Caterpillar announced a significant refresh of its D8T track type tractor on Thursday. The iconic heavy dozer now has an upgraded transmission, a new blade cutting edge design, new ripper technology, a more durable undercarriage.
The new engineering brings double digit performance and efficiency improvements in almost every category, including 18 percent more material moved per hour using the same amount of fuel. And if you’re an operator, the control system along with improved differential steering and dedicated steering pumps makes it “As easy as driving a pickup truck” according to the company’s YouTube demonstrator.
Lock it up
One of the key drivers to the D8Ts efficiency is an improved four-speed torque converter transmission with a lock up clutch and planetary gears. The torque converter relies on fluid coupling to push the driveline in most conditions but automatically locks the clutch mechanically when maximum power is needed. Cat added an intermediate gear between first and second for smooth shifting when you’re trying to bring a load up to speed.
The transmission is fully automatic. You set the desired speed with a detented thumbwheel on the joystick and the transmission senses the load and makes the shifts for you. According to Sam Meeker, product application specialist for dozers and track loaders, the new transmission delivers up to 15 percent fuel efficiency improvements. “It took a lot of software and electronics to do it,” he says.
The transmission also informs another application with load sensing technology—the ripper. The automatic ripper control, what Cat calls Auto-rip 2.0, will raise the ripper teeth up out of the ground if it senses the tracks slipping. The ripper control also keeps the ripper bar parallel to the slope of the ground so you get equal engagement and even wear across multiple ripper teeth. In a similar fashion, Auto-carry will lift the blade up if the load on it exceeds the pushing power of the tracks, so track slippage is eliminated.
Cat offers a variety of blades for the new D8T, but the new Semi-Universal blade is taller, wider and deeper. It can carry 13.4 cubic yards vs. 11.3 yards on the old blade an improvement of 19 percent.
A new, optional “Performance Cutting Edge.” breaks the cutting edge into segments that approach the ground at different angles. These blade segments and side cutters break up material quicker than a monolithic cutting edge and will last as long as a regular blade without needing to be flipped, says Meeker.
The blade is also mounted closer to the body of the dozer for better balance. The Performance Cutting Edge will also be available for the D6 and D7 dozers.
For those of you who keep a sharp eye on undercarriage wear will be pleased to learn that the D8T has a new optional heavy-duty undercarriage with taller and harder “DuraLink” segments and larger bushings. All the bottom rollers are independently suspended which helps keep tracks planted on the ground and increases tractive effort.
The Cat literature claims 20 to 40 percent longer wear life and 25 percent more bushing wear life in abrasive conditions on this DuraLink undercarriage. Meeker explains that in soft dirt, the advantages are not as great, but in sandy or abrasive environment you should see a significant improvement. And in rocky and abrasive environments—the worst of all worlds for undercarriages—you’ll gain the most benefit.
Remote control ready
Cat showed us their remote control technology at ConExpo in 2017 and is building the new D8Ts to be remote control ready.
Installation of the RC components takes about a day. Then, with the wearable RC console you can “operate” the dozer up to 750 meters away as long as you have line of sight. A second option, using an RC station, can maneuver the machine from five miles or five thousand miles away, says Meeker—basically anywhere on the globe.
As befits this production oriented mover of mountains, the D8Ts come prewired for any level of machine control you desire. Meeker describes the offerings as Caterpillar’s technology ladder, which includes:
• The standard Slope Indicate system which simply shows you what your slope is on the monitor in the cab.
• Optional Cat Grade with Slope Assist, which sets the blade at the proper angle and keeps it there.
• Attachment Ready Option (ARO). Allows you to mount any brand of laser or GPS system to your dozer.
• Optional Cat Grade with 3D. This is a factory install that uses inertial measurement units and position sensing cylinders so there are no masts on the blades or exposed cables to worry about.
Engine and options
Cat’s C15, Tier 4 Final engine powers the new D8Ts. Power got a boost from 312 to 354 horsepower. In easier applications—light spreading, clean up—fuel economy gets an 11 percent boost. Drawbar pull to the ground increases up to 13 percent and overall productivity is up 19 percent, says Meeker.
You can order an optional rear camera for the new D8T and it comes standard with Product Link Elite telematics for remote troubleshooting, two way communication, software updates and real time operating information.
On the maintenance front, grouped service points and ground level access speed up daily and scheduled maintenance. The bottom guards on the underside of the machine can be opened hydraulically from one side or swung open bombay door style. A programmable automatic reversing fan clears debris from your radiator package.