spied 2010 GMc Sieera shows off new perforated grille

[C/K Man]

That's all I have heard so far. From what I understand, it will not be the 6.2L, it will be larger. The 6.2L has an aluminum block, and I don't think GM would use an aluminum engine in a heavy duty pickup. I suspect that it will be a version of the LS, possibly with a 'tall deck'. I think we might be hearing more before too much longer.

[nailhead425]

longer stroke as opposed to the larger bore of the 6.2. A longer stroke will take better advantage of the superior breathing of the cylinder heads, yet the 4" bore is easier to keep clean. A square bore-stroke relationship works well with this design. That's all I'm saying.

[ChevyHDGert]

Originally Posted by C/K Man

That's all I have heard so far. From what I understand, it will not be the 6.2L, it will be larger. The 6.2L has an aluminum block, and I don't think GM would use an aluminum engine in a heavy duty pickup. I suspect that it will be a version of the LS, possibly with a 'tall deck'. I think we might be hearing more before too much longer.

I read the same a few months ago when someone asked why GM doesn't put the current 6.2L in the HD's and the answer from GM was that it wasn't heavy duty enough for a HD truck.

Like I said on another forum, I hope this new motor doesn't require premium unleaded fuel to get the max. HP/Torque numbers.

[C/K Man]

Originally Posted by nailhead425

longer stroke as opposed to the larger bore of the 6.2. A longer stroke will take better advantage of the superior breathing of the cylinder heads, yet the 4" bore is easier to keep clean. A square bore-stroke relationship works well with this design. That's all I'm saying.

Right! A 4" bore is just about perfect for a light truck engine. Large enough for reasonable displacement and good sized valves, small enough for good emissions characteristics and resistance to preignition. 4" by 4" gives you just about 400 cubic inches.

[nailhead425]

It is doubtful that premium fuel would be required, but in a HD truck, even if the ECM is set for 87 octane, run 89, especially with a heavy load in summer time, and you'll get less timing pulled on the long, steep hills.

I know some complain about the High-RPM nature of the GM Gen III/IV gas engines (aka LS series) but they are designed for that. Where the Ford's are done at 4,000 rpm, GMs are designed to run all day at that RPM. It is similar to getting used to loading up a diesel vs. reving a gas engine. Once a person figures it out, they work great.

That being said, with a longer stroke the torque peak will be moved lower in the RPM band and the curve itself will flatten out. The heads are so incredible that the engines end up very peaky. Keep in mind, the L92 head flows better than big-block heads of the past.

[moman]

Wow, interesting discussion.

I do some light-duty towing with the K1500. I'm beginning to think I'm one of the few left, especially pulling up in the campgrounds with all the newer trucks. Is there a bona-fida reason (besides horsepower) that everyone pulling things gets the new trucks? The '97 will keep speed up and I really haven't felt much behind me when towing, but I max out about 5000 lbs.

[nailhead425]

If you have a 9.5 14 bolt I wouldn't trade your truck, ever. If you have the 8.5 still no really good reason to dump your rig. The 4L60E can be rebuilt and beefed when it fails, so aside from a newer 6-speed and better acceleration, I wouldn't trade either.

Payload and tounge weight are an issue. Many folks don't realize how much options, people and cargo push the curb weight. Add in a 7,500 lbs RV that puts 15% on the tounge and the truck maybe over the payload limit.

But one shouldn't overlook the HD truck "coolness" factor that many have. IMO, if you need a HD truck get one. If you don't, you're just wasting your money thinking others care.

[Michael_S]

Originally Posted by moman

Wow, interesting discussion.

I do some light-duty towing with the K1500. I'm beginning to think I'm one of the few left, especially pulling up in the campgrounds with all the newer trucks. Is there a bona-fida reason (besides horsepower) that everyone pulling things gets the new trucks? The '97 will keep speed up and I really haven't felt much behind me when towing, but I max out about 5000 lbs.

I'm a crash safety nut. A pickup is inherently pretty safe just because it's so heavy. As long as you don't roll over, you're better off than at least 80% of the other drivers on the road.

But there's still a wide gap between the crumple zones and cabin protection of your 1997 pickup and the top crash rated modern trucks (like the safety ace 2009+ F-150). I would see that as the only real reason you would ever consider replacing yours.

If anything, I think the "rugged" and "tough guy" image of a pickup truck that so many people like works far better with an old weatherbeaten truck that's still rock solid than with something brand new. And it's sure cheaper, too.

[bigboyblue]

Originally Posted by C/K Man

That's all I have heard so far. From what I understand, it will not be the 6.2L, it will be larger. The 6.2L has an aluminum block, and I don't think GM would use an aluminum engine in a heavy duty pickup. I suspect that it will be a version of the LS, possibly with a 'tall deck'. I think we might be hearing more before too much longer.

Just read it is supposed to be a V8 gas motor near 7 liters with direct injection.

http://news.pickuptrucks.com/2009/11...eavy-duty.html

[SDRacing]

Gotta love the road hugger stance!!

[ChevyHDGert]

What else might GM have up it sleeve? We hear from our sources that GM is working on a large displacement (approximately seven liters) direct-injection gas engine that would produce lots of power but with a much lower price tag than the Duramax diesel. The new DI gas engine could arrive by 2013.

So does this mean that this new 7.0L gas engine will be optional?
2013? Not sure I can wait that long.

[05ChevySilveradoSS]

Originally Posted by ChevyHDGert

So does this mean that this new 7.0L gas engine will be optional?
2013? Not sure I can wait that long.

Highly doubt it bc as you we all know the 6L is dead after this year with the 1500, and the HD's will soon follow. After being in the GM family for over 6-7 years (myself) and after my family has been in the buisness with GM for over 50 years the pattern never seems to change lol.

That engine will be the 6L's replacement, so with that being said it will be the standard engine.

[FenwickHockey65]

Originally Posted by SDRacing

Gotta love the road hugger stance!!

Did they do something to the rear fender or is that just a shadow?

[Rumblebuffin]

The new design definitely looks better. Using the half-ton-sized grille makes the front end more masculine and taller, a definite plus for me at least. Although, I would have to see that plastic hood bulge in person to make a final judgement.

Is it just me, or is the front end sitting a lot higher? Or could that be because of the trailer?

Here's the current model; this truck, and the truck in the spy photo are both 4wd (the sticker on the new Sierra is barely visible):

[FanOfDurant]

I really don't see much of a difference between the two. The black looks nicer and I like the new 3 bar grille but that's all I can see. The slightly larger tranny cooler hole will be a plus I guess. I'll have to hold off final judgement until the frame/suspension is shown in full detail. As of right now it looks like the same drop down frame set up with torsion bars... Not much new. When I heard 'New' HD truck for 2011 I was thinking an actually all NEW HD truck. This is kind of a nice MCE though I guess. I'm also wondering what they did with the standard interior?