748G-11 Gears Up
John Deere 748G-11 skidder, part of Deere's new line of G-11-series skidders, is getting
good marks from logging contractors for its new transmission.
By Paul MacDonald
Copyright 1998. Contact publisher for permission to use.
The 748G-11 grapple skidders from John Deere may be relatively new to the market, but
the machines are already proving themselves in bush operations in several parts of the
country, including Ontario and British Columbia.
John Deere JD 748G-11 Grapple Skidder
The G-11 series consists of five new skidder models - three grapple skidders and two
cable skidders. The new lineup retains the direct-drive powertrain, higher-horsepower
engines and the stable platform that have made the G-series a success in the market, says
One of the first contractors to work with the new 748G-11 was Herman Viel, who operates
in northwestern Ontario. His family is well established in the area. Herman's father Guy
started a contract logging operation in the region in the 1970s. Herman started working
with his father and then branched out on his own several years ago, doing contract
This past summer, Hen-nan Viel ran the 748G-11 in an operation located 100 km north of
Thunder Bay, near Armstrong, and was contracting to Mark Mrakic of Ground Zero Chipping.
Mrakic operates with a Peterson Pacific DDC 5000 chipper and was contracting for Avenor
with this cut, as well as hauling chips to Thunder Bay. In this operation, Viel was
skidding in wood that had been damaged in a fire in 1997.
The machine gets good marks for power from Herman Viel and his operators. "We're
very happy with the kind of power and torque that we get from the machine," says
Viel. The 748G-11 is at the top of the improved line in terms of power, which is supplied
by a John Deere 6076T diesel engine with maximum torque rise of 35 per cent at 1,350 rpm.
This gives an operator 532 ft.-lbs. of pulling power on a wheelbase of more than 12'on the
The 748G-11 came with a package that Ontrac Equipment Services (formerly Wood-Land
Tractor), the Deere dealer for Ontario, says is essential to operating in northwestern
Ontario. The package includes T1 steel underbelly pans to protect against rocky
conditions, and differential guards. "Without that, contractors would be looking at
damage within the first week given the rocky conditions they are working in," says
Tom Trembath, sales representative of Ontrac Equipment. "It's a very necessary
package and in the best interest of the contractor because it helps to keep the machines
up and running."
"Contractors here aren't that different from anywhere else," explains
Trembath. "Logging equipment is expensive these days and they want to keep it
operating as much as they can, with as much of the maintenance taken care of for them as
possible. We're talking about operating in some rugged conditions in this part of
Ontario." Maintenance is certainly a consideration, but generally the less the
contractor has to do, the better, he says. "They want to be able to run the heck out
of their machines in terms of hauling wood.
"The key is focusing on your uptime, not your downtime. Contractors can't afford
to have equipment down, which is also where having a good parts and service base plays
into the equation." To draw a comparison, says Trembath, equipment time is a
perishable quantity. Once production time is lost on a machine, it can't be made up again
- revenue that could have been realized if the machine had been operating is lost.
Vernon, BC contractor Keith Balcaen knows all about uptime - his 10 skidders were able
to achieve an uptime rate of 98 per cent last year, he says. "I fink we've got one of
the best preventative maintenance pro grams in BC."
Balcaen harvests 350,000 cubic metres a year, with operations in the Okanagan for
Riverside Forest Products, and further north in BC's Central Interior for Northwood
Timber. He took delivery of two 748G-11s from BC John Deere dealer Coast Tractor this past
summer and is enthusiastic about the machines. "They're probably the best grapple
skidder on the market," he says.
Balcaen points out three main improvements of the G-11 over its predecessor - the extra
power, the tilt cab and the transmission. "The reverse speeds in the other
transmission were too high and you could power it out," he says, also pointing out
the improved gear spacing in the forward speeds as a plus. The DF-180 transmission offers
more working gears in reverse, with a lower first reverse for better torque when backing
up slopes. "The new transmission is also much smoother shifting, which should result
in a better life for our powertrains."
The new DF-180 direct-drive powershift transmission, developed by John Deere's Funk
Division for all five G-11 skidder models, is a countershaft design, as opposed to the
planetary system in the G-series skidders. The new design serves up eight forward and
seven reverse speeds, with a microprocessor controlling the shifts, smoothly and
consistently. Spacing is even through the first six forward gears to better match engine
rpm to the load and make it easier for the operator to always find the fight gear.
The new transmission system also has an inching clutch pedal mechanism that requires
significantly less effort to actuate, and has improved modulation. This results in a pedal
that is easier to use and offers a smooth action throughout the clutch travel, says Deere.
Lubrication and cooling oil systems service the new inching pedal.
With narrower travel speeds in the lower gears, operators can more effectively and
smoothly run in second and third gear and improve their travel times, resulting in a few
more trips a day between the bush and roadside, says Wood-Land Tractors' Tom Trembath.
"Cycle times are of course key to the overall efficiency of the skidding
A new extreme-duty axle has been developed for the 748G-11 and its sibling machine, the
648G-11, and is recommended for severe conditions, such as operating with chains in rocks
and snow with a high-capacity grapple. This new optional axle utilizes a heavy-duty
planetary carrier assembly designed to last up to four times longer than the standard
model. The axle is actually only an option outside of Canada, as the heavy-duty axles will
be standard on all 648 and 748 units sold in Canada.
Also new to the G-11 series skidders are oil-lubricated outer axle bearings,
eliminating the need for routine greasing. The bearings reduce the potential of axle
failure caused by improper maintenance. "Previously, these bearings had to be greased
manually every eight hours," says Trembath. "Deere has gone to a system where
the bearings are sitting in an oil bath and bathe themselves.
"This is part of making the machines as maintenance-free as possible so the
operator does not have to do as much at the end of his shift. For example, operators now
just have to grease the arch pins, the boom pins and the centre pins or about a dozen
grease points. On the 748G-11, there are four less grease pins, which means 25 per cent
less maintenance in that area."
For Herman Viel and other contractors, the less time they and their operators have to
spend on maintenance, the more time the machine can be operating and skidding wood. After
a 12-hour shift, the operator can do a quick maintenance check of the machine and then
hand it over to the second shift operator. "These operators are paid to haul wood and
the more cords they haul to roadside, the more they get paid," says Trembath.
"It's all about production and keeping the machines working. It's as simple as
The 748G-11, like all the machines in the G-11-series, features a cab that tilts to
make it easier to access the transmission and to permit easy service of the components
located in the machine's mid-section. Using an onboard hand-operated hydraulic pump, the
operator can fully tilt the cab in about 15 minutes.
Hydraulics on the 748 G-11 include a new pump with an increased capacity of about 10
per cent. The pump now generates oil flow at 42 gpm for faster response times and overall
A new electronic monitoring cluster provides instant visual display of the condition of
16 vital machine functions. The system also has an audible alert when a function requires
immediate attention. The system includes LCD readout of engine speed, gear selection and
direction, and also provides transmission diagnostic data in the form of service codes.
Besides the mechanics, the operator's cab is an area where Deere, like all equipment
manufacturers, continues to do some tweaking to make further improvements. In areas like
northwestern Ontario and the BC Interior, where operators are looking at summer
temperatures in the high 20s and up-air conditioning not only makes for a more comfortable
operating environment, it is also likely to result in an increase in productivity. With
skidder operators at the controls 12 hours a day, keeping them relatively comfortable pays
"With the kind of summers we have in the BC Interior, it's not even a question of
getting air conditioning on our skidders," says contractor Keith Balcaen.