The following write-up is applicable to 89-01 Swift/Metro/Cultus variants with bolt-on disc rotor type front hubs.
I had some buggered up threads on one of my front wheel studs, and I did not have time to remove the hub from the car and use the recommended method, which is using a shop press to remove and replace the stud.
There are a lot of folks on the interwebs that say that the best alternative to a shop press and hub removal is to use a BFH (Fig Hucking Bammer?) to simply hammer out the old stud and also to install a new stud. This alternative method seems violent to me, as the wheel bearing would also be subjected to damaging forces. Ditto for suggested methods using an air hammer to drive out the stud.
So I found a tool at Princess Auto ( Ball Joint Separator), which ironically is not usable on our cars for ball joints, but can be used as a mini press for wheel studs. A similar tool is offered by OTC, and a cheaper version at Harbor Freight.
I like pictures to narrate, so here goes:Edits completed Oct 5 2016
So, here is the bad stud that needs to be replaced on my 2000 Metro.
You will need some basic hand tools. The only item displayed here that may not be in your tool box, namely the impact driver. You should get one, since Suzuki likes using soft metal Philips head screws/bolts that are usually fastened too tight to easily remove with a normal screwdriver.
A quick strike of the impact driver with a hammer should loosen things nicely.
The brake caliper can be unbolted from the knuckle and then gently placed aside. I placed it on top of the steering tie rod so that it is supported but out of the way.
It helps if you mark things so that they can go back on in the same position.
The disc rotor can now come off. You can inspect the stud better and reposition the hub so you that have room to work.
Let's look at the back side of the hub.
Here is the tool we are going to use. I paid about $45 CDN. Harbor Freight has one for $19 USD and there's probably a Snap On version for a billion dollars lol.
Carefully position the tool on the hub making sure that the forces will only be applied to the old stud and that the tool arms are in good contact with the back side of the hub.
Here is a better view of the back.
As you tighten the big bolt of the tool, make sure the threads are lubricated with oil. It is a heavy duty bolt, but lubricant will make it last a long time, and reduce the torque you need to loosen the old stud. Spray some WD40 or similar onto the old stud where it passes through the hub. This will also reduce the pressing force needed to remove the old stud. The stud will make periodic popping noises as it is pressed out of the hub. Some people say to give the stud a tap with a hammer. I say NO to hammers during this procedure! This picture shows the old stud has been pressed out fully.
The new studs are just over a dollar, from the dealer. I would not buy aftermarket studs because they are universal design without detailed specs. For my 2000 Metro 3 cylinder hatchback, the front studs are 37 MM long in the front, and 34 mm long for the back brake studs.
The hub should have splines that are intact that you can still feel with your finger. If the splined surface feels really smooth, the hub may require replacement, as your new studs could spin when installed in the hub. Mine were okay, as you can see. (and I could feel, lol)
The tool has to be flipped around to press the new stud back onto the hub from behind. There are 2 pivot location holes for the press arm, and I had to use the lower pivot holes so that there is more travel available to press the new stud onto the hub.
The 2 big washers were needed to let the tool arms apply force square onto the new stud head. I did not want to press the stud in crooked..
When the stud is fully installed (seated) in the hub, the tool will no longer allow you to tighten its big pressing bolt. A visual inspection of the stud from both sides of the hub will verify that the stud is in full contact with the surface of the hub.
I will take a moment to summarize the reasons why hammers are a very bad idea for installing wheel studs onto hubs that are still on the car.
(1) using hammers to install studs can damage the wheel bearing. Yes, bearings take a lot of abuse from hitting potholes and curbs. But I don't drive that way, so why take a chance?
(2) Some people suggest after using a hammer to partially install the new stud, to then use a lug nut and some washers to fully pull the new stud into the hub. Sure you can do that, but accident recreation studies have shown that the torque required to fully seat a stud requires around 300% of factory torque, which will not only stretch the threads on your new stud, but do the same to your lug nuts.
(3) If you are unable to fully seat the new stud with a hammer and do not notice that fact, the clamping force for the new lug nut will not be correct even after you torque it to specs.. the stud can subsequently slide in and out of the hub. This may cause catastrophic stud shear failure as the other studs on the hub (assuming they are in good shape) would be subjected to potentially greater forces as your car corners, brakes, etc..
Time to reassemble everything. Use a torque wrench if you have one!
Wheel lug torque is very important. Suzukis/Metros are sensitive to improper torque and there are a lot of different factory recommended torque values. My car requires 45 ft. lbs.
A final comment on torque. If your lug nut threads or stud threads are stretched or damaged, torque values are pretty meaningless. My lug nuts can be hand threaded all the way to the wheel with little effort, but with enough slight resistence to indicate that the threads are not damaged.