Another Article on the H3 Alpha

[Desert Dan]

Another Article on the H3 Alpha

Popular Mechanics Article on the H3 Alpha

http://www.popularmechanics.com/blog...s/4213782.html

Case strength with an aluminum housing is always a concern,? Ehrlich insists. ?When the case deflects under load, the teeth of the ring and pinion don?t mesh properly and can fail.?

The iron housing should certainly fix that potential problem. Additionally, the front driveshaft is constructed from 30-percent thicker wall tubing to further beef-up the frontend. Hummer deemed the CV axles tough enough, and they?ll remain the same spec on the Alpha as the regular H3, as will the rear axle.

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Interesting reviews of article...

[RubHer Yellow Ducky]

Good reading...

[HummBebe]

Exclusive Details on New Hummer H3 Alpha: New York Auto Show Preview Yesterday we told you about the Hummer H3 Alpha to be revealed at the New York auto show. The big news? It will finally get the V8 engine. More specifically, the 295-hp, 5.3-liter V8.
The Hummer H3 is based on mechanical components from the 4WD Chevy Colorado/GMC Canyon pickups. The driveline in those trucks was never designed to handle the power and torque of a V8. So we were a little skeptical as to how things would hold up on the H3 Alpha under abusive off-road conditions.
Well, after a conversation this morning with H3 powertrain integration engineer Daryl Ehrlich, we have the full skinny on the new H3 Alpha?s drivetrain. First, to swap a V8 into the engine bay designed for small inline engines, Hummer had to modify the firewall sheetmetal for clearance. There?s also a new oil pan, exhaust manifold and ?lots of interface items? that needed to be changed for this application of GM?s 5.3-liter V8. To keep the engine cool on hot days out on the trail, there?s a new radiator with a new compact viscous clutch fan.
?We?ve specified the balance between fin density and cooling tubes to optimize the radiator for the V8,? says Ehrlich.
The drivetrain behind the V8 gets some significant upgrades too. The 4L60E four-speed automatic gets a new torque converter, and the Alpha has the same full-time 4WD along with 4WD high-range and 4WD Low with ultra-low 4:1 gearing as the regular H3. With all 315 lb.-ft. of torque from the V8 and that extreme low-range gearing (most 4WD trucks have low ranges in the 2.0:1 to 2.72:1 range), the differentials now have 4.10:1 gears instead of 4.56:1 units to ease stress on axles. Speaking of axles, what many would say is the weak link in the H3?s drivetrain gets some help in the Alpha: The aluminum front differential case is replaced with a new cast-iron one.
?Case strength with an aluminum housing is always a concern,? Ehrlich insists. ?When the case deflects under load, the teeth of the ring and pinion don?t mesh properly and can fail.?
The iron housing should certainly fix that potential problem. (Potential???? )Additionally, the front driveshaft is constructed from 30-percent thicker wall tubing to further beef-up the frontend. Hummer deemed the CV axles tough enough, and they?ll remain the same spec on the Alpha as the regular H3, as will the rear axle.
One feature Hummer actually removed from the H3 Alpha is the traction control disabling system. In its previous model, if the vehicle was climbing a boulder and you needed to brake with the left foot as you crested the rock to keep the vehicle under control, the traction control system would disable and leave you spinning momentarily. No more. Ehrlich says you can now two-foot brake as you climb an obstacle and the traction control will stay active. Cool.
On the street, Hummer says the Alpha will scoot to 60 mph in less than eight seconds. That?s about two to three seconds quicker than the Inline five-cylinder model. We?ll let you know how it all works when we drive the H3 Alpha in a few months. ?Ben Stewart