From: msrdude on
I have a 96 corolla and my steering wheel moves kinda easily/
sensitive. Like my hands are not holding the steering wheel, and when
the light turns green, i press on the gas pedal and the steering wheel
moves right just a little bit. Also, when I get my car to drive
straight with my hands off the steering wheel, and I hit a little bump
(a bump i can and cant feel) the car doesn't drive straight anymore.
When I rock my steering wheel left and right, it moves kinda easy. My
other cars don't do any of this. I know its not an alignment problem
because I have aligned this car 4 times. When I hold the steering
wheel with my hands, it drives straight and i am holding the steering
wheel straight too. The problem is when I let go of the steering
wheel. Could it be a bad ball joint somewhere of something? that is
causing the steering wheel to be sensitive??
From: Ray O on

"msrdude" <kimiga(a)gmail.com> wrote in message
news:26198949-4925-40c5-84c6-89efc725cf09(a)j36g2000prj.googlegroups.com...
>I have a 96 corolla and my steering wheel moves kinda easily/
> sensitive. Like my hands are not holding the steering wheel, and when
> the light turns green, i press on the gas pedal and the steering wheel
> moves right just a little bit. Also, when I get my car to drive
> straight with my hands off the steering wheel, and I hit a little bump
> (a bump i can and cant feel) the car doesn't drive straight anymore.
> When I rock my steering wheel left and right, it moves kinda easy. My
> other cars don't do any of this. I know its not an alignment problem
> because I have aligned this car 4 times. When I hold the steering
> wheel with my hands, it drives straight and i am holding the steering
> wheel straight too. The problem is when I let go of the steering
> wheel. Could it be a bad ball joint somewhere of something? that is
> causing the steering wheel to be sensitive??

Hopefully, you do not routinely let go of the steering wheel while the
vehicle is in motion ;-)

Bad ball joints generally do not cause overly sensitive steering but it can
cause wandering. If the vehicle has been aligned many times, then whoever
is doing the alignment should have checked the condition of the ball joints,
and they should have brought bad ball joints to your attention.

I forget what the alignment readings were for your car, but the amount of
positive caster affects the tendency of the steering wheel to center itself.
More caster = more centering and more tendency for the vehicle to track in a
straight line.

A vehicle with front wheel drive can also exhibit a condition known as
torque steer, where the steering wheel has a tendency to pull to one side
(to the right in a Toyota) under hard acceleration. Torque steer is
generally not noticeable when you are holding on to the steering wheel
because of power assist, but if you let go and floor it, the steering wheel
should turn.

Besides alignment, tire inflation has a big effect on how a vehicle tracks.
If one of the right tires is under-inflated, the vehicle will drift to the
right.

Bottom line, hold on to the steering wheel when you drive and the car should
track in a straight line.
--

Ray O
(correct punctuation to reply)


From: Jeff Strickland on

"msrdude" <kimiga(a)gmail.com> wrote in message
news:26198949-4925-40c5-84c6-89efc725cf09(a)j36g2000prj.googlegroups.com...
>I have a 96 corolla and my steering wheel moves kinda easily/
> sensitive. Like my hands are not holding the steering wheel, and when
> the light turns green, i press on the gas pedal and the steering wheel
> moves right just a little bit. Also, when I get my car to drive
> straight with my hands off the steering wheel, and I hit a little bump
> (a bump i can and cant feel) the car doesn't drive straight anymore.
> When I rock my steering wheel left and right, it moves kinda easy. My
> other cars don't do any of this. I know its not an alignment problem
> because I have aligned this car 4 times. When I hold the steering
> wheel with my hands, it drives straight and i am holding the steering
> wheel straight too. The problem is when I let go of the steering
> wheel. Could it be a bad ball joint somewhere of something? that is
> causing the steering wheel to be sensitive??


I'm not a stickler for hanging onto the steering wheel, but I agree
completely that Caster Angle will make the steering twitchy, and you have
described torque steer. Low air in the right side tires (front or rear) will
make the car drift right, low pressure in the left will make the car drift
to the left. The crown in the road will make the car drift right, and
possibly counteract the effects of low pressure on the left side tires --
allowing the car to go straight sometimes and drift left others.

If you have a bad setting for the Caster Angle, then you might experience
Torque Steer more than you once did. Some torque steer is probably normal,
I'm not sure. It was a big problem for early implementations of small FWD
cars. The early Honda CVCCs had very strong torque steer to the point that
it was an objection to Americans that were accustomed to RWD. Anyway, if the
Caster is set poorly, Torque Steer might be more noticable than if it was
set correctly.



CASTER ANGLE
If you could draw a line that went through upper and lower ball joints and
included the exact center of the spindle, this is the line that determines
Caster Angle. If the line goes straight up and down, the angle would be
zero. Steering would be very twitchy, the tires would have no desire to
remain going straight ahead. If this angle was leaned towards the back of
the car, then the steering would become very stable and the tires would
resist moving away from straight ahead. If the angle was too steep, steering
would become difficult, so they try to find an angle that make the steering
stay straight, but is not so great as to make steering difficult.Think of a
motorcycle -- a crotch rocket and a chopper. The crotch rocket corners
really well, but it is twitchy -- it responds to changes in steering input
very quickly. The chopper has a very long front fork and a very flat
steering angle. The reasult is that it is great for going in straight lines,
but is difficult to turn. The steering angle (caster) on a bike is done by
the geometry of the forks and where they are fitted to the frame. Not
exaclty the same as the caster angle in your car, but the effects of a steep
or flat angle on the bike forks are similar to the Caster Angle in your car.

If the car has a very steep caster angle (the imaginary line is near
vertical to the ground) then the car will not work on its own to return to
straight line travel after a very sharp steering manuver. For example, if
you make a U-turn or back out of a parking spot and turn the wheel all, or
most, of the way, then want the car to go straight ahead, a car with a steep
caster angle will require you to physically turn the steering wheel back to
straight, but a car with a flat steering angle (more caster) will try to
return ot straight all by itself. If you have good caster, the steering
wheel will slide though your hands as you return to straight ahead travel,
if you have poor caster then you will have to physically turn the steering
wheel. A good balance would be that you might give the wheel a flick in the
direction you want it to go and it goes, and stops when you are going
straight.

If your car is willing to go in circles until you steer out of the turn you
puty it into, then your Caster is probably not set right.

I forget what the spec is, but I think you want your car set more Negative.
So, if the range was -3 to -7, -7 would be better to resolve this issue
and -3 is the direction to make twitchy steering more pronounced. If your
car is set closer to zero, see if they can set it away from zero, this
should resolve your issue, assuming you don't have wasted ball joints or
other significant suspension wear.



From: Ray O on

"Jeff Strickland" <crwlrjeff(a)yahoo.com> wrote in message
news:hrd4md$5fj$1(a)news.eternal-september.org...
>
> "msrdude" <kimiga(a)gmail.com> wrote in message
> news:26198949-4925-40c5-84c6-89efc725cf09(a)j36g2000prj.googlegroups.com...
>>I have a 96 corolla and my steering wheel moves kinda easily/
>> sensitive. Like my hands are not holding the steering wheel, and when
>> the light turns green, i press on the gas pedal and the steering wheel
>> moves right just a little bit. Also, when I get my car to drive
>> straight with my hands off the steering wheel, and I hit a little bump
>> (a bump i can and cant feel) the car doesn't drive straight anymore.
>> When I rock my steering wheel left and right, it moves kinda easy. My
>> other cars don't do any of this. I know its not an alignment problem
>> because I have aligned this car 4 times. When I hold the steering
>> wheel with my hands, it drives straight and i am holding the steering
>> wheel straight too. The problem is when I let go of the steering
>> wheel. Could it be a bad ball joint somewhere of something? that is
>> causing the steering wheel to be sensitive??
>
>
> I'm not a stickler for hanging onto the steering wheel, but I agree
> completely that Caster Angle will make the steering twitchy, and you have
> described torque steer. Low air in the right side tires (front or rear)
> will make the car drift right, low pressure in the left will make the car
> drift to the left. The crown in the road will make the car drift right,
> and possibly counteract the effects of low pressure on the left side
> tires -- allowing the car to go straight sometimes and drift left others.
>
> If you have a bad setting for the Caster Angle, then you might experience
> Torque Steer more than you once did. Some torque steer is probably normal,
> I'm not sure. It was a big problem for early implementations of small FWD
> cars. The early Honda CVCCs had very strong torque steer to the point that
> it was an objection to Americans that were accustomed to RWD. Anyway, if
> the Caster is set poorly, Torque Steer might be more noticable than if it
> was set correctly.
>
>
>
> CASTER ANGLE
> If you could draw a line that went through upper and lower ball joints and
> included the exact center of the spindle, this is the line that determines
> Caster Angle. If the line goes straight up and down, the angle would be
> zero. Steering would be very twitchy, the tires would have no desire to
> remain going straight ahead. If this angle was leaned towards the back of
> the car, then the steering would become very stable and the tires would
> resist moving away from straight ahead. If the angle was too steep,
> steering would become difficult, so they try to find an angle that make
> the steering stay straight, but is not so great as to make steering
> difficult.Think of a motorcycle -- a crotch rocket and a chopper. The
> crotch rocket corners really well, but it is twitchy -- it responds to
> changes in steering input very quickly. The chopper has a very long front
> fork and a very flat steering angle. The reasult is that it is great for
> going in straight lines, but is difficult to turn. The steering angle
> (caster) on a bike is done by the geometry of the forks and where they are
> fitted to the frame. Not exaclty the same as the caster angle in your car,
> but the effects of a steep or flat angle on the bike forks are similar to
> the Caster Angle in your car.
>
> If the car has a very steep caster angle (the imaginary line is near
> vertical to the ground) then the car will not work on its own to return to
> straight line travel after a very sharp steering manuver. For example, if
> you make a U-turn or back out of a parking spot and turn the wheel all, or
> most, of the way, then want the car to go straight ahead, a car with a
> steep caster angle will require you to physically turn the steering wheel
> back to straight, but a car with a flat steering angle (more caster) will
> try to return ot straight all by itself. If you have good caster, the
> steering wheel will slide though your hands as you return to straight
> ahead travel, if you have poor caster then you will have to physically
> turn the steering wheel. A good balance would be that you might give the
> wheel a flick in the direction you want it to go and it goes, and stops
> when you are going straight.

Not a bad explanation, but you should have stopped before you got to the
"good" and "bad" caster part because there isn't really such a thing.
Caster is either within the design specs or it is out of spec.


>
> If your car is willing to go in circles until you steer out of the turn
> you puty it into, then your Caster is probably not set right.
>
> I forget what the spec is, but I think you want your car set more
> Negative. So, if the range was -3 to -7, -7 would be better to resolve
> this issue and -3 is the direction to make twitchy steering more
> pronounced. If your car is set closer to zero, see if they can set it away
> from zero, this should resolve your issue, assuming you don't have wasted
> ball joints or other significant suspension wear.
>

Caster should;ld be positive, not negative.

The explanation implies that the more caster, the better, but there are some
negative consequences of lots of positive caster besides increased steering
effort, which can be overcome with more power steering boost. The more
positive the caster, the more the wheels will lay over when the steering
angle changes, and the more the wheels lay over, the greater the change in
how the tire tread contacts the pavement and the more noticeable the
difference in the variance in the height of the front of the vehicle.
--

Ray O
(correct punctuation to reply)


From: Jeff Strickland on

"Ray O" <rokigawa(a)NOSPAMtristarassociates.com> wrote in message
news:hrdqj4$6tt$1(a)news.eternal-september.org...
>
> "Jeff Strickland" <crwlrjeff(a)yahoo.com> wrote in message
> news:hrd4md$5fj$1(a)news.eternal-september.org...
>>
>> "msrdude" <kimiga(a)gmail.com> wrote in message
>> news:26198949-4925-40c5-84c6-89efc725cf09(a)j36g2000prj.googlegroups.com...
>>>I have a 96 corolla and my steering wheel moves kinda easily/
>>> sensitive. Like my hands are not holding the steering wheel, and when
>>> the light turns green, i press on the gas pedal and the steering wheel
>>> moves right just a little bit. Also, when I get my car to drive
>>> straight with my hands off the steering wheel, and I hit a little bump
>>> (a bump i can and cant feel) the car doesn't drive straight anymore.
>>> When I rock my steering wheel left and right, it moves kinda easy. My
>>> other cars don't do any of this. I know its not an alignment problem
>>> because I have aligned this car 4 times. When I hold the steering
>>> wheel with my hands, it drives straight and i am holding the steering
>>> wheel straight too. The problem is when I let go of the steering
>>> wheel. Could it be a bad ball joint somewhere of something? that is
>>> causing the steering wheel to be sensitive??
>>
>>
>> I'm not a stickler for hanging onto the steering wheel, but I agree
>> completely that Caster Angle will make the steering twitchy, and you have
>> described torque steer. Low air in the right side tires (front or rear)
>> will make the car drift right, low pressure in the left will make the car
>> drift to the left. The crown in the road will make the car drift right,
>> and possibly counteract the effects of low pressure on the left side
>> tires -- allowing the car to go straight sometimes and drift left
>> others.
>>
>> If you have a bad setting for the Caster Angle, then you might experience
>> Torque Steer more than you once did. Some torque steer is probably
>> normal, I'm not sure. It was a big problem for early implementations of
>> small FWD cars. The early Honda CVCCs had very strong torque steer to the
>> point that it was an objection to Americans that were accustomed to RWD.
>> Anyway, if the Caster is set poorly, Torque Steer might be more noticable
>> than if it was set correctly.
>>
>>
>>
>> CASTER ANGLE
>> If you could draw a line that went through upper and lower ball joints
>> and included the exact center of the spindle, this is the line that
>> determines Caster Angle. If the line goes straight up and down, the angle
>> would be zero. Steering would be very twitchy, the tires would have no
>> desire to remain going straight ahead. If this angle was leaned towards
>> the back of the car, then the steering would become very stable and the
>> tires would resist moving away from straight ahead. If the angle was too
>> steep, steering would become difficult, so they try to find an angle that
>> make the steering stay straight, but is not so great as to make steering
>> difficult.Think of a motorcycle -- a crotch rocket and a chopper. The
>> crotch rocket corners really well, but it is twitchy -- it responds to
>> changes in steering input very quickly. The chopper has a very long front
>> fork and a very flat steering angle. The reasult is that it is great for
>> going in straight lines, but is difficult to turn. The steering angle
>> (caster) on a bike is done by the geometry of the forks and where they
>> are fitted to the frame. Not exaclty the same as the caster angle in your
>> car, but the effects of a steep or flat angle on the bike forks are
>> similar to the Caster Angle in your car.
>>
>> If the car has a very steep caster angle (the imaginary line is near
>> vertical to the ground) then the car will not work on its own to return
>> to straight line travel after a very sharp steering manuver. For example,
>> if you make a U-turn or back out of a parking spot and turn the wheel
>> all, or most, of the way, then want the car to go straight ahead, a car
>> with a steep caster angle will require you to physically turn the
>> steering wheel back to straight, but a car with a flat steering angle
>> (more caster) will try to return ot straight all by itself. If you have
>> good caster, the steering wheel will slide though your hands as you
>> return to straight ahead travel, if you have poor caster then you will
>> have to physically turn the steering wheel. A good balance would be that
>> you might give the wheel a flick in the direction you want it to go and
>> it goes, and stops when you are going straight.
>
> Not a bad explanation, but you should have stopped before you got to the
> "good" and "bad" caster part because there isn't really such a thing.
> Caster is either within the design specs or it is out of spec.
>
>

Yes. Bad is not defined very well, I intended it to mean an angle closser to
zero, but it could also be an angle that is out of spec in the other
direction, but those symptoms would be greater steering effort, not less.


>>
>> If your car is willing to go in circles until you steer out of the turn
>> you puty it into, then your Caster is probably not set right.
>>
>> I forget what the spec is, but I think you want your car set more
>> Negative. So, if the range was -3 to -7, -7 would be better to resolve
>> this issue and -3 is the direction to make twitchy steering more
>> pronounced. If your car is set closer to zero, see if they can set it
>> away from zero, this should resolve your issue, assuming you don't have
>> wasted ball joints or other significant suspension wear.
>>
>
> Caster should;ld be positive, not negative.
>
> The explanation implies that the more caster, the better, but there are
> some negative consequences of lots of positive caster besides increased
> steering effort, which can be overcome with more power steering boost.
> The more positive the caster, the more the wheels will lay over when the
> steering angle changes, and the more the wheels lay over, the greater the
> change in how the tire tread contacts the pavement and the more noticeable
> the difference in the variance in the height of the front of the vehicle.
> --


Absolutely. I tried to explain that at the very first. One wants some caster
angle, and within the spec, further from zero is generally more desirable to
prevent a twitchy steering wheel. But you are absolutely correct that if
there is too much caster angle, that can be bad. One bad thing being that
tires simply lay over instead of turn. All of this stuff is planned out with
geometry, and there is a point where too much caster can become as unnerving
for the driver as too little, but for entirely different rerasons.

Whichever direction, positive or negative, zero is where the imaginary line
is perpendicular to ground. Negative 3 and Positive 3 are the same distance
from zero, just in opposite directions. So, if the spec is from 3 to 7, and
twitchy steering is the problem then the angle is closer to 3 than to 7. To
fix twitchy steering, one would want the angle moved (if that's even
possible) closer to 7 than to 3.

All of this talk about setting caster ignores the fact that caster is often
not adjustable, except by bending. Such as runing the car into curbs and
potholes.