Front End, Suspension, And Steering
The parts that make up your car's steering and suspension have seen the worst of the road - water, mud, snow, and salt. Then throw in age and lack of maintenance, and those old components need to be replaced before they become a safety issue.
Worn Front-End Parts
With time and neglect, front-end and suspension parts wear. These include inner and outer tie rods, and on rear wheel drive cars, idler arm, pitman arm, and center link.
Certain under-car components will wear out more quickly than others. For example, outer tie rods wear faster than inner tie rods. On rear wheel drive vehicles, lower ball joints wear out faster than upper ball joints. Some components will give you a sign before failing by leaking or squeaking.
Front End Suspension Repair
Most under-car components are usually unwilling to be removed easily. This is where it pays to work smart. Before you try removing those old parts, grab a can of WD-40 or a similar penetrating fluid and generously spray the parts to be removed. Let them soak for a long time (five minutes is NOT a long time). The longer it soaks, the better it works.
Before trying to loosen tie rod or ball joint nuts, take a wire brush and clean off the exposed threads first. Sometimes a gentle rap with a hammer helps loosen stuck parts.
When trying to remove old ball joints from the control arm, a Ball Joint Fork is invaluable.
Ripped And Torn Dust Boots
When ball joint or tie rod boots rip or tear, the grease ends up on your car's undercarriage, but worse, they wear out much faster. It starts as a creaking or clunking, then worsening to excessive play in the suspension and steering. If you catch the damaged boot early enough, you can simply remove the old boot and install a new one. But if you're not sure of a component's age, replace it for safety's sake.
Read: Replace Tie Rod Dust Boots
Classic Cars and Tires
In the interest of better handling and fuel economy, radial tires emerged in the late sixties, becoming standard on Corvettes in 1973, and most other American cars by 1974.
Read: Bias-ply vs Radial Tires
Read: Classic Care Tires
Front End Alignment
Uneven tire wear usually indicates a front-end alignment issue, which may be caused by worn suspension parts, such as lower control-arms and ball-joints.
Other symptoms of improper alignment include pulling left or right, wandering, scuffing, and dragging.
One of the five things I learned working at the tire shop was, unless you have a working experience with front ends, it's hard to understand the geometric principles of alignment.
Caution: Crawling underneath an unsupported car is dangerous. Make sure your vehicle is secure on jack stands before you work on it.