Believe it or not, I'm looking out for you. The fact that I think these wheels and tires are ugly is irrelevant. I also think body piercings, tattoos, and purple hair are disgusting but they don't affect me or other drivers. (You'll notice these things are all done by children who haven't matured yet to the point of thinking for themselves, so they have to copy what they see). I also believe car manufacturers are secretly trying to build the world's ugliest cars to prove to each other that there are suckers out there who will still buy them, but again, that doesn't affect me as long as I am still not required to own one. What you want to do CAN affect other drivers but it can also affect you negatively in ways you don't understand, and that's what I'm trying to warn you about.
Every mechanic has training in liability issues and we are held to MUCH higher standards than doctors. Doctors just bury their mistakes. There are some bad doctors but the profession is held in great esteem. There are a few bad mechanics and because of that we are all considered part of a corrupt organization.
No reputable mechanic will lower your vehicle for you. Why is that? Every reputable mechanic knows what can result in them sitting in a courtroom and they take steps to avoid that. If you know better, by all means go right ahead and reduce the handling of the vehicle below the best that could be designed in. Degrade the brake system so stopping distances are increased and the anti-lock system will not react properly. Besides the increased danger you pose to other drivers, you are putting yourself at greatly increased risk of being found partially at fault for a crash you didn't cause. You obviously haven't lived long enough to have seen the many ways a simple decision to modify your vehicle can affect the rest of your life. There are many people who sail through life and never have a problem or end up in court, but there are just as many who do create easily-avoided problems for themselves. And when YOU are the one answering the lawyer's questions, you can be sure no one is going care if you are a do-it-yourselfer or a professional.
I get no satisfaction out of saying "I told you so". That is for arrogant people. I am anything but arrogant. I am meek, quiet, insecure, and easily intimidated, ... And I know how to stay out of trouble and how to keep you out of trouble. You go right ahead and modify your van since you're smarter than the vehicle designers, lawyers, and judges, but let me suggest you first sit in on a court case and watch how a lawyer can twist the facts and kick common sense out the window. If you still want to cobble a perfectly fine vehicle to copy a silly fad, at least you will be informed when you do so.
In the meantime, here are some of the questions going through my mind when students ask about lowering or jacking up a vehicle.
1. The control arms will sit at different geometric angles. What affect will that have on the rubber bushings and why? What simple step will void that rapid deterioration? What can I do to avoid the same problem with those bushings every year?
2. Being a front-wheel-drive vehicle, the engineers designed in a split-diagonal brake system. What does that mean? If half of the system springs a leak, what prevents a serious brake pull to one side when applying the brakes? How has "scrub radius" been modified compared to rear-wheel-drive vehicles to offset that brake pull so I can stop in a straight line and not lose control?
3. What happens to tire wear when the ride height is changed? Wheels are aligned statically, meaning the vehicle is standing still on a hoist. Two inter-related angles are set to the specifications that were found to provide the longest tire life and best handling. Sometimes they are a trade-off and you have to sacrifice one to get more of the other. Once that static alignment is set as the starting point, tire wear is greatly affected by the geometry of the suspension parts that let the wheels go up and down over bumps. The tires tip in and out on top as they go up and down. Why does that tipping increase when the geometry is wrong? Why does that make the handling feel "busy"? Why do my arms feel tired after driving this way for less than an hour?
4. Why do minivans and some trucks use a height-sensing proportioning valve and cars don't? Hint: it's in the brake system. How does that change the braking system when the rear of the van is lowered by only one inch?
When you can answer all of those questions, you will be informed enough to decide if the risk is worth it. Keep in mind that if you were my employee at an auto repair shop, you would get one verbal and one written warning to not park a modified vehicle in my employee parking area. After the third offense you would be packing your tool box and on your way to find a new job. There is no way I would risk the reputation of my business by having people think we condone these modifications.
Tuesday, May 3rd, 2011 AT 8:28 PM