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Z71 Trucks should have an optional Torsen front differential or even a locking one too. I mean, unless they put forth the All Terrain HD, then that'd be okay.
A torsen diff up front could create some unwanted handling on icy roads. An electric-locking diff would be best. The PCM could unlock it if there is an ABS event, too much steering input or too much input torque, as a component saving device. Electric-lockers are much better than ABS traction control systems in off-road style terrains, but ABS based systems are general public friendly.

For 90% of the public Z71 is about status, for 9% it is the additional protection and capability. The remaining 1% is upgrading the truck with aftermarket support.
 

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As long as there is enough room to add larger tires without a lift. And by that I mean a 6" lift for 35s. The 900s look terrible with a 6" lift and 35s. My opinion, but still. The wheel opening are too small. Check out Ford and Dodge, 35s fit with shorter lifts, provided the person isn't fitting 14" wide tires on 20" rims.
 

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Doesn't sound like you are much of a GM fan. For some reason I doubt your "need" for a heavy duty off road truck, especially one who has so many GM trucks. If your needs called for what you just listed than you wouldn't be driving a IFS all weather truck as you call it. What mods have you done to your truck since your needs dictate SFA, lockers all around, alot of articulation and a winch? You must live off a logging trail or in the emptiness of Montana or something!
Many of us are GM fans, btw how many GM products do YOU own? I have 6. Blind loyalty doesn't help anyone. In fact, blind loyalty is what brings about complacency.

It isn't a stretch to understand why the GM IFS trucks are not the best for off-road situations. Although it does require some experience and understanding.

But we've had this discussion on another site, haven't we?

Go ahead and be a box checker with a ram powerwagon or better yet a Raptor because those are the manliest of vehicles for mall crawling. Enjoy your nice body and interior while everything else (the most important parts, drivetrain cough cough) are inferior to GM in terms of strength and longevity. -Tyler
Hey Tyler...so let me ask you...since AAM makes the GM and Dodge axle assemblies...how is one stronger than the other?
Well, aside from the beam-axle assembly, but let's not discuss those pesky physics things...

I really enjoy fan-boys that don't know what the heck they are talking about. AAM 1150 assemblies are in Dodge and GM products. The front axles are both AAM 925s.

I know you're not saying the Cummins is inferior in terms of longevity... If you are, you are blinded by your own ignorance.
 

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I am a GM fan, just not much of a fan of later model GM trucks although late model GM trucks make great powertrain donors for older trucks.

Quit telling me I am not a GM fan just because I am not impressed with their latest truck offerings. GM's biggest fans can also be their toughest critics!

Now back to regular schedule programming on the subject of 2014 trucks that we are all anxiously waiting to see what they are all about.
Best newbie beat-down EVER!

It is the loyal current GM customers, and the former ones that went to Dodge and Ford, who bring the greatest pressure to bear upon GM to build a better truck. Each year the lines between 1/2 tons and HDs get more pronounced. GM continues to hang onto a couple of outdated advantages that are barely anything of note and upping the ante in the towing and acceleration wars. GM doesn't have the money to do it now, but rest assured, there is plenty of ground to gain in the HD market and GM knows it!

And yes, a very nice truck!
 

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There is a lot more to it than that. Cross section of valve area is hardly a major determining factor to actual flow rates at any given rpm. Shape determines flow significantly more than size. It is true that cross section area is important, but not so much as shape. Its easy to build a 2 valve push rod to rev just as high as a 4 valve dohc.
Exactly. And head-flow must be matched to application and engine. Put some big Rect Ports on a 366 school bus block and not only with the bore shroud the valves, the engine simply won't move enough air at low-rpm to keep the port velocity high enough to make it responsive. Ford 2V, 3V, and 4V mod motors are another EXCELLENT example of head flow vs. out put and how bore size significantly changes the performance.
 

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Which off-road community are you referring to? I've taken my 1996 Z71 off-roading in Colorado several times and had no problems. Most people in the off-road community use Jeeps. You're searching for excuses - lame excuses.
Oh yeah, which trails? I run up in Colorado a couple times a year. Most of the trails (note I said most) can be run with a stock IFS GMT400 with 285/75R16s and a good rear diff (good, not Gov-Loc). I've given water to Mtn Bikers up there. Makes me feel like a tool running in 4-hi. Most of the regular trails up there are pretty tame, but a F350 or a GM2500 crew-cab long bed is going to long day on the most mild trails. SFA or not, on switch backs, long wheel base stinks.

I prefer China over union made on many things.
Dangerous thinking. First, Union jobs are still jobs. Secondly, those Union pensions would be honored by the Gov't, which means you, me and every other tax payer. Finally, the best example of this is Milwaukee tools. Their quality took a noticeable and significant impact when their production was moved to China. Might as well go buy a Dewalt. Union or not, they used to make great tools, now they make good ones. I was a UAW worker in 1994 on the line, so I've seen both sides.

IFS on HD is not crap. What's wrong with it? Be specific.
With the GMT-400/800 IFS? EVERYTHING. bump steer, weak tie-rods, banjo diff housing, low-strength components, deflection, etc. It is TERRIBLE by comparison. I'd take an 8-lug, 30 spline 8.5 10bolt over the first gen IFS any day.
I wouldn't say the 900-HD IFS is crap, but it isn't golden gem of awesomeness either.
First, linear-rate torsion bars are more than enough reason. To get a 6k GVWR front axle capacity, the torsion bar rate was increased significantly. Because they are linear and not progressive like Dodge and Ford, the suspension is stiffer. Fine when you're hauling around a plow, but a bit much empty. Secondly, while the individual suspension travel is similar to Ford and Dodge, what the SFA crowd has to benefit is the lever effect of the beam axle. With similar spring rates, this benefits the SFA in terms of articulation, the IFS in terms of ride.
However, where as the IFS may have a design advantage in terms of ride, it suffers by comparison because each tire is independent, there is no effective lever across BOTH springs and thus a higher spring is required.
But most importantly, and this is often where the PRO-IFS and ANTI-IFS crowd but heads, the GM IFS has too many negatives in terms of off-road. Tire size capacity is too small, strength of the axle housing, half-shaft strength and steering component strength are all too light for large tires, on a heavy truck in a moderate to heavy off-road situation.
That's not to say that IFS in general is terrible off-road. That is not true, it is just more expensive and difficult to build.
The GM 1/2ton coil spring suspension is a better design for off-road, but they still need to facilitate larger (heavier) wheel and tire combinations.

It isn't a question of IF IFS can be good off-road, it is the truth that the GM IFS ISN'T that so many cannot accept.

Well good for you - REAL truck folk. What a joke. I won't be hurt if GM loses you as a customer.
Each GM customer is important. Let's take the Jeep example: The Grand Cherokee is IFS/IRS but the Wrangler Unlimited is SFA/SRA. Both have impressive sales numbers, for entirely different reasons.
The idea that GM can afford to lose a customer is foolish. It is easier to keep a customer than win over a new-one.

Ground clearance at the frame (and especially the differentials) is the important stat. And the only reason frame clearance is important is for cross-over angles, not field ruts. Rut depth is completely dependant upon tire size. So you really appear to not know what you're talking about.
The lowest part on ANY HD GM truck is the bottom of the 14 bolt full-float. The issue with IFS is the wide, low hanging front cross-member. While it isn't lower than a super Dana 60, the width of a front pumpkin is pretty narrow and near one tire, thus pretty easy to avoid stuff. FYI, I've wheeled with a DANA 60 SFA and 30.5" tires and didn't hit a single rock on the diff cover.

You cannot point to HD IFS and frame cosmetics alone as to why GM lags Ford. Most of your complaints are typical wanna-be machoisms that most people don't care about.
Look, sales number don't lie. Ford has been beating GM in HD sales with lousy gas engines, a problematic diesel since 2003, lower fuel economy and 2nd place performance. Perception is an amazing sales tool.

If, and this is a BIG IF, GM were to revamp the IFS to a coil-over system, that supported a much larger tire (Safely) with wider fender/quarter openings, a better rear locker, a front torsen/locking diff, stronger front half-shafts, much stronger steering components, and a longer travel suspension with sway-bar disconnect, the GM IFS could easily hang with the Raptor.
 

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So what makes (one) a "real truck man"?
Part fan-boy, part critical old fart that doesn't like to spend money just because something is new, and a level of (extreme) thriftiness that demands long lasting stuff.

We can all agree that a Honda lover who buys a Ridgeline to haul a heavy trailer and run off-road is a blind fan-boy. Yet when someone says that the beloved GM isn't top of the pack in one area, well they are the devil's spawn here to molest your dog and kick your daughter.

Criticism, when accurate and direct, doesn't diminish every positive attribute. However, a failure to accept and learn from said criticism is a critical and past mistake common within GM.
 

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That's your opinion. FACTS show that GM truck frames last just as long as Ford and Dodge. Doesn't GM have the "the longest lasting, most dependable trucks on the road"?
You...uh...aware that they include the 1981-1987 trucks in that mix?

Sure, GM doesn't have an answer to the Raptor and Power Wagon, but HD truck to HD truck, GM holds their own. And, oh by the way, your claim that SFA is better than IFS for off-road is laughable when you also point to the Raptor as an example of GM falling behind Ford. The Raptor is probably the most successful off-road truck and it has IFS. Again, you're wrong.
The Raptor IFS is completely different. Long arms, coil spring, HD half-shafts, HD diff housings, HD shocks.
Which "off-road" do you mean? The Raptor is much better for high-speed, sand dune runs, but in rocks it suffers by comparison.
The GM HD Torsion bar IFS is a joke by comparison.
You are pointing to a better designed product and suggesting that just because the Raptor is IFS means that GMs version of IFS in the HD trucks isn't sub-par by comparison to other HD trucks. This is little-kid logic. Other than the IFS, that's all they have in common.
How about this...the Raptor and the H2 are both IFS and share the same tire size, yet where the H2 was notorious for bending tie-rods in off-road use, the Raptor is not.

my 2002 GMC 2500 HD duramax/allison has over 220,000 miles on it. pulling boats, 30+ foot travel trailers, significant off road hunting in the CO mountains and I have had ZERO issues with the frame, in fact the overall exterior of the truck is in fantastic shape. The only rust was on my aftermarket nerf bars that I just took off this summer
But you're obviously not a "REAL" truck guy, and Colorado doesn't have a "REAL" off-road community, and your truck hasn't been exposed to "REAL" winters like the "REAL" truck guys where FOD is from. So your experience doesn't count. LOL.
I've wheeled pretty much every trail in Colorado, Utah, New Mexico, Wyoming and Arizona. I even ran a full-size SFA truck to the power house at Bridal Veil falls. If you were running nerf bars, you weren't wheeling where I (and many others) consider off-road.
Running IFS in CO isn't a big deal, I've run many of the trails there in a GMT400 with 285s. I bet you guys think you're wheelin' until you see the hippies from Rico show up in their Subbie. Heck, I recently ran Engineer pass and stopped to take some pictures and talk to a couple mountain bikers.

Unless you know the Watson's from Carbondale, you're probably not running the really hard trails with your IFS.
...and if you DO know the Watson's, you're not running IFS.
 

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This is about GM trucks. An open forum for the discussion of them, their attributes, their positives and negatives.
Opinions are often regarded as facts and facts often discounted when they do not conform to our opinions.

And you other guys need to quit arguing over off road crap. It's all your own opinion. Rock crawling doesn't = the best off road. Neither does mud, sand, snow, or dirt individually. The best vehicle for off road is one that can handle all or most of everything. One that if SHTF, it will get you to safety. In that regard ALL 4x4 trucks are more than capable. However, You certainly don't want a SFA running a high speed desert escape or plowing through sand dunes, or trails. Way too harsh. Which is why in "MY" own opinion half ton trucks are better for off road. And guess what, they all have IFS.
Off road may not be important to you, but it is to many. The mere suggestion that it isn't, overlooks the marketing mystique associated with the toughest looking truck.

Secondly, you are correct, and incorrect in the same statement about what is best.
While I agree, the best truck is the one that will get you where you need to go (and back) when you need it. I must state that the truly best truck will do it over and over again. Simplicity and durability are very important to HD truck buyers.

Running dunes and high speed desert blasts aren't really the key sports associated with HD truck buyers. Heavy 3/4 and 1 tons with narrow, short tires and tons of torque are quickly buried in the dunes, in high-speed runs the stiff rear suspension is punishing and the shocks are quickly over-heated and suffer reduced effectiveness. There is just too much weight to be ideal, no matter what suspension is under the front rails.

Running trails is closer and towing/HD work is at the top of what HD truck buyers demand. There is nothing "harsh" about running a trail with a SFA vs. IFS. Unless you confuse graded Forest Roads as trails, then by all means continue, because single-speed transfer case IFS/IRS SUVs are just fine on them, because most trails are run at a slower speed. Many on here that live back east, or never venture off the beaten track, don't realize how many guys actually will take their new HDs off road, into areas most people don't travel, several times per year. Out here, trucks have to work and most guys can't afford an off-road only machine. Out here it is called Arizona pinstripes and it is from the manzanita and other bushes that scrape the clear coat. The key is, you gotta go off road here to get to the good areas. Too many people road hunt, or stay on the graded stuff, so going deep is critical. And forget the Rangers, Razors, or quads, there are more regulations on them, than using your truck to pick up downed game. More over, in many areas of Arizona the land can be passable, but in the wet season (late summer or winter) trails can become deep in mud, exposed rocks, ruts, downed trees, or worse covered in deep snow at night, where the base melts throughout the day, then freezes, so the muddy, rutted trails freeze hard, with a layer of ice. It is just part of the game.

Also, I agree that 1/2 tons are better than HDs for most off-road situations because they are generally shorter and lighter.
A crew-cab, long-bed Super Duty is horrible on most trails. Not that long ago, there were some pretty great trail-running SFA and near SFA 1/2 tons produced by O.E.

But the other thing to keep in mind is that this isn't an IFS vs. SFA argument.
This is a GM IFS vs. the competition argument.
GM isn't ever going back to SFA. This has been made clear numerous times. And to be honest, they don't have the money to do so.
But what they DO have the money to do is revamp the GMT900HD IFS into a more modern, competitive more durable and capable IFS.
You all need to put down the fan-boy status and recognize that as good as the GM HD front suspension is, it isn't anywhere near good enough. It needs to be at least a coil-spring, longer travel IFS with larger diameter half-shafts, more durable CV-joints and steering components. The GM IFS ought to be able to support factory installed larger and heavier tires. The Raptor has 35s, so should the GM. In both the HDs and the half-tons. Same with a torsen diff up front, selectable rear locker (not the Gov-Loc, one of Eaton's torsen E-lockers).

There is no reason why GM can't build a Raptor fighter or a Power Wagon fighter with IFS..

All that tells me is that you and natzeRancher have is a lot money to throw away and a bunch junk trucks in front and back yard.:rolleyes:
Hardly. Did you read what I wrote about wheeling with a GMT400?
Here's the thing, I've had a few trucks, most have tons of mileage on them and I fix them when stuff breaks.
So I have a great idea of what works and what doesn't.

As far as the Tundra is concerned no REAL TRUCK GUY would ever buy a cheap Japanese piece of junk with rice paper thin bed sides, and transmissions made from recycled fortune cookies. No REAL TRUCK GUY would put up with a tail gate that will bend if you even think in your mind that you will set something on it, and frames that rust at the mere mention of water in the midst of an arid desert.
Just like in the 80s...they will be back, over and over again, until they get it right.
 

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Understand guys, there will NOT be a SFA GM HD Truck. Not this time, not next time. They are NOT going to do it.
GM has officially stated that a) they will not be going back to a SFA and b) will not be adding a manual transmission.

This is NOT a SFA vs. IFS debate. Even though many want it to be. Any redesigns have been done and based on their conclusions with the 900HDs, the short comings that we in the field may see, are not high on their list of priorities.

WRT to the old solid axle. My Dad has the last year of the vaunted 'semi' Dodge of 94-2001 with the solid axle and it wanders on the highway something terrible. Yes the SFA is easier to lift but have you looked at a GM 3/4 ton lately? They are already jacked up pretty high.

One last thing on the awesomness of Dodge - have you ever noticed the way tires on the Dodge stick out ever so slightly beyond the fenders? You know what neat trick this does? It covers the sides with dirty road spray whenever it rains. That's the whole problem with building your products based on what 17 year old boys think is toooootally cool.
The Dodge "wander" is due to a worn track bar, not a faulty design. Same as the ball-joint issues with Ford, worn parts from a lousy supplier.

The GMT-900HDs sit high, but they don't allow large tires at stock height. So to get larger tires, they require a lift. Part of this is due to component strength and warranty concerns.

17 year old think tires that stick out the sides of pickups are cool? Last time I checked, it was video games, girls, quick little lowered cars, stereo systems, girls, motorcycles, girls and young women. Most 17 y/o boys can't afford new trucks. Heck, most 27y/o can't.

I find it quite interesting that all of the self proclaimed truck experts do not realize that Dodge offers everything that they find as a flaw on the GMT900 HD's yet they still trail GM in the HD market. Do many of you think that the desires of those in your microcosm always reflects those of the macrocosm? Yes GM's IFS is compromised in many ways, and in some ways purposefully to give buyers a ride/ handling balance that leans more towards comfort on the road than off road prowress. Do you honestly think that ALL HD buyers purchase their vehicles only for their trail running/ offroad prowress or is it to perhaps tow something on the road occasionally?
Well, with that logic...
Ford dominates the HD truck market and GM dominates the light duty market.
Ford and Dodge increase their representation in the HD market over that in the LD market.
So, it would stand to reason that exterior and interior looks, features, content and performance are NOT factors in the GM HD market, would you agree? If those were the main selling points, GM should dominate the HD market like they do the LD market.
Dodge has never sold in huge numbers, but they are doing better than Toyota and Nissan.
Their HD trucks have a cult following. Albeit a LARGE cult.

The problem is that the GM IFS is NOT appreciably better than Ford in ride and drive. It used to be, but it isn't any more.
Ford dominates the HD market and Ford and Dodge have over 70% of the HD market because of owner loyalty and customer perception.

GM can do better.

This absolutely jaded thought that GM HD's are absolutely deplorable , and that Ford HD's are nigh on impossible to match is at best a bit disingenuous. It was my job to make sure that those I taught sold Ford trucks to the best of their ability, and I taught them never to disregard the other trucks with arrogance but to present the Ford trucks in the best light. I have heard , and admonished salespeople for saying things to customers as if they have manure for brains for considering the competition's trucks.
Who said deplorable? Such polysyllabic condemnations are not necessary.
The GMT400s are deplorable off-road in anything serious, but the 900s have other reasons, not the IFS specifically, that cause issues.

Ford isn't the end-all, neither is Dodge, nor Toyota, Nissan :)fall:) or GM.
But...GM should be better.

I've driven all of the current offerings. Not just on a test drive, actual miles.
I still have a GMT400 and spend way too much time up north in the same area as Extreme.

If I had a dream new GM HD it would have wider fender opening so I can fit taller/wider tires with out a lift, HD steering components that don't flex (even the 900HDs are too weak), a better upper/lower control arm and shock pairing so that the complete range of travel can be realized, ideally a progressive coil-over shock arrangement, an optional torsen front diff and rear limited slip with an electric locker. Add a factory skid plate on the DEF tank (they said there were no instances of stone impingement in testing), a band of reinforcement to the doors at the bodyline molding to reduce flex and door-dings and seats that don't break down as easily. Too many 900 seats feel like a recliner, I'd rather have a more command seating position and seat.

I'm not sure how to get around the low bumper, limited approach angle and the tire issue without sheet metal changes, so I'm not holding my breath. But for all the 400s faults, it is still pretty decent from the approach angle stand point. Plus, with 285s, it looks acceptable.
My tires stick out a little bit on the sides, I guess that's why the factory flares where installed on the 400s, right King Elvis?
 

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For the life of me I can't understand why GM has a 6.0 and then also a 6.2. In terms of horsepower, the V6 will be making what the 6.0 made six years ago. Why not just offer a std V6 with a 4.10 axle on 3/4 tons like they used to do with the 292 in the 70s and 80's. Get yourself some HD cooling and you're set. You've got all the torque multiplication in the world with the 6spd's 4:1 first gear.
4.56s to get them moving, but I see your point.
I believe it is about the over 8600 GVWR emissions certifications.

Really though it isn't about horsepower as much as Torque and the emissions in these HD applications.
The Duramax was 300hp too, elevation issues aside, I'd still take the 520 lbs.ft. 300hp Duramax over the 6.0 and 300+ hp V6.
 

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What I would like to know from most of you guys, is why do YOU think the superduty sells so well?
Customer loyalty, the IDEA that Super Duty trucks are better and the looks.

Like them or not, the Super Duty has been a HD looking truck, from day 1. It looks bigger and tougher.

Once we get into the emotional aspects of trucks, the quantifiable aspects go out the window.

This is what I mean by GM should be dominating the HD trucks, but they don't. So even if they are better, people aren't buying them like they buy Fords. This is where all the staged frame-twist tests, the towing tests, and the acceleration tests look silly when Ford has real people doing actual work with their Ford trucks for advertising. Sure it is staged, just like with GM, it just LOOKS better the way Ford does it.
Die-hard Dodge people won't switch to GM, so just write them off. Dodge is one to watch, as are the imports, but Dodge has been slowly notching away at the HD sales. They stumbled a bit with the lower fuel economy and power compared to Ford and GM, a by-product of no selective reduction, but they fill a niche that is growing.

With the 4:1 first gear you ...
I agree. The problem as I see it is similar to the old 4.3 HD. Even though in concept and application it was a good alternative, the reality of it was that in real-world testing, there was little advantage to the 4.3 HD over a 350HD, and plenty of advantages to the 350HD over the 6. The more modern 6 doesn't have a huge advantage, with less low-end-torque than the old 4.3, so I still submit that 4.56s will be needed to keep the RPMs high and get 20,000 lbs of GCWR moving. Let's face it, you and I both know that they will be loaded like that. We've all done it, overload the gooseneck and pray the DOT guys don't notice.

Also, little known fact is that the above 8501 GVWR vehicles will have to start improving gas mileage for the first time per latest CAFE regulations. It's not under the old CAFE "average" but is instead an index of the payload capacity so that lower payload trucks will need to get higher gas mileage. It's more complicated than the old CAFE regime (although even now that's not really an average anymore either but based on 'footprint' index of wheelbase x thread width) but they will be coming under at least minimal fuel economy regs where they haven't before.
True, again, to a point. The CAFE mandates for HD trucks are more designed to eliminate the incentive to build large, HD SUVs. Some Expeditions and the 3/4 ton Suburban were skirting the old rules. Pickups have a much higher load rating (payload, towing, etc) so they aren't impacted nearly as badly.
Make no mistake about it, the strict diesel emissions regs drove the price of a diesel engine option so high that it fueled a resurgence of the big gasoline engine, which is driving down the average fuel economy.
 
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