Need help on lowering car!!

[deziking]

Say I had a 2004 mazda 6 S 4 sport sedan.If I wanted to lower the about 3 to 4 inches down. What do I have to do? I know I have to remove the tires and the brake pads and the stuff I mean I can’t do this at home rite so I have to taked it to a dealer or some technision. I want to learn how to do this any one can help me please

thanx repliers

[freakray]

You have to remove the wheels, not just the tires.
You don't have to remove the brake pads, you have to remove the brakes.
This is something you can do at home.

If you're considering learning to be a mechanic/technician, maybe you should first learn the basics?

[curtis73]

You may need a couple special tools, but you should be able to do this at home no problem. I'm going to post this only so you can get an idea of what's involved... NOT as instructions how to do it. There are too many variables and I don't know specifics about your Mazda.

Your car has struts in the front. A strut is a do-it-all upper suspension piece. It contains the shock, spring, and it is what turns and holds the brakes, hub, and axle. Here is a remedial picture. The "towers" with the springs are the strut.



here is another remedial picture.



In both, you can see the lower control arm that attaches from the crossmember to the hub/spindle. It swings up and down with suspension travel. What you'll need to do first is remove the wheels. Most cars you don't need to remove the brakes unless they're in your way or would be hanging by the hose during your work.

There should be two big bolts securing the hub to the strut. With the car up in the air and on jackstands, you can remove those two bolts. The hub/spindle and brakes should just fall out of the way still attached to the lower control arm by the ball joint. Now, under the hood you can remove the three bolts that secure the strut to the tower. DON'T take the nut off the center. That is what holds the assembly together under spring pressure. Taking that off can have explosive and shin-breaking results.

The only real special tool you'll need is a spring compressor. It will hold the spring so you can take the strut apart and put the new spring on.

Assembly is the opposite.

Rears are usually easier since they often just require removing the shock which lets the suspension droop fully and the spring darn near falls out. Some cars have a strut rear as well but I'm not familiar with the suspension on your 6.

Problems you will encounter, and there are a few.

1) When you're done it will need an alignment, but you won't be able to. You will have drastically changed the camber and since the upper strut mount is fixed there is no way to adjust it. The two big bolts that hold the strut to the spindle/hub allow for minute adjustments on the order of 1/2 of a degree, but you will have altered it 2-4 degrees depending on how much you lower it. Aftermarket companies often make caster/camber adjustment plates for lowered strut cars, but I don't know if they make any for a 6. You don't technically need to correct it, but only if your modification is only for looks. You'll cut your tire life in about a 1/4 and handling will be incredibly unpredictable on street tires. Race cars often run 3 or so degrees of camber but their tires are designed to conform in the right ways to match. Wet road handling will go from a predictable slight understeer to a wild oscillation between power-on understeer to power-off oversteer. Random 360s are to be expected, but not always. It depends on so many factors, but leaving it with that much camber is not recommended. Other downsides include uneven bearing loads, wheels will be much easier to bend since you're suspending the weight of the car on the inner bead, and ride harshness will be maximized for the same reason.

2) When you do this type of lowering, often times you'll need new shocks. The new spring rate will require different valving in the shock. It will also have a completely different travel range and a stock shock might bottom out or not allow enough travel causing damage to the car or other components.

3) The stock geometry is rarely ideal, but altering the ride height in a way that alters the lower control arm position puts the geometry in a less than wise point. Its not just as easy as re-setting your camber, your camber curve will be adversely affected as it goes through its travel. Knowing this, most manufacturers of lowering springs stiffen them so much to prevent travel.

4) This one is not a big deal, but some of these bolts will require more than just a rachet set to remove and install. Some of them are BIG and require in excess of 120 ft-lbs of torque to install. If you or a friend has an impact wrench and an air compressor, it would be beneficial.

This is NOT intended as a manual on how to do it. I've had some experience with many American and Japanese strut FWD vehicles' suspension, but not yours personally. I just wanted to give you a heads up so you know if its something you want to try.