Alignment/Measurement Question - Caster of Front Wheels

I recently replaced upper ball joints on a '96 Dodge 3500 (1-ton) van.
This vehicle uses pressed-in ball joints, and I replaced them with a
standard C-frame tool. After a few months, one of the ball joints
backed itself out (this is a poor design, IMO). I pressed it back in,
and tack-welded it in a few spots. So far, it's holding just fine.

In order to do the weld, I removed the upper A-frame. Of course, I
didn't think to mark it's position (uses no shims, just slotted bolt
holes to adjust caster/camber) until I'd already loosened the bolts and
let things shift.

I'd like to get the truck properly in alignment. If that's not
possible, at least driveably close until I buy new tires and have a
shop fine-tune it.

I think I can measure camber with a plumb bob, and toe-in's a
no-brainer, but how in the devil can I measure caster?

Also, is there an online reference where I can find the alignment specs
for my vehicle?

best regards,

Martin

Go to dodgetalk.com,the ball joint problem is discussed often.Or often
disgusted.I am not certain about the vans but the late 90s trucks are a
real problem.I hope you have a moog and not a dodge ball joint

Martin wrote:
> I recently replaced upper ball joints on a '96 Dodge 3500 (1-ton) van.
> This vehicle uses pressed-in ball joints, and I replaced them with a
> standard C-frame tool. After a few months, one of the ball joints
> backed itself out (this is a poor design, IMO). I pressed it back in,
> and tack-welded it in a few spots. So far, it's holding just fine.
>
> In order to do the weld, I removed the upper A-frame. Of course, I
> didn't think to mark it's position (uses no shims, just slotted bolt
> holes to adjust caster/camber) until I'd already loosened the bolts and
> let things shift.
>
> I'd like to get the truck properly in alignment. If that's not
> possible, at least driveably close until I buy new tires and have a
> shop fine-tune it.
>
> I think I can measure camber with a plumb bob, and toe-in's a
> no-brainer, but how in the devil can I measure caster?
>
> Also, is there an online reference where I can find the alignment specs
> for my vehicle?
>
> best regards,
>
> Martin
>

Fundamentally, Castor is the angle of the "king pin axis" viewed from the
side, while camber is the angle of the wheel viewed from the front. You can
indeed set camber using a plain level and a ruler, I do it all the time on
my race car in fact. Castor is harder. I can think of a couple of fiddles
to get it close, but I'd personally take a truck to an alignment shop and
let them do it.

Fiddles: My race car has a flat machined on the upright so I just put a
digital level on and read the castor directly. You can measure castor
indirectly by measuring it's effect on camber as you turn the wheels,
usually 20 degrees left and right. You could probably get in the ball park
by measuring how far back the upper ball joint is compared to the lower
using your level and a ruler, and compare side to side. You could do it by
adjusting until the truck tracks straight - that has the advantage of
ignoring what the measurement actually is and gets the effect you want.

Brian

Brian




"MK1" > wrote in message
...
> Go to dodgetalk.com,the ball joint problem is discussed often.Or often
> disgusted.I am not certain about the vans but the late 90s trucks are a
> real problem.I hope you have a moog and not a dodge ball joint
>
> Martin wrote:
>> I recently replaced upper ball joints on a '96 Dodge 3500 (1-ton) van.
>> This vehicle uses pressed-in ball joints, and I replaced them with a
>> standard C-frame tool. After a few months, one of the ball joints
>> backed itself out (this is a poor design, IMO). I pressed it back in,
>> and tack-welded it in a few spots. So far, it's holding just fine.
>>
>> In order to do the weld, I removed the upper A-frame. Of course, I
>> didn't think to mark it's position (uses no shims, just slotted bolt
>> holes to adjust caster/camber) until I'd already loosened the bolts and
>> let things shift.
>>
>> I'd like to get the truck properly in alignment. If that's not
>> possible, at least driveably close until I buy new tires and have a
>> shop fine-tune it.
>>
>> I think I can measure camber with a plumb bob, and toe-in's a
>> no-brainer, but how in the devil can I measure caster?
>>
>> Also, is there an online reference where I can find the alignment specs
>> for my vehicle?
>>
>> best regards,
>>
>> Martin
>>

Turn the wheels full left and right and measure the camber change at each
position. The caster is 1/2 the difference if the wheels had turned to 90
degrees so you have to do some calculation there. Since you have one that
hasn't been changed, you can compare between the two sides and make them
equal. It is more important to have matched caster than an absolute value.

--
Why isn't there an Ozone Hole at the NORTH Pole?

Are you sure it was a press fit?? Most uppers in chrysler product
trucks & older rear drive cars are screw in. Mabee they changed the
design in the newer ones but if the joint has flat sides around the
top, it's a threaded situation, which would explain it not staying put.
I've welded quite a few of these that were stripped out with long
lasting success but always on the vehicle. The best way to get proper
alignment restored will be at an alignment shop. Good luck.

Geezus Christ, go get it aligned, cheapskate
JR
Dweller in the cellar
and next time, buy a Ford

Martin wrote:
> I recently replaced upper ball joints on a '96 Dodge 3500 (1-ton) van.
> This vehicle uses pressed-in ball joints, and I replaced them with a
> standard C-frame tool. After a few months, one of the ball joints
> backed itself out (this is a poor design, IMO). I pressed it back in,
> and tack-welded it in a few spots. So far, it's holding just fine.
>
> In order to do the weld, I removed the upper A-frame. Of course, I
> didn't think to mark it's position (uses no shims, just slotted bolt
> holes to adjust caster/camber) until I'd already loosened the bolts and
> let things shift.
>
> I'd like to get the truck properly in alignment. If that's not
> possible, at least driveably close until I buy new tires and have a
> shop fine-tune it.
>
> I think I can measure camber with a plumb bob, and toe-in's a
> no-brainer, but how in the devil can I measure caster?
>
> Also, is there an online reference where I can find the alignment specs
> for my vehicle?
>
> best regards,
>
> Martin
>


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"JR North" > wrote in message
...
> Geezus Christ, go get it aligned, cheapskate

That is what I was thinking too. Caster doesn't effect tire wear, but might
require the driver to grip the wheel with both hands to drive it to the
alignment shop.

Lane

Might want to check this site out. Lot of shops use it for the latest
information.

www.alignmentspecs.com

"Martin" > wrote in message
ups.com...
> I recently replaced upper ball joints on a '96 Dodge 3500 (1-ton) van.
> This vehicle uses pressed-in ball joints, and I replaced them with a
> standard C-frame tool. After a few months, one of the ball joints
> backed itself out (this is a poor design, IMO). I pressed it back in,
> and tack-welded it in a few spots. So far, it's holding just fine.
>
> In order to do the weld, I removed the upper A-frame. Of course, I
> didn't think to mark it's position (uses no shims, just slotted bolt
> holes to adjust caster/camber) until I'd already loosened the bolts and
> let things shift.
>
> I'd like to get the truck properly in alignment. If that's not
> possible, at least driveably close until I buy new tires and have a
> shop fine-tune it.
>
> I think I can measure camber with a plumb bob, and toe-in's a
> no-brainer, but how in the devil can I measure caster?
>
> Also, is there an online reference where I can find the alignment specs
> for my vehicle?
>
> best regards,
>
> Martin
>

pater wrote:

> Are you sure it was a press fit?? Most uppers in chrysler product
> trucks & older rear drive cars are screw in.

A lot of people *ruined* old Chrysler upper control arms by ASSuming
they were just like other brands and pressing the screw-in joints out
and new ones in.

However, Chrysler cheaped-out on the trucks in the 90s and did use
press-in joints.

Yes, they are definitely pressed in. The holes in the a-frames have
smooth sides, and there are "grip ridges" but no threads on the ball
joints. Some people look at the ball joints and think they are
screw-in because there are flats on the outer portion, but that's
deceptive. You'll quickly get tired of trying to unscrew them

Martin