Alignment question?

[jbusby]

I put on a leveling kit, then went to get it aligned and my caster was 3 degrees on one side and 2. 5 on the other. They said this was in spec. I questioned why the . 5 degree difference and I was told it was to compensate for the crown of the road?! I can't understand that logic. Is it true? or is this guy talking out of his a@*? I'm running Nitto's 325/60-18 on Mickey Thompson Classic II's

 

[BHolm]

I would have prefered mine a little closer as well. His logic is fine except he forgot to take into account the CTD spending most of its time in the left lane I would never align a vehicle to account for the crown of the road, that is a moving target. . 5 degrees of caster wont likely cause a problem though.



Take it and drive it on your regular routes. If it wanders to one side or the other take it back and insist they do it again.

 

[DBraunig]

I agree, . 5 degree won't hurt anything. As long as the truck drives straight i wouldn't worry about it. We have some real @#$%^ roads in the hills of KY, so we have been know to "play" with caster to get a truck to drive straight around here.



Dave

 

[Devan Manis]

He's not making things up, do as Bholm says, caster won't cause any wear, if thats what your worried about.

 

[JayWm]

It is very common for vehicles to be aligned with a caster spread leading toward the left. The vehicle will want to go toward the lower caster number. Depending on vehicle type, brand, etc. will dictate how much caster spread to set the veh up with. What you didn't mention is which side is 2. 5 and which is 3. 0. Some veh spec's have a built in spread from the manufacturer, others do not. A half degree is nothing to sweat, sadly if you take it to Dodge if its in spec they will most likely be unwilling to do anything. Part of the problem is that as of yet, I am not aware of any kits, parts, etc that allow you to change caster offset on a 3rd gen truck. You can only raise or lower caster equally on both sides. By the way my truck has a half degree caster spread and it drives real straight in the left lane @ 80mph. A good number of vehicles will drift toward the right if no caster spread is done. What are your camber readings? Camber can indirectly cause a pull as well. For instance, your truck has a caster spread of . 5 degrees, lets assume that it's to the left. Now if your truck has camber readings of 1. 0 positive on the left and 1. 0 negative on the right, both front tires would be leaning toward the right and in theory the truck would have enough camber pull that it would go toward the right and override the left caster spread. Ideally you want camber set equally and set to the exact spec to get best tire wear. It can be very frustrating to have to tell a customer that their vehicle is most likely going to drive a certain way because the manufacturer did not give you provisions to change the alignment.

 

[jbusby]

JayWm,

You asked what the camber was set at. The camber is not adjustable right? The truck seems to track just fine so far. Thanks for the input.

 

[jwduke]

Can't they adjust camber by heating up the ends of the axle tube?

 

[Matt400]

my caster was 3 degrees on one side and 2. 5 on the other. They said this was in spec.

Thats not in spec and is not high enough. Your truck will track better with more caster.



Anyone who levels (2" in the front) should move the caster adjuster all the way forward. The fat offset side of the washer needs to be pointing to the front of the truck effectively making the lower track bar longer. Some shops don't want to mess with it during alignment and just set the toe.

You can do this yourself and then have a shop set the toe. The caster differential side to side is ok.



In this pic it is set up neutral with the fat side of the washer up. From here caster can be increased by rotating it forward 1/4 turn. We do alignments in our shop and have found on 4x4's that have 2" lift needs max caster dialed in for the spec to be within the DC recommended range.

 

[Midnight]

Never ever use heat on the front end suspension parts.

 

[JayWm]

JayWm,

You asked what the camber was set at. The camber is not adjustable right? The truck seems to track just fine so far. Thanks for the input.

You are correct, it is not adjustable... I was curious what left and right camber was. Like I mentioned in my first post, camber can cause a drift depending on what the camber readings are. I suspect that we will see the aftermarket come up with something to correct a caster or camber issue.

 

[JayWm]

Never ever use heat on the front end suspension parts.

Never, never, ever bend a late model axle. Old school ford I beams could be bent, but that was at least 15 years ago.

 

[JayWm]

Thats not in spec and is not high enough. Your truck will track better with more caster.



Anyone who levels (2" in the front) should move the caster adjuster all the way forward.



We do alignments in our shop and have found on 4x4's that have 2" lift needs max caster dialed in for the spec to be within the DC recommended range.

Matt400, agree with you 100%. When I align pretty much any Dodge 4x4 I dial up max caster. Even stock height trucks drive better with more caster. I think it helps the crappy on center feel of these trucks. I have gotten to where I can test drive a truck and most of the time feel that the track bar is worn out just by how it drives.



Matt, don't ya just love how easy it is to have the cam's ride up and out of the guides on the control arms while trying to set caster. I have gotten to where I jack up the truck to get the weight off and dial up max caster, set her back down, set toe, center the wheel and go... .

 

[MNielsen]

jbusyb,

A difference from left to right should not exceed . 5 degree and if it pulls it will pull to high camber or low caster, caster is not a wear angle but it can pull. As far as return steer and high speed stability at least on regular vehicles the higher the caster the easier to return to center after a turn but can be harder to turn. Hope this helps.

 

[jbusby]

Thanks for your help guys, I'll take it back and have max caster dialed in. They said they would if I wanted it that way.

 

[ECappleman]

Moog has come out with new adjustable upper ball joints.

You are supposed to be able to adjust camber with these.

 

[ADouglas]

I have a 06 2500 4x4 with a lift kit on it. Truck pulled left hard with only . 6 degrees more caster on the right side. Vehicle pulled left from factory and dealer told me could not adjust caster - camber under warranty because chrysler did not offer provision for adjustment. Brought vehicle to my own shop and performed allignment and found . 5 degrees less caster on left side. First thing i did was checked that both lower control arms where set equal to each other and they where. Cross rotated tires and problem did not go away. Found an adjustable upper ball joint made by specialty allignment products and installed 1 degree upper ball joint which I then was able to adjust camber-caster. car goes perfectly streight with 3. 2 left caster and 3. 3 right caster.

Point is that their is a way to adjust caster and camber. Usally vehicles with larger tires require less cross caster than vehicle with smaller ones. Back to the origanal question--- lots of vehicles come from the factory with about . 5 degrees of cross caster, common industry standerd is not to have more than . 5 degrees of cross caster or camber, if vehicle goes straight then don't worry about tire wear. I would be more concerned with the vehicle wondering at high speed because of the lack of caster on both sides. With larger tires you should have them turn both assentrics evenly to increase caster beause at 2. 5 degrees you vehicle may feel loose when driving at high speeds. more caster equells tighter steering feel

 

[JayWm]

ADouglas, can you shoot me the part numbers for the specialty alignment ball joints, I'm gonna have to climb on my supplier as I've been asking for months about something for the 3rd gen trucks. I use specialty's cams for trucks and like them much better than the northstars. Are you a tech?



Jay