant to "M" and then change gears with the thumb toggle.
In temperate weather of 65-75 degrees F, the water temperature indication was glued a needle above 210 regardless; the transmission digital display, which always had to be called up at restart because the park sensors were turned off, showed 180-185 degrees in steady cruising and went up to 228 F on the winding climb to 2500 feet. Consider the transmission cooling package (RPO KNP) not on our tester for warmer or more heavily loaded conditions.
Photo 5/10
The 2500 was quite comfortable dragging this load behind and felt a lot like an NHT Max Silverado. No endless bobbing and bounding, no loss of steering feel, no tail wagging, just point it and go. The 2500's steering gives up some precision and lock to the 1500's rack-and-pinion, though we never beat the pump maneuvering the 2500 as we did with the half-ton.
Go Figure (EIGHT)
We ran the figure-eight course at a constant speed for cornering, not transitions, and found the combo would round the cones in about the same speed as an average cute 'ute in the low 30-mph range (compared with the hi-po Infiniti FX50, which went through the course five to six mph faster). We surmise the tongue weight of the trailer was "pushing" the rear end, keeping the Sub better balanced than its nominal empty understeer attitude. Its tires scrubbing, the stability system kept quiet, and with the boat cleanly following the Sub, one observer noted that big 'utes handle like boats, but the boat handled better.
Most of this behavior continued on the open road, where we took freeway ramps at the same speed as mainstream traffic assuming we had the horsepower. On one particularly winding mountain road where we weren't pushing nearly as hard as around the F8 cones, the stability indicator tended to blink as the rear axle passed the apex, and while it didn't add any braking it kept us out of the throttle momentarily right when we wanted a full-throttle downshift. Using the defeat stopped such antics, and we stayed on the road just fine.
Photo 6/10
RPO Tow
By volume and dimension the Expedition EL is the closest competitor, and with Sub 2500 sales about 10 percent of the 1500 there may be no need for an EL HD. The Expedition doesn't carry or tow as much as the 3/4-ton Sub but has the third-row advantage in room and folding and is down 52 horsepower but only 18 pound-feet, which comes on earlier. A 5.7-liter Sequoia outpowers them all and has the same GCWR as the Sub 2500; the Sequoia is lighter, so it can pull a bigger trailer, but it can't carry the same crew.
Unless you're in commercial delivery, where every pound of trailer weight counts, we think the Sub 2500 makes a better family or recreational tow vehicle than a maxxed-out half-ton. Although pricier at $53,415 as is, the Sub will handle up to a 7500-pound trailer just as well, have superior range, ride smoother, and coddle the occupants-across three rows rather than two-better than any crew cab.

Comparing Base 4WD Competition
  Suburban 2500 Ford Expedition EL
Base powertrain 352-hp/383-lb-ft 6.0L OHV V-8/6A 300-hp/365-lb-ft 5.4L SOHC V-8/6A
Optional powertrain None None
Suspension, f/r Indep coil spring/solid-axle leaf spring Indep coil spring/indep coil spring
Turning circle, ft 45.3 43.9
Std tire LT245/75R16 P265/70R17
Weight, lb 6328 6080
GVWR, lb 8600 7850
Cargo cap, cu ft 45.8/90.0/137.4 42.6/85.5/130.8
3rd row head/leg/shoulder room, in 38.1/34.9/64.7 38.0/37.7/67.1
Max advertised tow cap, lb 9400 8750
Wheelbase, in 130 131
Length/width/height, in 222.4/79.1/76.8 221.3/78.8/78.3
Fuel capacity, gal 39 33.5
Photo 10/10

Comparing Base 4WD Competition
  Nissan Armada Toyota Sequoia
Base powertrain 317-hp/385-lb-ft 5.6L DOHC V-8/5A 276-hp/314-lb-ft 4.7L DOHC V-8/5A
Optional powertrain None 381-hp/401-lb ft 5.7L DOHC V-8/6A
Suspension, f/r Indep coil spring/indep coil spring Indep coil spring/indep coil spring
Turning circle, ft 40.8 39
Std tire P265/70R18 P275/65R18
Weight, lb 5661 5920
GVWR, lb 7250 7300
Cargo cap, cu ft 20.0/56.7/97.1 18.9/66.6/120.8
3rd row head/leg/shoulder room, in 35.9/32.2/63.7 38.5/35.3/65.7
Max advertised tow cap, lb 9000 10,000
Wheelbase, in 123.2 122
Length/width/height, in 207.7/79.3/78.0 205.1/79.9/74.6
Fuel capacity, gal 28 26.4
Quarter-Ton Delta
A 2500 Suburban weighs 400-800 pounds more than a similarly equipped 1500. It has a different engine, transmission, steering gear and cooler, brake booster, Z85 torsion-bar front and leaf-spring rear suspension, full-floating 10.5-inch rear axle with 3.73:1 gearset only, larger fuel tank, thicker rotors and bigger calipers, lower-output alternator, smaller wheels, and LT tires. Payload and GCWR are up about a half ton and towing by about 1500 pounds. It requires 2.5 feet more for a U-turn, a full Suburban-length extra to stop from 60, and accelerates a bit quicker. The quarter-ton upgrade adds just $1400.

2008 Chevrolet Suburban 4WD 3/4-ton LT
GENERAL
Location of final assembly Silao, Mexico
Body style 4-door, 9-pass SUV
EPA size class Full-size SUV
Drivetrain layout Front engine, 4WD
Airbags Front, front side, side curtain
POWERTRAIN
Engine type 90 V-8, iron block/alum heads
Bore x stroke, in 4.00 x 3.62
Displacement, ci/L 364/6.0
Compression ratio 9.6:1
Valve gear OHV, 2 valves/cyl
Fuel induction SFI
SAE horsepower, hp @ rpm 352 @ 5400
SAE torque, lb-ft @ rpm 383 @ 4300
Transmission type 6L80 6-speed automatic
1st 4.03:1
2nd 2.36:1
3rd 1.53:1
4th 1.15:1
5th 0.85:1
6th 0.67:1
Reverse 3.06:1
Axle ratio 3.73:1
Final drive ratio 2.50:1
Indicated rpm @ 60 mph 1700
Transfer-case model Magna MP3024
Low-range ratio 2.69:1
Crawl ratio (1st x axle gears x low range) 40.4:1
Recommended fuel Regular unleaded
DIMENSIONS/CAPACITIES
Wheelbase, in 130
Length, in 222.4
Width, in 79.1
Height, in 76.8
Track, f/r, in 68.2/67.0
Headroom, f/m/r, in 41.4/38.5/38.1
Legroom, f/m/r, in 41.3/39.5/34.9
Shoulder room, f/m/r, in 65.3/65.2/64.7
Cargo volume beh 1st/2nd/3rd row, cu ft 137.4/90.0/45.8
Ground clearance, in 7.9
Approach/departure angle, deg 16.7/20.9
Load lift height, in 34.5
Base curb weight/as tested, lb 6328/6670
Weight distribution, f/r, % 49.9/50.1
Max payload capacity/as tested, lb 2272/1930
GVWR, lb 8600
GCWR, lb 16000
Max towing capacity/as tested, lb 9400/9176
Fuel capacity, gal 39
CHASSIS
Construction Ladder frame
Suspension, f/r IFS, double A-arm, torsion bars, anti-roll bar; solid axle, leaf springs
Steering type Recirculating ball
Ratio 13.0:1-15.0:1
Turns, lock to lock 3.25
Turning circle, ft 45.3
Brakes, front/rear 13.0-in vented disc/13.5-in vented disc, ABS
Wheels 17x7.5-in alloy
Tires LT265/70R17 Bridgestone Duravis
Load/speed rating 121Q
PERFORMANCE
Acceleration, 0-60, sec (towing) 7.8 (19.0)
Quarter mile, sec @ mph 16.1 @ 88.5 (22.0 @ 64.4)
Braking, 60-0, ft 159
EPA fuel economy, city/hwy, mpg Not rated
As-tested fuel economy, mpg 6.7 tow testing
CO2 emissions est 1.40 lb/mile
PRICE
Base price $44,180
Options $9,235
Price as tested $53,415

MOST POPULAR

Truck Trend Network

TRUCK RESEARCH SNAPSHOT

Chevrolet Suburban

Fair Market Price
$46,116
Editors' Overall Rating
Basic Specifications
MSRP: $49,000
Mileage: 16 / 23
Engine: 5.3L V8
get a free quote

Subscribe Today and Save up to 83%!

Subscribe Truck Trend Magazine

Subscribe to:

Truck Trend
Magazine

PRINT DIGITAL
Subscribe Diesel Power Magazine

Subscribe to:

Diesel Power
Magazine

PRINT DIGITAL
Subscribe Truckin Magazine

Subscribe to:

Truckin
Magazine

PRINT DIGITAL
SUBSCRIBE TO A MAGAZINE
TO TOP