GM was officially first to launch a 2015 heavy duty pickup, and it doesn't suck. The redesigned 2015 GMC Sierra 2500 and 2015 Chevrolet Silverado 2500 are not without fault, but they offer a significantly better towing experience than what the rest of the segment can offer. For now.

The most interesting thing GM is bringing to the heavy duty table is advanced integration between cruise control, exhaust braking, and position sensors. Similar to hill descent control, even with a 10,000 pound load in tow down a brake-burning grade, you can leave everything but steering to the truck and it'll walk you down at the speed of your choice.

I got a chance to drive a 2500 with the gasoline Vortec 6.0, but spent the vast majority of seat time with the Duramax diesel in Silverados and Sierras. This review will focus on the oil burners.

(: The General flew me out to Arizona, give me a Silverado High Country to use on my own, put me up at a kickass golf resort in the desert, and bought me a shot of some strange tequila from a ceramic bottle just so I'd drive their new heavy duty pickups and tell you all about them.)

The GM reps spent a lot of time telling us journalists how different their customer base is between Chevrolet and GMC, and how you "know right away which truck you're looking at."

Well, yeah — if you're looking at it square in the face or someplace there's a badge. Otherwise, they're identical which is why they're being reviewed together. Think of the GMC and Chevy renditions as different trims of the same truck and don't let anybody tell you otherwise.

It's tall. Way tall. Can almost see which porno mag is on the dash of that Peterbilt in the cruising lane.This thing is perfect for people who don't want a truck but need one to tow an obscene horse trailer. Chevy knows it — they added an override feature on engine braking so horses wouldn't get scared by a blip (seriously).Somebody's got to come up with a way to have the bench front seat AND giant center console storage. A column shifter would obviously be involved, and how about the console goes straight up or down to make a seat?Given the size of this vehicle and the tires it's wearing, I think the Z71 is worthy of that "OFF-ROAD" sticker in our little dirt test.Keen to learn more about the differences between GMC and Chevy truck customers. How many of them are really convinced the trucks are significantly different?

It shouldn't surprise anyone that GM is still convinced it's hip to be square. I like the flat-fenders on their old trucks, wasn't sure it worked on their last generation, but it's grown on me again.

The big-mouthed GMC front end is handsomely imposing, and even though that Chevy face keeps reminding me of something out of "" every time I look at it, I like the overall shape of the truck.

Does anyone else think the Silverado headlights look just a little too much like eyes? We get it Chevy, you were in Transformers.

Both the GMC and Chevrolet tailgates have a nice subtle chisel to them, and I really like the way the chinks in the taillights match the fender bulges.

The most impressive thing about GM's heavy duty truck interiors is what you hear: practically nothing. Even in the diesels are way quieter than any utility vehicle shaped like a brick has a right to be. GM claims the affect is uniform in every truck from the all-business WT to the mighty Denali.

Stylistically it's squircle city up in here. Not quite round, not quite square, GM's new heavy duty dash is full of so-shaped dials layered on top of each other.

Center console storage is gar-godamn-gantuan. It swallowed a gallon jug of water and SLR cameras no problem, though it's designed to hold 8.5 x 11 files for use as a "mobile office."

The premium Denali trims on the GMC trucks have an all-digital dash, with graphical depictions of gauges you can cycle through. In my subjective opinion, none of these are as appealing as some good ol' round readouts. But if you've historically been a GM design fan, you'll be happy here.

The toggle buttons for accessories are easy to slap and nice looking. That's important because they're the third most prominent thing in the truck after the steering wheel and infotainment screen, should you choose to order it.

Overall fit and finish is fine; the brushed aluminum and stitched leather on the range toppers is awful pretty and the door handles, even on the work trucks, feel much more robust than the downward-folding playing card that opens the door on a 2014 F-250.

Besides the front bumper, the biggest differentiator between the Chevrolet and GMC trucks is the skin on the MyLink infotainment system. Functionally they're identical, but the GMC menus are slick and metal-looking while the Chev's are more colorful.

Either way, there always seemed to be a lot of screen real estate that isn't utilized for some reason.

The $500 Bose sound system option is great; you can bang the Outlaw Country XM station so loud you'll think George Strait was set up in the bed with a stack of Marshall amps plugged into the truck's in-dash inverter.

Actually that'd be more juice than the 300 watt inverter could handle but it is damn handy for charging cameras, computers, or I suspect Li-Ion tool batteries. For $300 you can order dual 150 amp alternators to keep the truck's two batteries charged.

Lane departure warning can be toggled as a "ding" sound or a vibration in the seat. So if you drive like a Bostonian, you get a proper massage (amirite?) I actually liked this feature... it's easier than you'd think to trip over a Miata when you're on the fly bridge of a pickup this size.

The Duramax 6.6 V8 Turbo Diesel pulls plenty strong with slightly better MPG as-tested in our brief torture test against a 6.7 Ford Power Stroke and and 6.7 Cummins. It's quiet in town with a satisfying rumble when you give it some throttle.

Modern diesel tech is so tidy that acceleration, noise, and smell advantages gasoline engines use to have are becoming less apparent. That said, the also-available Vortec 6.0 V8 makes a reasonably satisfying howl when you bury the throttle and it does pull a lot harder when you wanna merge like a mo'fucker. Or shorten the service life of your rear tires.

The Allison 6-speed always felt like it was in the right place at the right time, even when the truck was heavily laden. The Duramax/Allison marriage has lasted so long for a reason, you really get a lot out of the engine with this 'box.

The brakes were okay with nothing in tow, but felt too soft to me for a truck that can supposedly manage a 19,000 pound trailer. It just didn't feel "there" in panic-stopping. The exhaust brake is nice though; it does a great job managing decent speed and operates basically in silence.

Super cushy cruising on pavement, Z71 Rancho shocks are just dandy in the dirt, and the level of bodyroll in hard steering felt acceptable for a truck this heavy.

Part of me laments the loss of the old over-stuffed super-fluffy GM seats of the early 00's, but the setup here is actually more comfortable over many miles.

Nothing tricky about the beds, though I happen to quite like the shape of the integrated tie-down points. There's a dampener on the tailgate if you're too feeble to lower it down yourself.

The 'access step' halfway up the rear bumper is a lot less of an eyesore than that rickety square-stock step on the new F-150, and less likely to get caught on an off-road obstacle than Ram's folding step.

But I'll move it along... it's a heavy duty truck, and you want to know what it can tow.

GM took us out to mountain they call "Rye Grade," where they claimed they do development work on their big trucks. They had a base 2014 F-250 6.7 Power Stroke, an equally spartan Ram 6.7 Cummins and a range-topping 2015 Silverado 2500 LTZ 6.6 Duramax for us to run up and down the hill with 10,000 pounds of trailer behind each.

GM told us everything was as spec'ed out as possible for towing, though obviously the experience in the leather-soaked Silverado was more pleasant than the work rigs.

Our first test was down the hill; each truck had exhaust brakes active and cruise control set to the 55 MPH speed limit. I drove both the F-250 and the Silverado myself, and I can confirm that the Blue Oval was running away on me all the way down the hill. The Ram was a little easier to manage, but only The General's Silverado required zero pedal input whatsoever.

Chevy cleaned up on the climb too — from a rolling start at about 25 MPH, the bowtie buried both of the other two trucks over and over again.

Nick Cappa of gave us a response to that, and I'm keen to hear what you guys think too. As always, take any test set up by a manufacturer with a grain of road-clearing rock salt.

It's an exciting time to be talking about trucks— every automaker is bending the throttle on…

Since this is the first Truck Yeah! review I'll reiterate that our off-road ratings are based on the off-road context for which a truck is designed.

The Silverado 2500 is no Raptor, nor is it meant to be. It's meant to go down very rough and rutted roads at worst, which it does very comfortably.

Check out the full off-road evaluation of the for a little more detail on the truck's dirt performance.

While most of the other journalists at GM's Heavy Duty truck drive this week were busy sucking down

I did expect more aggressive rubber than Goodyear Wrangler SPA tires on the Z71 off-road package. If rutted roads are a big part of your life, you'll want to ditch those.

Big trucks ain't cheap, and that includes everything in this size segment. The upper-trim Chevy LTZ and GMC SLT diesel Crew Cabs MSRP at $61,465 and $64,200 respectively. The Duramax option alone is $7,200 and the Allison 'box is another $1,200. Warranty includes scheduled maintenance for two years or 24,000 miles, and five years or 100,000 miles on the powertrain.

But it's on-par with the rest of the market. I built a similarly-appointed 2014 F-250 King Ranch 4WD and rang up at $61,000 with diesel commanding $8,000 of that. A similar Ram Laramie Long Horn 4WD is about the same, their diesel and automatic pairing tipping the till at almost $8,500. Though it's worth noting Ram is the only heavy duty truck you have have with three pedals.

It does seem like the base prices on the GM trucks are a bit higher than the other makes, but once you start ticking boxes the playing field is pretty much level.

New GMs have proven tough to sell over the last few months, and dealers are still generally not interested in competing with other shops that are incentivizing their outgoing models.

The 2015 GMC Sierra 2500 and Silverado 2500 make it pretty damn easy to manage an massive amount of cargo, and either truck would be a nice place to spend a work day. But it was really the truck's ability to maintain speed so perfectly on substantial grades with a massive trailer that earned GM's big boys my "Truck Yeah!" nod of approval.

I imagine it'll be an easy choice for GM fans, and right now the GM trucks are the best thing going for anyone regularly towing over long distances. But if you're seriously considering an investment this big on your next truck, you'd be crazy not to wait until the 2015 renditions of competing vehicles come out later this year.

A note on the Truck Yeah! rating system:

When I get my hands on a truck for enough time to give it a legitimate shakedown, I'll break down my subjective impressions in the categories you see here. At the end, I'll stamp it with a simple overall rating that summarizes how I feel about the truck in the context it's designed for: "Truck Yeah," "Truck Eh," or "Truck Nah."

Variants

2500HD regular cab with 8' box, 2WD & 4WD2500HD double cab with 6'6" box, 2WD & 4WD2500HD double cab with 8' box, 2WD & 4WD2500HD crew cab with 6'6" box, 2WD & 4WD2500HD crew cab with 8' box, 2WD & 4WD

Powertrains

Duramax 6.6 V8 Turbo-Diesel (LML) & Allison 1000 Transmission, 3.73 axle: 397 HP @ 3000 RPM, 765 lb-ft @ 1600 RPMVortec 6.0 V8 Gas (L96/LC8) & Hyrda-Matic 6L90, 4.10 or 3.73 axel: 360 HP @ 5400 RPM, 380 lb-ft @ 4200 RPM

Curb Weight 5,909 lbs. — 7,649 lbs.

Max Payload

Gas: 9,900 lbs. Diesel: 10,000 lbs.

Max Towing

Gas, ball hitch: 13,000 lbs.Gas, fifth-wheel: 14,800 lbs.Diesel, ball hitch: 14,500 lbs.Diesel, fifth-wheel: 17,900 lbs.

Fuel Economy

Gas: Estimated 12 MPG averageDiesel: Estimated 15 MPG average

MSRP

Silverado 4WD LTZ Crew Cab Diesel: $48,230 ($61,465 as tested)

Sierra 4WD SLT Crew Cab Diesel: $48,925 ($64,200 as tested)

Images: Andrew Collins, FSI Studios, General Motors