Product Evaluation: Mack

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The fleet operator’s opinion
CCJ Product Evaluations are not performed by CCJ editors. They are done by a team of fleet equipment managers, chosen for their experience with the type of product being evaluated. Editors report evaluators’ opinions, not their own.

An evaluation is based on a driving test and design assessment (which sometimes involves some disassembly of the vehicle), followed by a discussion among the evaluators and manufacturer’s representative(s).

The manufacturer’s responses to specific, footnoted items are included in a box at the end of this article.

As always, CCJ welcomes your comments and suggestions.


According to Mack Trucks, the Granite Series is designed “for a variety of applications, including dump, refuse, mixer and vocational tractor applications” – Mack’s core market segments. There was no argument from CCJ’s evaluators, who judged these tasks reasonable for a platform of this type.

The Granite Series – built on a constant-height version of Mack’s RD frame – features new styling and low tare weight (as low as 13,900 pounds with the Cummins ISL engine option), with no sacrifice in strength, says Mack.

With a standard wheelbase of 210 inches, and a 108-inch bumper-to-back-of-cab measurement, the Granite comes standard with Mack’s E-Tech engine, with ratings from 300-460 hp, while Cummins’ ISL engine, with ratings from 310-330 hp, is optional.

A new line of Mack Maxitorque ES transmissions, with a wide variety of gear ratios and PTO options, is offered.

In addition, a 248-inch-wheelbase Granite Bridge Formula version is available for operation in areas of North America with strict bridge-formula weight laws.

First impressions count
During an initial walk-around, one evaluator approved of efforts to lighten the vehicle. “Every pound I can save on a truck is another pound I can haul,” he said. “And it is sharp looking. Paint and panel fit are great.”

The ever safety-conscious evaluators were pleased to see dipped side windows and an available, low “peep” window on the passenger side, for improved outward visibility. Breakaway, West Coast mirrors that fold on impact, forward and backward, also met with approval.

Evaluators liked the clean, open areas aft of the fuel tanks for mounting optional equipment, and appreciated Granite’s new Body-Link electrical interface, which uses an industry-standard, 21-pin electrical jack/plug system to create interfaces inside and outside the cab. According to Mack, the system allows body and equipment installers to plug into the chassis without splicing wires or cutting holes in cab panels. Moreover, the interface can tap into Granite’s V-MAC (Vehicle Management and Control) system, for functions such as remote throttle control, diagnostics and programming.

The rear-edge-of-cab exhaust mounting drew mixed reviews. One evaluator maintained that it was a good, solid, out-of-the-way mount. Another, however, noted that because the stacks protrude a little aft of the cab, he would not be able to mount a body as close to the cab and get as much forward weight transfer as he’d like.1

Farther back along the vehicle, the team praised the camelback rear suspension, which, they said, provides superior traction off-road. As one evaluator explained, “With an air suspension, when you get on really uneven surfaces, you can get one wheel in the air. If you don’t have differential locks for both drive axles, as well as an interaxle lock, you’ll have trouble getting moving.

“The camelback pivots and walks over most anything,” he continued. “All you need is the interaxle lock.” All evaluators, however, wished that the suspension’s trunion bushing were bronze with a zerk fitting instead of rubber, citing better long-term durability.2

Fuel and oil filters are grouped in one spot on LH side of engine. Fluid check points were found to be convenient, and accessory-drive adjustment easy.

Touring the engine room
Moving on to underhood considerations, evaluators found the hood itself easy to open, due to redesigned side latches and coil-type assist springs. “No gas struts here,” said one. “They’ve kept it nice and simple.”

Evaluators agreed that routine maintenance access is exemplary. All fluid-check points are within an arm’s reach, and accessory-drive adjustment requires no contortions. They especially liked the fact that the fuel and oil filters are grouped in one low spot. One evaluator, however, expressed concern that rear cylinder-head work could be a little tight. Another noticed that the Granite uses a new gear-reduction starter, which “has plenty of torque and is smaller and will be a whole lot easier to replace.”

The team agreed that hoses and wires are routed and secured thoughtfully, with little chance of chaffing over time.

Two items of special note are an easy-to-operate manual fuel primer, and a firewall-mounted air compressor governor. “That’s a great spot for the governor,” said an evaluator. “They’re usually a [pain] to get to.”

Get in and go
Turning their attention to the interior, evaluators found entry and egress eased by lower steps, but said they’d like to see a grab-handle built into the armrest.3 Although Mack has fitted the Granite with hidden hinges and door checks to keep them clean and reduce wear, evaluators said they’d prefer two checks per door for better durability.

Once inside, evaluators appreciated the mainly flat dashboard and simple, round gauges for their ease of cleaning – an important consideration for a vehicle likely to be operated in dirty, dusty environments. They also noted that the gauge cluster is easily removed for service by removing a few, exposed Torx fasteners.

“I like the low-mounted radio,” added one evaluation team member. “Overhead-mounted units tend to shine right in your face at night.”

The team found good interior ergonomics to be the general rule, and they liked the unit’s tilt/telescoping steering wheel (tilt-only is standard for now). But one evaluator wished for a little more rearward seat travel. Evaluators otherwise found the cab spacious with plenty of room for add-ons like PTO controls.

Dashboard is mainly flat with simple, round gauges for their ease of cleaning – an important consideration for a vehicle that’s likely to be operated in dirty, dusty environments.

Storage options, evaluators learned, vary with choice of interior trim level. They include: pockets integrated into the interior door panels and rear cab wall; an overhead compartment; a passenger seat with a storage compartment underneath; and a separate center console.

What looks like a glove box isn’t a storage area, but an easily accessed electrical center that houses fuses and circuit breakers, with the circuit legend affixed to the inside of the cover. “Sometimes, manufacturers don’t attach the legend,” said an evaluator. “Then it simply doesn’t stay with the truck. That adds up to time wasted consulting a service manual.”

The Granite used for the evaluation had a GVW of 73,000 pounds, including a Mac dump body filled with gravel. After driving the truck around Mack’s test facility, evaluators were hard pressed to believe the E7 engine was rated at only 300 hp.4 They were also impressed with the vehicle’s grade-climbing and creeping ability which, Mack says, was aided by the double-low-range Mack T310M transmission. Evaluators commented on how well the cab air/shock-absorber suspension soaked up shock and vibration.

Perhaps the highest praise for the Granite came from an evaluator who operates competitors’ trucks in his fleet. “This compares very favorably with the best of what’s out there. It’s a truck I could easily do my job with.”


The Mack Granite Evaluation Team:

George Husack Jr.
Manager
George Husack Inc.
Schnecksville, Pa.

Bob Renner
Equipment Manager
Haines & Kibblehouse Inc.
Skippack, Pa.

Lloyd Zimmerman Jr.
President
Zimmerman Carriers
Ephrata, Pa.

With special thanks to:
Clark Confer
Project Director – Granite
Mack Trucks, Allentown Pa.

Steve Ginter
Manager – Vocational Sales
Mack Trucks

Michael Kline
Product Manager – Product Strategy & Planning
Mack Trucks

Mike O’Neill
President
O’Neill Public Relations
Yardley, Pa.


Standard Granite specs
(Note: Some specs may vary from evaluation truck)
Wheelbase: 210 inches
Engine: Mack EM7-300 E-Tech, 300-hp @ 1750 rpm, 1425 lb-ft torque @ 1020 rpm
Transmission: Mack T2060, 6-speed, 9.02:1 low; 0.60 high
Clutch: Eaton/Spicer CL 7891, 15-1/2-inch, ceramic, 2-plate
Front axle: Mack FAW18, 18,000 pounds
Rear axle: Mack SS38, 38,000 pounds
Front brakes: Meritor Q+
Rear brakes: Meritor Q+
Antilock: Eaton/Bosch 4S/4M
Fuel tanks: Round, steel, 55-gallon
Wheels: Accuride steel disc, 22.5 x 8.25
Tires: Goodyear G159A, 11R22.5


The manufacturer responds:

  1. Most Mack customers prefer cab-
    mounted exhaust to under-frame systems. Mack has tried to optimize the cab-mounted exhaust position, given the constraints of the cab dimensions.
  2. A bronze bushing with grease fitting is
    a regular option.
  3. The door-opening handle is built to withstand 250 pounds of pulling force.
  4. EM7-300 E-Tech engines are installed in Mack construction/vocational trucks. These are “Maxidyne” units, with extremely high torque rise, making the engine more powerful at lower rpm.