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Front End Alignment Diagram Help Needed

XTrooper

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Hello, folks. Well, I put a new set of tires on my JL about a week ago and, to play it safe, got the front end alignment checked this morning. In the past, I always got a print-out with the alignment numbers labeled unlike the unlabeled sort of 3d diagram I received today. It has me a bit confused and I hope someone can decipher it for me. I think it is showing that the front camber is off, left and right, and I'm sure not what's going on with that left rear tire. I'd greatly appreciate it if someone could explain what is being shown here and if any of it is significant enough for me to worry about. Thank you! 👍
Jeep Wrangler JL Front End Alignment Diagram Help Needed jeep_jl_frt_alignment
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Hello, folks. Well, I put a new set of tires on my JL about a week ago and, to play it safe, got the front end alignment checked this morning. In the past, I always got a print-out with the alignment numbers labeled unlike the unlabeled sort of 3d diagram I received today. It has me a bit confused and I hope someone can decipher it for me. I think it is showing that the front camber is off, left and right, and I'm sure not what's going on with that left rear tire. I'd greatly appreciate it if someone could explain what is being shown here and if any of it is significant enough for me to worry about. Thank you! 👍
Jeep Wrangler JL Front End Alignment Diagram Help Needed jeep_jl_frt_alignment
Alignment looks good, no worries. On that type of read out when green and red is together that means your in spec , but leaning towards high or low end of spec. On these JLs you want caster to be solid red on the high end, lol. But no worries you’re good to go.
 
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Thank you very much, guys! I appreciate it! The mechanic didn't seem to be too concerned when I was talking to him, but it wasn't his $1400 worth of tires so why would he be?! 😉
 

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If it helps, there’s nothing you can adjust.
In stock form, that is true, but offset ball joints can be used to make caster and/or camber adjustments, if necessary. I'm glad to find out I don't need them.
 

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...I'm sure not what's going on with that left rear tire...
Camber readings can be adversely affected by unequal tire pressures which may cause the entire vehicle to lean in such a way that the measurements for camber misrepresent the actual dimensions of the vehicle's suspension components. This is not spoken of widely, probably because a significant number of people have adopted the belief that tire pressure does not affect alignment measurement, which is ok for some of the parameters like toe and caster, so it is not uncommon for alignment technicians to ignore tire pressure discrepancies and create reports with camber values that are not truly representative of the suspension.

Perhaps that is what happened in your instance?
 
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Camber readings can be adversely affected by unequal tire pressures which may cause the entire vehicle to lean in such a way that the measurements for camber misrepresent the actual dimensions of the vehicle's suspension components. This is not spoken of widely, probably because a significant number of people have adopted the belief that tire pressure does not affect alignment measurement, which is ok for some of the parameters like toe and caster, so it is not uncommon for alignment technicians to ignore tire pressure discrepancies and create reports with camber values that are not truly representative of the suspension.

Perhaps that is what happened in your instance?
Thanks for that information, Yellow Cake Kid. It's not something I would have thought of, but it is not what happened in this case. I am OCD and that applies to tire pressures! They are always within 3-4 psi maximum, usually less.
 

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Thanks for that information, Yellow Cake Kid. It's not something I would have thought of, but it is not what happened in this case. I am OCD and that applies to tire pressures! They are always within 3-4 psi maximum, usually less.
Tire pressures during an alignment check should be exactly equal. Exactly. No tolerance.
 
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Tire pressures during an alignment check should be exactly equal. Exactly. No tolerance.
I find it extremely difficult to believe that a 60 lb, E-rated, 10-ply tire could be physically altered at all by a gain or loss of 2-3 psi of air pressure, let alone enough to affect the results of an alignment check, particularly of the toe. I’d be very interested in knowing the source of this “exactly equal, no tolerance” assertion. Thanks!
 

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I find it extremely difficult to believe that a 60 lb, E-rated, 10-ply tire could be physically altered at all by a gain or loss of 2-3 psi of air pressure, let alone enough to affect the results of an alignment check, particularly of the toe. I’d be very interested in knowing the source of this “exactly equal, no tolerance” assertion. Thanks!
You are looking at fractions of a degree when it comes to alignment data. I hope by “60 pound” you mean the weight of the actual tire, which is irrelevant. The typical tire pressure on a Jeep is less than 40 psi. A 10% difference is significant.

Inflating tires to equal pressure is step one of the alignment procedure.
 

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@mwilk012 is correct. To give the most accurate alignment all things must be equal. That said I think the alignment on a solid axle vehicle, especially a Jeep is highly over rated and often obtained unnecessarily at times. Jeep in its stock form the only thing you can adjust is toe and straighten the steering wheel. Sure you can adjust caster and camber but you need to replace parts to do it, they’re not adjustable on the Jeep as is. Only time I get an alignment is when I do a complete lift that replaces all eight control arms even then I don’t need to do it but I like to see the caster and thrust angle read outs. Angle finder works to get it close , but there’s to many variables to get a precise reading........anyway, just my .02. Sorry for the novel.....I really need to stop posting during my morning coffee.....:facepalm:
 
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You are looking at fractions of a degree when it comes to alignment data. I hope by “60 pound” you mean the weight of the actual tire, which is irrelevant. The typical tire pressure on a Jeep is less than 40 psi. A 10% difference is significant.

Inflating tires to equal pressure is step one of the alignment procedure.
Yes, I was referring to the weight of the tire and, you're correct, it is irrelevant to the topic. What isn't irrelevant is that these tires have a maximum inflation pressure of 80 psi and are built for that kind of pressure. This fact, along with their relatively stiff 3-ply sidewalls, makes it highly doubtful a few pounds per square inch of pressure are going to make any difference.
I completely agree with you that inflating tires to equal pressure is a solid and prudent practice. I don't believe having the tire pressures exactly equal is necessary for every instance. However, I am pragmatic and know that it may be necessary in every single instance so, rest assured, I will adjustment my tire pressures to exactly the same psi the next time I have the alignment checked. Thank you for the information you provided and your persistence! :like:
 
 



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