Can a drive shaft be repaired or does it always have to be replaced? You might think that your vehicle's engine and gearbox are the dream team (and they are), but if the torque can't be sent to the wheels, it’s game over. That’s why your drive shafts are very important indeed.
Is my drive shaft broken?
A drive shaft can snap or the splines can shear off, or you may even bend one if you hit something particularly unforgiving.
Here are symptoms of a failing drive shaft:
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Juddering – especially when you're accelerating.
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Vibration – through the steering wheel or seats. Sometimes known as a death wobble!
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Clunks – you'll notice this straight away.
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Clicking – especially when making a hard turn.
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Squeaks – a sure sign that there's no grease in the rubber gaiters.
If any of the above broken drive shaft symptoms occur, don't panic. In extreme situations you won't be able to continue driving, but replacing a drive shaft is actually a simple task that a home mechanic can undertake without too much trepidation. It’s just a case of being thorough, being safe, and of course, having your trusty
Haynes Manual to hand.
Replacing drive shaft, step-by-step
This is a basic explanation of the procedure on a typical front-wheel-drive vehicle.
Your Haynes Manual goes into full detail for your model.
1) Crack the hubs
The first job of drive shaft replacement involves removing the split pin from the hub nut, then cracking the hub nut off so it’s loose. Don’t take it all the way off though. It will be a big nut, approximately 30mm, so you’ll need the right socket. And you’ll need a lot of effort because they can be torqued to over 250Nm.
2) Jack up the car
Get the vehicle jacked up and on axle stands. The stands are not only for safety reasons here, you also need the wheels to be in the air – ramps won’t be any use here.
3) Wheels and brakes
Take the wheels off, put them under the car for safety and then start on the brakes. You’re going to need to remove the caliper, but you won’t need to disconnect the brake line. Use some sturdy cable ties or metal wire to suspend the caliper so there is no weight/tension on the brake hose
4) Hubs
Now you can free off and remove the hub nut completely. At this stage, you may also want to remove the brake disc – you don’t always have to, but it takes 20 seconds and makes for better access.
5) Lower ball joint
Undo the nut onto the lower ball joint and then with the aid of a ball joint splitter, break the hub assembly and the lower arm apart. You should now be able to pull the hub away from the driveshaft, freeing the outermost end. In some cases (and this is where your Haynes Manual comes in) you may need to remove the anti-roll bar.
6) Gearbox end
The end of the shaft of the goes into the gearbox will either slide right out, or it will need some gentle persuasion due it being held in by a circlip. Consult your manual before yanking it too much and breaking it.
7) Now go in reverse
To fit the new drive shaft, just follow the above steps in reverse. Can't get the driveshaft back in? After making sure the splines are correctly lined up, tapping it with a rubber mallet should persuade it to install correctly. Job done! Make sure you tighten the hub nuts up to the manufacturer's specified torque, which you'll find in your
Haynes Manual.
How long should a drive shaft last?
A drive shaft isn't replaced as part of a service – even a major service. This means there is no set interval for when they should be changed. Every car is different. The key to drive shaft longevity is preventative maintenance as well as just generally looking after them.
If you look after your drive shafts, they can last the lifetime of the car. It's only when you ignore the information below that they can become a problem.
The main shaft of the driveshaft unit is just a bar of metal, and as such is pretty robust. The only way this fails is if it’s damaged, or if rust is allowed to eat it away. As such, there is no harm in getting under your car with a wire brush, clean up the shaft and give it a new coat of rustproof paint. This will extend the life no end.
Other than that, there are two main points of failure, they are:
Drive shaft splined ends
Both ends of the drive shaft have a splined input piece. It is these splines that allow the driveshaft to be acted upon by the gearbox, while at the other end they allow the shaft to act on the wheel/hub, delivering power.
Normally, these spines are pretty hardy. However, if the car is driven hard, this can damage them. Also, if the car is modified to produce more power, it can be too much for the stock splines and can strip them from the shaft.
The most common issue is at the hub/wheel end. If the car has to have any work done that involves taking the hub off – so suspension work, a new wheel bearing, that kind of thing – if the hub isn’t fitted correctly, it can damage the splines.
Drive shaft CV joint
Drives hafts have a constant velocity joint at either end to allow the shaft to move with the suspension and steering of the car. These joints are packed with grease to keep them happy.
To keep all that grease in place, you have a CV boot, a rubber cover that flexes with the movement of the shaft. If this cover splits or comes adrift, dirt can get into the grease.
When that happens, the dirt grinds against the metal of the joint, eventually breaking it. New boots cost around $20 each, which is a small price to pay when you consider that new driveshafts cost hundreds of dollars to replace.
