Speaking of trouble...
Lifting a vehicle is going to affect its handling. Most obviously, you're going to add height to the centre of gravity, which in turn is going to make the vehicle more prone to roll in corners. At the extreme, an already roll-happy SUV or truck will become even more likely to turn over in the event of an accident.
Similarly, just because you've lifted your truck, don't think you can instantly go off-road with it like a pro. If you're doing it for off-road functionality rather than just pose value, spend the extra cash and get a one-day off-road course. You'll have a blast and it will make you infinitely safer when you do take your vehicle off the beaten track.
It's also worth pointing out that putting larger wheels on simply to increase ground clearance can come with all its own problems including the legality of it, changes to the steering and suspension geometry and steering load. It's also a possibility on some types of 4WD vehicle that larger tyres and steering load can result in tearing the steering box off the chassis. Other things which tend to fail quicker when this is done are items like pitman arms, track rods, knuckle and ball joints - all of these get stressed beyond their normal design limits when you stuff massive tyres and wheels on a truck.
One other point to consider when doing this: if your speedometer is based on a mechanical link to the gearbox, your speedo will become so innacurate that it will basically be useless. You'll be driving at an indicated 30mph but could be doing 40mph if the tyres are big enough.
Just be warned.
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Lowering Kits
The opposite of lift kits - lowering kits. These are designed to (wait for it....) lower your car. Also at the other of the scale - lowering kits are almost exclusively used on cars, whereas lift kits are almost exclusively used on trucks and SUVs. (Having said that, the number of pimped-out low-rider trucks on the road does seem to be increasing by the day.) Lowering your car will similarly affect the handling, just like a lift kit. But again it's the opposite end of the spectrum - a lowered car will typically handle much better than factory suspension, and it will lower the centre of gravity, making it less likely to tip or roll in an accident. I'm a European, and as far as I'm concerned, if you're going for pose value, lowering your car is the quickest way to do it, hotly pursued by larger wheels and tyres to make the car appear even more ground-hugging.
Lowering kits typically consist of shorter, stiffer springs and gas shocks - often nitrogen-filled. Don't do it by halves. Get a matched kit from someone like Spax or Jamex. Matched kits have springs and shocks designed to work together. If you get shorter springs, your factory shocks will be under a lot of stress because they'll be operating a much shorter throw than they were designed for, and ultimately, they'll normally fail much quicker. Similarly, don't get shorter shocks and the cut the springs. Cutting the springs is the epitome of A Really Bad Idea. You're weaking the spring's structural integrity and the chances are that when you've finished a ham-fisted attempt at hacking off all 4 springs with a grinder, the result will be 4 springs all slightly different lengths.
There's something else worth mentioning here - do not try to disassemble a shock absorber. Ever. Those things are like little bombs, and unless you have all the right tools, you could easily loose a hand as the shock explodes into its component parts when you get that last twist off the collar. Please - just don't. I know your mate Guido might have told you it's a "sure fire" way to shorten the shock, but he's lying.
Matched lowering kits typically assume you're going for sportier handling, so a lot of times, you'll get a whole slew of new adjustments which you never had before. Spring height, rebound damping, compression damping etc. My recommendation is to leave everything as it is to start with. Right out of the box they're normally set up pretty well. The following renderings show an example "before and after" of a lowering kit fitted to a car:
Lowering kit questions.
What if I get shorter springs to lower the car? Will I need to adjust my caster and camber angles and/or my shock absorbers?
Generally the answer would be no for caster/camber angles. Most cars have a good 10-13cm (4-5 inches) movement in their suspension from the factory. As most of the lowering springs you can buy only lower by 2-7cm (1-3 inches), your suspension should still be well within it's designed operating limits. Therefore, caster and camber angles shouldn't need looking at.
What if I get shorter springs to lower the car? Will my tires rub on my arches?
They shouldn't unless you start messing about with wheel and tire sizes. Again, given that most suspension kits lower within the car's normal operating limits, there shouldn't be a problem. If there was, then every time you went over a big hump with standard suspension, the tires would rub. Rubbing against the arches will almost certainly only occur if you lower the car and widen the wheels.
Source: Car Bibles.com
