TRAC traction. Does it affect mileage??

Howdy. I've asked this of several people who own Saturns, and nobody can tell
me the advantage/disadvantage of having the Trac traction switched on versus
turning it off. I usually turn it off, because the light annoys me, but if I
were on slippery roads, I'd use it.
But does it have any effect at all on the mileage? The traction advantage
seems so minimal when you know what you're doing behind the wheel. Snow isn't
the problem it's made out to be, but this Traction thing looks like it's mostly
a useless bell/whistle, like the switch that makes it shift differently. I've
never noticed a difference there, either.
Tedrick

 

Simply put, traction control prevents wheel slippage by applying brakes and
reducing power to the specific slipping wheel so that that all wheels keep
good traction on the road. I have never heard of TC affecting mileage at
all. TC is great if you want more traction on rainy, snowy, or any road
conditions. By improving traction, you basically improve your handling too.

What TC does affect is your speed. Naturally, if TC needs to slow down a
misbehaving wheel, ie: you are street racing and want your wheels to spin,
then you would want to turn TC off. Otherwise, TTC does work and is intended
to be completely invisible to the driver as it does it's job.

marx404

 

Howdy back at you -
afik the traction control on my '01 lw300 does not affect the engine or
shifting under normal circumstances. What it does do when it detects a wheel
slip (on acceleration) is to apply the brake to the slipping wheel. This
attempts to divert power to the wheel that still has traction and to regain
traction on the slipping wheel. If this is not successful, the engine power
is cut back until the wheel slip is eliminated. The dashboard 'low traction'
indicator will come on for either of these conditions. There is no need to
let up on the accelerator since this is automatic.

Wheel slip is detected by sensing wheel RPM on all wheels and comparing
results. Wheel rpm is affected by the wheel radius and radius is a function
of tire pressure. What is important to keep in mind is that you should
always use identical wheels and tires, keep the inflation to spec and rotate
the tires on schedule to keep the radius on all tires identical. If you have
a tire that is starting to run flat, then it is a good idea to switch off
the traction control until your fix the flat. (of course, never drive on a
flat tire unless you want to buy a new tire and wheel).

Where I see the traction control coming on mostly is in wet weather when the
car starts to hydroplane. Also on heavy acceleration for passing, I get much
better stability with the traction control enabled. Compared to the minivan
I used to drive, the lw300 is a muscle car and the ABS/TRAC systems are well
appreciated.

Keep the bugs off the bumper and the shiny side up y'all.
Oppie

 

No need to let off the accelerator? So I can just keep going as usual and
it
will compensate for me? Cool...

Usually I use the LOW TRAC as an indicator I am on an ice patch and let off
the gas, then accelerate slowly from a stopped postion.

I've got a Blue '03 Ion QC w/ body kit.

 

I always recommend that you read the owner's manual (took me 3 times through
to get all the significant details). There is a lot of information there
about the correct operation and care of your vehicle. Take some of it with a
grain of salt and others as the gospel truth. (you decide with the filter of
experience)

The automatic compensation of throttle in a low traction event may vary from
vehicle to vehicle. The L300 is a drive by wire and the computer actually
controls the throttle. The accelerator pedal talks to the computer and has
no direct mechanical connection to the throttle. (a bit strange at times).

In a low traction event, the L300 backs off the throttle. On non-drive by
wire cars, the engine power is reduced by retarding the spark timing. This
is not as effective as the computer controlled throttle. It does work but in
either case, for a prolonged loss of traction, it is best to lift your foot
slightly off of the pedal.

Oppie

 

I'm not sure how the non-drive-by-wire, but otherwise computer controlled
engines throttle back. Retarding timing would be one way, reducing or
cutting off injectors would be another way.

Anyone out there in Saturn land *KNOW* how the computer throttles back the
engine in this case?

 

We had a couple of inches of good packing snow the other day. On the way
home from work, on the parkway which had not been plowed or salted yet, the
surface was slushy. The lw300 was handling just wonderfully even with the
uneven and slick surface. At about 40mph, I turned off the trac switch. The
handling suddenly became much more unstable and I had to very carefully
compensate for every furrow and puddle. Switched the traction control back
on for the remainder of the trip home. Even changing lanes from a well
traveled surface to an un-traveled one was nice and smooth.
Got to love technology when it works properly.
Oppie

 

Don't know about the gas mileage aspect. I would suspect it does nothing but
"watch" the relative wheel motion. this uses very little power.

I had similar questions about the feature, as well. It's sorta newly
emerging Older technology for the masses and we are not used to the feature
or the display.

The feature TRAC is great! you hardly notice it, EXCEPT it removes all
slipping and sliding. Provides very crisp handling in tight turns, wet
roads, etc.

The advise I received was to go out and try to slip the wheels without the
TRAC and then put it on. This way you can feel the effect in a controlled
off-road situation and anticipate what it does in traffic. ...In the mean
time... leave it on!

 

Short answer is that Traction Control (if all is well) does not affect gas
mileage.
If you have one tire, especially a drive wheel, that is low on air, it might
fool the system into dragging a brake. Not entirely sure if this scenerio is
correct but could conceivably cause a loss in mileage. Bottom line is to
check tire inflation regularly and rotate tires on schedule for best
performance.
Oppie