Is anyone interested in the science and engineering of steering?

[Old School Life]

I have pulled out my college books that address steering, suspension angles, the effect each has on the other, the effects of improper toe, how caster and camber impact toe, how toe can cause shimmy (not loose, but shimmy) and how and why changing tires and wheels can change {wandering") - this is all from SAE (likely no one has heard of those folks) and another American Engineer group.
I thought about a write up using examples from the books, some of their diagrams and such and keeps it to the level that would be handy for those changing wheels and tires or having very specific problems.
It wouldn't be any sort of "DON'T DO IT!" thing but would be more for -"if you decide to to this, here is what you may run into and here's how to resolve it". (all I care about is successes)
It will take some time to put together as I'd be pulling from books as well as other resources I have - factory manuals, professional journals and all and I'd try to trim it to useful stuff, not stuff no one would ever use or need.
If there's interest, I'll write it up as I had considered doing this for another forum - I operate and administer a large car forum and write up electrical how-to's quite a bit and have done a little in steering and suspension but most of that is aimed at people LOWERING vehicles drastically.

For example, I have info on some of the causes of shimmy (that's not been addressed elsewhere as far as I know) as well as why taller tires can cause wandering - and how wheel offset can solve wandering,.
I can also explain why it's generally not possible to change the "caster spread" on a solid axle...... and what it takes to change caster and how caster and camber impact the NEED for toe - each in opposite ways, and which one causes the wheels to turn in and which causes them to turn out.

If there is no interest, fine - tell me to go to hell no one cares - I may save some hours, or I may do it anyway for the forum I operate. I'll back up everything via pictures, diagrams, and engineering information.,
You'll see a small fraction of what I had to know to get my degrees and certifications.

I have pulled out my college books that address steering, suspension angles, the effect each has on the other, the effects of improper toe, how caster and camber impact toe, how toe can cause shimmy (not loose, but shimmy) and how and why changing tires and wheels can change {wandering") - this is all from SAE (likely no one has heard of those folks) and another American Engineer group.
I thought about a write up using examples from the books, some of their diagrams and such and keeps it to the level that would be handy for those changing wheels and tires or having very specific problems.
It wouldn't be any sort of "DON'T DO IT!" thing but would be more for -"if you decide to to this, here is what you may run into and here's how to resolve it". (all I care about is successes)
It will take some time to put together as I'd be pulling from books as well as other resources I have - factory manuals, professional journals and all and I'd try to trim it to useful stuff, not stuff no one would ever use or need.
If there's interest, I'll write it up as I had considered doing this for another forum - I operate and administer a large car forum and write up electrical how-to's quite a bit and have done a little in steering and suspension but most of that is aimed at people LOWERING vehicles drastically.

For example, I have info on some of the causes of shimmy (that's not been addressed elsewhere as far as I know) as well as why taller tires can cause wandering - and how wheel offset can solve wandering,.
I can also explain why it's generally not possible to change the "caster spread" on a solid axle...... and what it takes to change caster and how caster and camber impact the NEED for toe - each in opposite ways, and which one causes the wheels to turn in and which causes them to turn out.

If there is no interest, fine - tell me to go to hell no one cares - I may save some hours, or I may do it anyway for the forum I operate. I'll back up everything via pictures, diagrams, and engineering information.,
You'll see a small fraction of what I had to know to get my degrees and certifications.

Bill, Thank you for taking the time for reporting on this topic. Due to family obligations, I am finally able to re-enter the world of a lifted vehicle. With the vast amount of changes over the years in suspension tech, the information you are posting will help make my decisions on installing the right lift on my JT and possibly correct any issues that may occur. As we all know, this isn't a cheap hobby and I want to make the most informed decisions possible. Looking forward to more postings.

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[5JeepsAz]

Hey is this the thread about science & engineering of steering? If so, I'm interested.

 

[Smess]

I'm trying to convey college level information, some from the engineers that designed this stuff and we get this?
Come on - this is NOT a discussion. Jeeps are not unique. Other vehicles have used the same or similar designs over the years.

There was a comment about software and how if there was a software issue everyone would have it. WRONG. More on that later......

So many here act like I need caster and toe explained - I actually HAVE taught the concepts. My high school instructor and a college professor both relied on me to help others in the classes. There are some Jeep specifics I am getting familiar with - the specific lay of the control arms or links on the front axle, their angles at curb height, what's welded where and so on, but the general principals apply to ALL 4 wheel vehicles, no exceptions.

My credentials -
IQ tested north of 130 - I banter with Mensa members now and then. (thus my lack of social skills - )
Started doing power equipment and cars at age 14-15. I had my own shop (and business cards) at 16 and I still have a copy of the newspaper article about that.
I did not have to take the first two automotive courses in HS because I had my own shop and "passed out of the courses" by explaining how a C6 transmission hydraulic circuits operated and the power flow in every gear as well as all of the circuits in a Holley 4bbl carb. I also won a bet with the teacher and he had to pay by buying the steel and welding me up a test bench - I still have it.
State champion Plymouth Troubleshooting contest - aced the test (perfect score) fasted time to judging in the practical, hands-on part with only one deduction. That record was never broken, they ended the contest a few years later due to MOPAR and money issues.
I completed HS requirements in 3 years instead of 4 - but stuck around to graduate with the class by joining VICA (and working in a former AMC shop afternoons) and taking advanced math classes (I didn't have to take the college math then)

College degree in automotive. Made the dean's list with a 4.0 GPA.
I came from a blue-collar family - my father was the wage earner, UAW, in a factory. (He became a UAW local president for a while) so there wasn't money to pay for my college - so I worked after classes doing - yeah, FRONT END ALIGNMENTS and brakes and tires and so on.
I got to use my training hands-on and dealt almost every day for hours with caster, toe, camber, included angle, SAI, point of intersection, scrub radius, etc. (guys, I know what caster is, how it's set, toe, how it works, etc.)

Out of college I applied for a job - the service manager was working on a car and having trouble getting rid of a weird miss. We chatted, he said if I could resolve the miss - I had a job. I read the scope, checked a few other things and came up with the solution in about 10 minutes. I was hired.
Manager of the biggest Jeep dealership in Iowa heard of my reputation by then and called me (at work, on my lunch break) and offered me the job of service manager. I turned it down. My boss then was excellent and I loved the work - I was more hands-on than paper and management. By then people were bringing in cars, trucks, Jeeps, yes, Jeeps, even small tractors and requesting that I be the tech to work on them.
Life changes - boss sold the shop, the corporation was stripping benefits and people left in droves.
I moved on - ran my own shop up on the farm I moved to and operated. Skid loaders, straight trucks, 4x4s and vehicles of all sorts. I got into computers during slow times.
I went on to Principal Financial Group where I resolved major endpoint security issues, did troubleshooting of network and endpoints and was eventually put in charge of several servers and desktop security software. I found an obscure bug in a corporate security software and worked with the developers at Symantec to duplicate and resolve the issue. Only a few companies in the world saw the issue - we were among them. They changed the code and I alpha tested it. They named the modification after me.
I was called in on a conference call with the US Navy, GM and others when a major viral threat was found and helped develop protections.
I moved on to Compressor Controls Corp where I designed the computers that were the interfaces for their then new Series IV turbo-compressor controllers. I also developed the environmental test battery, the image for the computers and worked with Young Micro Systems where the system boards for the computers came from. My first review my boss asked me what I though I should get as a raise - I said how about 10%. I got it.
I also resolved an obscure network issue involving log-ins to the Netware servers. I worked with Novell engineers and found the solution. I went up to upper management with my solution because my then boss refused to accept my ideas. Upper management gave me the green light and I restructured the network over a weekend - they said I could have anyone in the company help me. Monday morning everything was fine, all issues, including other weird issues, were gone. Weeks before they had paid big money to hire professionals to come in with sniffers to try to resolve the issue and could never find it. I used my methods and resolved it.
CCC was bought out by Roper, so I moved on - to government. I was promoted faster than anyone had been at that time.
I jumped past two levels up to ITS4 and was given charge of network security and become a network admin. After the network admin retired, I was then in charge of the entire state - 34 offices, 24 servers, 350 computers, LAN, WAN, mobile devices and more.
My wife and I sold a business and I used some of the money to build my shop and started automotive work again.
I retired from government and now do restorations and auto electric in my shop, including nickel and zinc plating, wiring harness design, diagnostics, etc.

Not new to computers, software or anything automotive having worked in the field for over 45 years.

Someone commented that if there was a software/firmware issues - well that just cannot be or all people would experience the same. No, that's not how software and computers work. You CAN have software that acts badly under specific circumstances and on specific electronics. At CCC, there were times when they had to specific NO SUBSTITUTIONS on certain components because, say they spec'd a Motorola IC but couldn't get it, so they went TI - same specs, they were direct replacements. They found no, the software behaved slightly differently and that the very slight differences in the way the TI worked under certain conditions caused trouble. I also found similar in the computers I came up with for their interfaces - if you put the video card in the slot next to the power supply, then the com ports, then ethernet and so on, it was fine, but swap the video and com ports and it would fail at certain times. TIMING. The electronic circuits appeared to act like water lines - and if one got a signal an extremely small fraction before the other -crash.
Watch Microsoft updates and patches - do ALL people have the same results?
Why would an Apple iOS update work fine on this iPhone but crash at a certain spot on another of the same model?
Jane's phone crashed at this screen after the update, John's did not. Same phone, same update. So yes, there can be software/firmware "bugs" that impact one but not another. (and an update may be specific to a rev of hardware)
That's why these companies want as much testing on as many different platforms under as many different conditions as possible.
I am not saying this IS software or not - just saying you cannot say it's not possible.
But I started this thread to share and convey facts, not shade-tree stuff read out on the web repeated enough times that it became true - because hundreds of people are saying it. That doesn't make it true.

It looks like I should give up trying to get valid real info out there because there will always be someone who knows better and will dispute it. I'd bet some even argue with doctors and electronic engineers.

I love this topic!!!!

I love when the alignment guy tells the Jeep owner that he can only adjust toe because its a solid axle.

I love when they install steering stabilizers and talk out the 1lb to tire pressure being the problem, and on and on and on.

Let me let you in a little secret jack, when you lift (lie said above) the axle goes towards the drivers side and rolls back wards which increases caster. 2007 and on Wranglers do not like a lot of caster, it actually creates depth wobble. When you lift more than 2.5 inches or more you should check alignment, JL's are more forgiving than JK's.

When the caster is 0 or very low then the steering wheel does not re-coil, you have to turn it back it wont even go itself.

So you start with the alignment and work backwards to the stabalizer that you dont need is last. I had a 2 dr with 5.5 inches of lift and I could create death wobble with the caster if I wanted to. There is a reason that AEV stopped selling the 4.5 inch lift for the 2 dr. The spring perches had to be moved and re-welded and most guys were too cheap or lazy to align so there were constant problems. Since the new steering box I have checked alignment on every JL and Glad I have had and all but one the alignment was out of spec from day one. Mostly toe, but caster on a Wrangler, learn it, live it, love it because it is a crucial part of the recipe especially on a lifted one.

 

[just_another_guy]

The long, unsolicited explanation of your high IQ and career accomplishments in unrelated fields says a lot about your intentions here. I think you already know that people want information on steering, and a good guide doesn't need the author to convince people he knows what he's talking about. You should have just written the guide and posted it rather than asking people to beg for it.

 

[it_trailblzr]

Maybe when you`re done, you should forward it to the Jeep engineers?

 

[Wheelin98TJ]

For credentials, I’d like to see pics of custom steering setups you have built.

 

[Joe Dillard]

For credentials, I’d like to see pics of custom steering setups you have built.

I sometimes enjoy seeing other folks' work too, especially if it's up to snuff/high standards without compromise.

 

[CaptNkllm]

Killed this thread.. Just let the guy post and see what he had to say... Guess not.. ego's roar!!

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