DEATH WOBBLE?
#21
#22
RE: DEATH WOBBLE?
Yeah I was pulling my motorcycle on a trailer and hit a pothole on the highway sent it into a death wobble the guy with me thought we were going to diewe were doing like 70 and it stoped when we got down to about 35 scary stuff. I just ordered the luke's link and new sway bar links since one of them broke.
#23
#25
RE: DEATH WOBBLE?
There is already much good info in this post.
So that it will be available to someone doing a search in the future
I will paste in some archived info on what alignment settings to shoot for:
=====
Alignment programs (and service manuals I believe), give a wide
acceptable range for front caster on the 4x4 Rams. I believe the range
is 2 degrees to 5 degrees (if that's not correct, it's pretty close).
The problem occurs when the alignment tech (independent or dealer)
tells you that the measurements "checked out fine", just because they
were in this broad range of acceptance.
Caster readings that fall on either end of the scale are subject to
caster shimmy, even though they are "acceptable". I had to align some
30 trucks and attend a 9 hour "Dodge Ram Chassis Dynamics Diagnostics"
training session (fancy name, ehh?), before finding out that 3 degrees
to 4 degrees is the optimal caster setting for 4x4 Rams that eliminates
caster shimmy.
Below I will post what specifications I set Ram trucks to. First
I want to give a little more info on correct Ram alignments so you can
see if you had a job well done,
The eccentrics on the lower control arms ARE NOT for individual
wheel caster adjustments (even though our alignment machine says they
are). The eccentric sleeves in the upper ball joints are for adjusting
individual camber and total cross caster (difference in caster between
two front wheels). This is why replacement eccentrics are positionable
in eight different ways.
Once camber and cross caster are attained with the eccentrics, the
lower control arm eccentrics are then used to swing the caster readings
into specifications. The two eccentrics must be swung in the SAME
direction in EQUAL amounts. If they are not, it will create a setback
condition (one front wheel further forward than the other).
FYI - Comparing between the two front wheels, caster will cause a
pull to the smaller value and camber will cause a pull to the larger
value. A truck set up with caster pulling in one direction and camber
pulling in the other direction, can lead to a wandering truck; even
though it is "in specifications"!!!!!!
If the eccentrics on the lower control arms of your truck are not
pointing the same direction, the alignment was done incorrectly and the
axle was "twisted" or "forced" into position to attain the acceptable
values (seen them from the factory this way, go figure).
A correct alignment will set the truck up with a slight negative
cross caster (truck has slight pull to left) to compensate for right
hand road crown. Camber will be equal side to side slightly on the
negative side. This will help maintain acceptable camber when hauling
heavy loads, as the truck tends to lift in the front when towing.
Camber will then fall slightly positive when towing.
Just because the alignment shop says "it's in specifications", that
does not mean it is set up for proper performance and handling!!!!!!!!!
Specifications (my personal settings for every Ram I align): all specs
below are in degrees.
Left Wheel Right Wheel
-------------- ----------------
Caster 3.2 3.5
Cross Caster -.3
Camber -.10 -.10
Cross Camber 0.0
Toe - standard specs, (maybe a little out if you tow a lot, they will
pull in as the front end lifts up).
Brent
ASE Certified
Gold Certified Chrysler tech"
=================
kpzbee
He is 100% correct & don't let anyone tell you different. The only thing I
will add is that you will likely see the camber closer to 0 degrees on a 4X4.
That's where it's supposed to be. One other thing that most people check is
the rear axle alignment. To much of a thrust angle will also cause a pull
(push) in the front end. if it is out to far, the axle location will need to
be fixed since there are no adjustments. This is the kind of things I was
looking for with Intense's truck
========
92 Dak
I'm an auto tech that specializes in alignments and maybe I can help you out.
If the truck is pulling to the right the most probable causes are, the camber
is out, you have a tire problem or the caster is out. On the 4X4 there is only
one adjustment sleeve on the left side. This sleeve adjusts the toe in and
out. You can't have one side out and have it pull that direction. The caster
and camber are set first then the toe and then the wheel is staightened out
using an adjustment sleeve next to the pitman arm. There is no adjustment for
camber or caster on stock trucks. Moog now offers a caster-camber adjustment
sleeve the moves the stud of the upper ball joint to make corrections. Alot of
the Rams (4X4) have a tire wear problem on the outside edge of the right tire.
This is caused by to much camber and can be corrected by the Moog adjustment
sleeves. This positive caster will also cause the truck to pull to the right.
A vehicle has to be set up so that it offset roadcrown so it drives straight
in the right lane. The caster is always set to have more postive on the left
(usually 1 degree) and camber is set the same on both sides (caster won't wear
tires but camber will). Find out what the specs are and look at the camber
readings, they should be the same for left and right. Check your left tire to
see if it is wearing on the outside edge. If all the numbers seem to make
sense swap the tires from left to right and see if that help. If it pulls to
the left after the swap it's a tire problem, if continues to pull to the right
it's an alignment problem. Remember the old saying "keep it simple, stupid".
Rear axle problems are rare.
So that it will be available to someone doing a search in the future
I will paste in some archived info on what alignment settings to shoot for:
=====
Alignment programs (and service manuals I believe), give a wide
acceptable range for front caster on the 4x4 Rams. I believe the range
is 2 degrees to 5 degrees (if that's not correct, it's pretty close).
The problem occurs when the alignment tech (independent or dealer)
tells you that the measurements "checked out fine", just because they
were in this broad range of acceptance.
Caster readings that fall on either end of the scale are subject to
caster shimmy, even though they are "acceptable". I had to align some
30 trucks and attend a 9 hour "Dodge Ram Chassis Dynamics Diagnostics"
training session (fancy name, ehh?), before finding out that 3 degrees
to 4 degrees is the optimal caster setting for 4x4 Rams that eliminates
caster shimmy.
Below I will post what specifications I set Ram trucks to. First
I want to give a little more info on correct Ram alignments so you can
see if you had a job well done,
The eccentrics on the lower control arms ARE NOT for individual
wheel caster adjustments (even though our alignment machine says they
are). The eccentric sleeves in the upper ball joints are for adjusting
individual camber and total cross caster (difference in caster between
two front wheels). This is why replacement eccentrics are positionable
in eight different ways.
Once camber and cross caster are attained with the eccentrics, the
lower control arm eccentrics are then used to swing the caster readings
into specifications. The two eccentrics must be swung in the SAME
direction in EQUAL amounts. If they are not, it will create a setback
condition (one front wheel further forward than the other).
FYI - Comparing between the two front wheels, caster will cause a
pull to the smaller value and camber will cause a pull to the larger
value. A truck set up with caster pulling in one direction and camber
pulling in the other direction, can lead to a wandering truck; even
though it is "in specifications"!!!!!!
If the eccentrics on the lower control arms of your truck are not
pointing the same direction, the alignment was done incorrectly and the
axle was "twisted" or "forced" into position to attain the acceptable
values (seen them from the factory this way, go figure).
A correct alignment will set the truck up with a slight negative
cross caster (truck has slight pull to left) to compensate for right
hand road crown. Camber will be equal side to side slightly on the
negative side. This will help maintain acceptable camber when hauling
heavy loads, as the truck tends to lift in the front when towing.
Camber will then fall slightly positive when towing.
Just because the alignment shop says "it's in specifications", that
does not mean it is set up for proper performance and handling!!!!!!!!!
Specifications (my personal settings for every Ram I align): all specs
below are in degrees.
Left Wheel Right Wheel
-------------- ----------------
Caster 3.2 3.5
Cross Caster -.3
Camber -.10 -.10
Cross Camber 0.0
Toe - standard specs, (maybe a little out if you tow a lot, they will
pull in as the front end lifts up).
Brent
ASE Certified
Gold Certified Chrysler tech"
=================
kpzbee
He is 100% correct & don't let anyone tell you different. The only thing I
will add is that you will likely see the camber closer to 0 degrees on a 4X4.
That's where it's supposed to be. One other thing that most people check is
the rear axle alignment. To much of a thrust angle will also cause a pull
(push) in the front end. if it is out to far, the axle location will need to
be fixed since there are no adjustments. This is the kind of things I was
looking for with Intense's truck
========
92 Dak
I'm an auto tech that specializes in alignments and maybe I can help you out.
If the truck is pulling to the right the most probable causes are, the camber
is out, you have a tire problem or the caster is out. On the 4X4 there is only
one adjustment sleeve on the left side. This sleeve adjusts the toe in and
out. You can't have one side out and have it pull that direction. The caster
and camber are set first then the toe and then the wheel is staightened out
using an adjustment sleeve next to the pitman arm. There is no adjustment for
camber or caster on stock trucks. Moog now offers a caster-camber adjustment
sleeve the moves the stud of the upper ball joint to make corrections. Alot of
the Rams (4X4) have a tire wear problem on the outside edge of the right tire.
This is caused by to much camber and can be corrected by the Moog adjustment
sleeves. This positive caster will also cause the truck to pull to the right.
A vehicle has to be set up so that it offset roadcrown so it drives straight
in the right lane. The caster is always set to have more postive on the left
(usually 1 degree) and camber is set the same on both sides (caster won't wear
tires but camber will). Find out what the specs are and look at the camber
readings, they should be the same for left and right. Check your left tire to
see if it is wearing on the outside edge. If all the numbers seem to make
sense swap the tires from left to right and see if that help. If it pulls to
the left after the swap it's a tire problem, if continues to pull to the right
it's an alignment problem. Remember the old saying "keep it simple, stupid".
Rear axle problems are rare.
#27
yes iv done some research and believe that i have the death wobble, i hear that many people said MAX CASTER now when it comes to some things i know alot but this i know almost nothing is a max caster a part on my truck i already have or do i need to put one in,
IF I LEAVE THE DEATH WOBBLE ALONE WILL IT CAUSE DAMAGE?
Thanks for the help guys
IF I LEAVE THE DEATH WOBBLE ALONE WILL IT CAUSE DAMAGE?
Thanks for the help guys
Shaking occurs when a portion of the vehicle has a mechanical resonance frequency which receives energy from another connected source. This could be a multiple of the shake frequency, not just the identical wave frequency. e.g. The front end resonant frequency might be a multiple of the Tire rotation frequency or the engine / drive frequency.
The only solution is to change the shaking section (Usually the front-end suspension) frequency. This may involve significant modifications. The dampner appears to be a major factor. Use a new dampner with different characteristics which will dampen instead of amplifying the shake / vibration frequency of the front-end assembly.
Violent shaking will likely damage associated components resulting in additional expensive repairs.
#28
I FIXED MY DEATH WOBBLE TODAY! I it to the shop to have the castor adjusted as recommended my many of the forums. After the mechanic drove it he said it was not the castor. After checking it out he told me the PITMAN ARM and the IDLER ARM were so broken they were about to fall off the truck. They were both replaced. He did not touch the castor. I just picked it up and drove home. When I hit the bumps on the way home that always set it off nothing happened! As of right now there is NO WOBBLE!
#29
Re: death wobble
I have had good luck installing 1 deg. offset upper ball joints, performing an alignment (with max caster), and a steering box stabilizer. As long as your front end parts are all tight, these 3 things seem to fix the majority of death wobbles in my shop. http://rothautomotive.com
Last edited by rothautomotive; 08-03-2009 at 10:39 AM.
#30