How would you like to have your trailer automatically steer
itself behind your truck?
The Truck that started is
all, GMC Denali Quadrasteer.
to chat or
learn more about the advantages of 4-Wheel-Steer.
This is so exciting it's hard to explain! I
wouldn't have believed the deference if I didn't drive it. In my decades of
pulling trailers, I thought I had seen it all. It's good to be pleasantly
surprised. I put the trucks with trailers through my extreme tests and
couldn't get the trailers to whip or dip. The Suburban with the Autoride
option was even more impressive. I took the Quadrasteer's on sharp mountain
curves and loaded round bales more to the rear of a flatbed trailer to
purposely make the trailer sway. That didn't work either. I did these
trailer tests on pavement and gravel roads. Each time I tried to make the
trailer misbehave, Quadrasteer controlled it.
The Most Important
Improvement to Pulling Trailers since the Weight Distributing Hitch
Delphi Quadrasteer electric rack
and pinion steering axle.
|It's all about control
and safety. Pulling loads in heavy traffic can be scary. And then there
are the maneuverability advantages like parking lots. Most mall seem to
have designed the parking lots for mini-cars, let alone large trucks.
We had "crab steer" tractors
back in the sixties. The 4x4 Case 1200, 1470 and 2670 series tractors would
steer the wheels front and rear in the same direction or the opposite
direction to turn shorter or offset the draft farming with a one-way plow.
It worked great and was controlled by the driver. In the nineties some
sport car manufactures introduced All-Wheel-steer cars for improved
cornering and parking. The problem that caused them to be discontinued was
the hydraulic activation. Being controlled by hydraulics, (oil under
pressure) these systems would move at different speeds depending on warm the
oil was. When cold the steering was slow and faster as it warmed up. That
wouldn't be much fun waiting to warm up each time have a similar
Delphi announces a reduced
price of $1995 for their Quadrasteer option on GM trucks for 2004 models.
Now enter Delphi, the electronic
guru's. Delphi has corralled the missing links in the Four-Wheel-Steer
equation. Using dependable electronic controls instead of inconsistent
hydraulic pressure, Delphi has created a safe, heavy-duty system for
ultimate vehicle control. Delphi has earned a reputation for top notch
electronic controls in the automotive industry, winning contracts with all
the manufactures for quality electronics. The best company for the job
designed the best system for the job. With safety first, Delphi created a
system that could correct itself should a problem arise. With a fail safe
neutral, the Quadrasteer unit will return to a stationary straight ahead
position if a wire is cut or unplugged returning the truck to "front
wheel" steering only.
(Excerpt from my Quadrasteer article)..."On with the good stuff and itís some very fun good stuff! I may have to
turn down the week I get the Hummer 2 just so I can get a Quadrasteer again.
The GMC HD 1500 was a pleasure to drive in traffic with the added driving
control that the Quadrasteer system hands you. ........... Iíve not in my many decades driven a better trailering vehicle.
Quadrasteer is designed to turn the rear wheels in the opposite direction as
the front wheels when driving under 40 mph and it turns the rear wheels the
same direction as the front wheels above 40 mph.
And in tow mode in
Four-Wheel-Steer the rear wheels turns less under 25 mph and more above 25 mph
for that great highway speed control...........For
an extreme test I hooked the Suburban to a car trailer ... with three big round bales. I loaded it on purpose heavy to
the rear for the test to provide some sway action....So somewhere close to 5000#ís of
trailer cruising down the old highways of Eastern Colorado at near 80 MPH. I
performed evasive maneuvers, (you know swerving between the white dashes in
the middle of the road). I couldnít get the trailer to move, sway, buck, or
even give a little! It was like the trailer and truck were one unit. The
trailer realigned itself behind the Suburban quickly as the Quadrasteer
walked sideways as I swerved back and forth trying to find a weakness.
never seen anything like it. Yes Iím in love! I did this on loose gravel
roads also and it handled more than superbly. My test with the Quadrasteer
turned off, scared me to death on pavement and gravel! ........... I donít suggest you pull a trailer 80 mph, but I know with
75 mph speed limits on Colorado primary highways, there are some of you that
do pull this speed and I want to be able to report on this trucks ability to
pull in the real world."
Delphi Engineer Kevin LaVigne
Straight from the engineer's mouth, Kevin
LaVigne of Delphi answered some questions for me on the phone. There have
been several good articles written about Quadrasteer and Delphi's website
does a great job of explaining the details involved at
I ask the questions I haven't seen anywhere.
MT: Is Quadrasteer different from the cars
that had all-wheel-steer in the early nineties?
KL: Yes, Delphi's QUADRASTEER
Four-Wheel-Steering System is electronically controlled whereas the earlier
four wheel steer systems were mechanically. Earlier systems also turned the
rear wheels at a smaller angle. QUADRASTEER has been designed to turn at a
large angle, up to 12 degrees, specifically for full size vehicles.
MT: Are the CV joints in the rear Dana 60
axle with Quadrasteer, heavy duty?
KL: Yes, the quartershaft assembly has a
tripot joint which allows the assembly to withstand torque levels similar to
HD 2500 applications. The ring gear in the rear axle is a 9 3/4 inch.
MT: Can you use overload springs on the rear
axle with Quadrasteer?
KL: Overload springs or air bags have been
used with QUADRASTEER. When making changes to your vehicle such as this
though, you may be voiding your warranty. Be sure to check with your GM
MT: Do you have to align all four wheels with
Quadrasteer as you would with a front wheel drive car?
KL: A vehicle equipped with QUADRASTEER can
become misaligned in the rear. There is a mechanical alignment required. The
only mechanical adjustment is the toe setting. The caster-camber is
non-adjustable. A quick electrical alignment is also required and must be
done by a GM qualified service technician.
Take a test drive pulling a trailer. More
dealers are understanding the value of a trailer test drive and
uses conventional front-wheel hydraulic power steering in combination with
an electrically powered rear wheel steering system, to adjust rear-wheel
angles, turning them opposite to the front wheels at lower speeds and in the
same direction as the front wheels at higher speeds, for amazing
maneuverability and control. At lower speeds, the system reduces
curb-to-curb turning diameter by 21% to 37.4 ft., which is about the same as
a compact car. You'll love them in parking lots. At highway speeds,
Quadrasteer reduces yaw to improve stability, providing safer, more
confident, lane changes, passing and evasive maneuvers, especially in wet or
windy conditions. The increase in trailering control is equally amazing.
With Quadrasteer, truck and trailer move down the highway almost like a
single unit. You can change lanes more quickly and safely with hardly any
trailer sway even at 70 mph with a 6,000-lb. trailer.
Read my article on
the Quadrasteer Suburban and GMC HD 1500 Click...
www.QuadrasteerClub.com to chat or
learn more about the advantages of 4-Wheel-Steer.