4 Wheel Alignment or Front End Alignment?
I had to go look at the specs in my manual for the numbers and was a little surprised by some of them. For example, Caster is shown to be 3.4* on the left and 3.8* on the right. The difference being and adjustment for road crown. They also show that these numbers can be + or - 1*. But, I would suggest that the plus or minus number would apply to both side, together. Not having that much change being added to one side or the other. In other words, you wouldn't want a reading of say 4.4* on the left and 3.8* on the right even though the numbers are within specs. That would make no sense. I would have them set the caster to the recommended spec of 3.4* and 3.8*, same with camber, both set at -.10*. and toe (front) set at .10*, each side.
As far as you steering wheel being straight ahead goes, I would adjust the tie rods to compensate but, being as there is electronic steering involved, If and issue exist with this unit and is related to the steering wheel being straight, I don't know enough about this to give you a competent answer. Any way, get the front alignment taken care of first and then, do another measure to see where the rear toe/thrust angle is. Merely getting the front straightened out may get the rear in line. With your numbers posted, it's very slight as I said before but, it should be set at zero regardless. Who ever does the work will have to determine how to adjust the rear if it's still out. Nothing I can suggest on these newer vehicles may apply.
By the way, I'm assuming that your truck is the same model as mine or a Scab and a 4x4 of which the numbers are the same and the model years are comparable.
As far as you steering wheel being straight ahead goes, I would adjust the tie rods to compensate but, being as there is electronic steering involved, If and issue exist with this unit and is related to the steering wheel being straight, I don't know enough about this to give you a competent answer. Any way, get the front alignment taken care of first and then, do another measure to see where the rear toe/thrust angle is. Merely getting the front straightened out may get the rear in line. With your numbers posted, it's very slight as I said before but, it should be set at zero regardless. Who ever does the work will have to determine how to adjust the rear if it's still out. Nothing I can suggest on these newer vehicles may apply.
By the way, I'm assuming that your truck is the same model as mine or a Scab and a 4x4 of which the numbers are the same and the model years are comparable.
There are no adjustments in the rear. Thrust angle being off may be due to poor wheel sensor placement. I had caster that was outside spec on my last alignment, had them immediately put it back on the rack, caster was within spec.
As long as caster is close to the same angle on both sides, wear will be normal. How much caster you have, though, will impact the vehicle's natural ability to self-center, and can make the difference between being a joy to drive on the highway, and spending all your time correcting direction to remain within your lane.
As long as caster is close to the same angle on both sides, wear will be normal. How much caster you have, though, will impact the vehicle's natural ability to self-center, and can make the difference between being a joy to drive on the highway, and spending all your time correcting direction to remain within your lane.
There are no adjustments in the rear. Thrust angle being off may be due to poor wheel sensor placement. I had caster that was outside spec on my last alignment, had them immediately put it back on the rack, caster was within spec.
As long as caster is close to the same angle on both sides, wear will be normal. How much caster you have, though, will impact the vehicle's natural ability to self-center, and can make the difference between being a joy to drive on the highway, and spending all your time correcting direction to remain within your lane.
As long as caster is close to the same angle on both sides, wear will be normal. How much caster you have, though, will impact the vehicle's natural ability to self-center, and can make the difference between being a joy to drive on the highway, and spending all your time correcting direction to remain within your lane.
This is the final alignment angled
The rear has nothing that is adjustable and it looks like your axle is slightly shifted. But honestly with the way they left your caster so messed up I question the competence of this alignment technician. Indeed caster is not a primary cause of tire wear but it certainly will ruin tires when it’s so far off that you need to steer the wheels to compensate!
Last edited by Julio Perdomo; Aug 17, 2020 at 07:17 PM.
Keep in mind, that rear thrust angle is just 7/10's of a degree. I question the ability of many alignment machines to measure that accurately to a tenth. Most look like they've had two or three three decades in the shop. When was the last calibration done?
Any alignment tech worth his/her salt will wipe down the wheels and check for high spots due to impact before mounting the sensors. Most aren't worth my shaker of table salt. That 0.2º difference between readings comes out to 1.5mm difference between where the sensor mounts on opposite sides of an 18" rim. That's well within the tolerance of a nice whack against aluminum with a hard object, or the tech not ensuring the sensor was fully seated.
Any alignment tech worth his/her salt will wipe down the wheels and check for high spots due to impact before mounting the sensors. Most aren't worth my shaker of table salt. That 0.2º difference between readings comes out to 1.5mm difference between where the sensor mounts on opposite sides of an 18" rim. That's well within the tolerance of a nice whack against aluminum with a hard object, or the tech not ensuring the sensor was fully seated.
Keep in mind, that rear thrust angle is just 7/10's of a degree. I question the ability of many alignment machines to measure that accurately to a tenth. Most look like they've had two or three three decades in the shop. When was the last calibration done?
Any alignment tech worth his/her salt will wipe down the wheels and check for high spots due to impact before mounting the sensors. Most aren't worth my shaker of table salt. That 0.2º difference between readings comes out to 1.5mm difference between where the sensor mounts on opposite sides of an 18" rim. That's well within the tolerance of a nice whack against aluminum with a hard object, or the tech not ensuring the sensor was fully seated.
Any alignment tech worth his/her salt will wipe down the wheels and check for high spots due to impact before mounting the sensors. Most aren't worth my shaker of table salt. That 0.2º difference between readings comes out to 1.5mm difference between where the sensor mounts on opposite sides of an 18" rim. That's well within the tolerance of a nice whack against aluminum with a hard object, or the tech not ensuring the sensor was fully seated.
I meant, when was the alignment machine last calibrated.
There is no reason for the steering wheel to be off center, even with a bent frame. Simply a matter of spinning both steering tie rods the same amount to get the steering wheel centered. Alignment will remain the same. I've fixed that myself on a few occasions, it taking much longer to get them to just pull it back into the bay than to adjust myself in the driveway. Fortunately, my current shop takes care of that like they should.
There is no reason for the steering wheel to be off center, even with a bent frame. Simply a matter of spinning both steering tie rods the same amount to get the steering wheel centered. Alignment will remain the same. I've fixed that myself on a few occasions, it taking much longer to get them to just pull it back into the bay than to adjust myself in the driveway. Fortunately, my current shop takes care of that like they should.
I meant, when was the alignment machine last calibrated.
There is no reason for the steering wheel to be off center, even with a bent frame. Simply a matter of spinning both steering tie rods the same amount to get the steering wheel centered. Alignment will remain the same. I've fixed that myself on a few occasions, it taking much longer to get them to just pull it back into the bay than to adjust myself in the driveway. Fortunately, my current shop takes care of that like they should.
There is no reason for the steering wheel to be off center, even with a bent frame. Simply a matter of spinning both steering tie rods the same amount to get the steering wheel centered. Alignment will remain the same. I've fixed that myself on a few occasions, it taking much longer to get them to just pull it back into the bay than to adjust myself in the driveway. Fortunately, my current shop takes care of that like they should.







