A common MoT failure on both T4 and T5s is a split CV boot. For those who may not know, CV stands for constant velocity, and refers to the rotating joints found at either end of the axles. These are packed with grease, which is held in place (and dirt kept out) by a convoluted rubber boot. Once a boot splits, which they will all do at some point due to the rubber perishing, the all-important grease can escape from the joint and dirt and road debris can enter. This will cause rapid wear of the joint and, if this is allowed to continue, will soon damage the joint irreparably and you will have to replace the entire joint. However, if the damage is spotted soon enough, you can simply replace the rubber CV boot. Here’s how to replace a CV boot on a T4.
To do the job properly, you will need to raise the front of your Van up and support it securely on axle stands so that the wheels can both be taken off, allowing you full access to the front suspension and the driveshafts. The lower balljoint will need to be split, which can normally be done with a large hammer, but if not you will have to obtain a balljoint splitter, or a ‘pickle fork’, to complete the job.
On our Van, for peace of mind we replaced both the inner and outer CV boots on both sides as it’s cheap and easy to do with the driveshafts off the car, and if one has already split, the chances are the others won’t be far behind. Removing the inner CV joint from the shaft is the easiest option, and both boots can be fitted from that end.
When fitting the new CV boots, clean as much of the old grease out as possible and re-pack with the special grease supplied with the kit. Our kits came from a local motor factors, but you can buy them from most of the VW specialists who advertise in this magazine, or you may even find some bargains on the likes of eBay and other similar auction sites.
- TOOLS USED
To fit the correct clips to hold the CV boots in position you will need a pair of pliers as shown in the lead picture. As you won’t use these for any other job, you may not wish to buy them, so ask around and see if you can borrow a pair
- SKILL LEVEL
2/5 (5/5 being hard and 1/2 being easy)
- TIME TAKEN
1-2 hours per side
- COST DIY
CV boot kit £4.50 per joint
- COST PRO
Approx £55 (parts and labour)
We bought new inner and outer CV boot kits for less than a fiver each, and you can buy complete CV boot and joint kits for around £30. Avoid the universal kits though, and get the correct ones for your model of Van
How to replace a CV boot on a T4: Step 1
Before you can start you need to jack the front of your Van up and support it on axle stands so that you can remove the road wheels and gain access to the front suspension. Luckily, we had access to a lift making life much easier.
How to replace a CV boot on a T4: Step 2
Here you can see the state of one of our inner CV boots, which were split on both sides. Our outer ones were also badly worn, so we decided to change all four, which meant we had to remove the driveshafts.
How to replace a CV boot on a T4: Step 3
The driveshafts are fixed to the gearbox with a series of Torx bolts and you will need a 12mm Torx bit to fit these. Clean the heads out carefully and undo these one at a time, rotating the driveshaft to gain access to all of them.
How to replace a CV boot on a T4: Step 4
You will also need to disconnect the lower suspension arm from the swivel hub to allow the driveshafts to be withdrawn. To do this, the shock absorber needs to be disconnected. Clean the lower fixing point with a wire brush and coat with WD40 or a similar penetrating oil before trying to undo it.
How to replace a CV boot on a T4: Step 5
Next you will need to do the same with the lower balljoint. Use a 24mm socket or spanner to undo the nut once you have cleaned and lubricated it. Do not remove the nut just yet as you need to leave it on to protect the threads.
How to replace a CV boot on a T4: Step 6
If you have a balljoint splitter, now is the time to use it. If not, use a large hammer to hit the lower suspension arm. This should release the lower balljoint, which uses a taper pin. A couple of hard, swift hits with the hammer should suffice.
How to replace a CV boot on a T4: Step 7
The large driveshaft retaining bolt also needs to be removed. Have a friend stamp on the brakes to prevent the hub from rotating while you use a long breaker bar and a 27mm socket to undo the bolt. Again, do not remove it completely at this point.
How to replace a CV boot on a T4: Step 8
Before the bolt is removed give the head of the bolt a tap to release the driveshaft and then the bolt can be withdrawn. You will then need to remove the lower balljoint nut completely and lift the hub up whilst also pushing the lower arm down to release the taper balljoint.
How to replace a CV boot on a T4: Step 9
Once the balljoint is disconnected, you can release the driveshaft from the hub and then withdraw the shaft from the Van completely, ready for stripping down and replacing the CV boots.
How to replace a CV boot on a T4: Step 10
With the shaft off the Van and carefully supported, use a set of circlip pliers to remove the circlip from the end of the shaft. This will allow you to remove the inner CV joint and the old remains of the split CV boot.
How to replace a CV boot on a T4: Step 11
Lift off the CV joint and then slide off the remains of the CV boot. This is a messy job, so be sure to wear some protective gloves to keep the old grease away from your skin.
How to replace a CV boot on a T4: Step 12
There is a metal retaining clamp that attaches the CV boot to the joint. This will need to be prised off with a large screwdriver or similar, taking care not to damage the joint itself.
How to replace a CV boot on a T4: Step 13
The new CV boot comes already attached to the metal retaining ring so simply push it onto the driveshaft until it sits in the groove in the shaft. A small amount of WD40, or similar, will ease its passage.
How to replace a CV boot on a T4: Step 14
The new CV boot should come with a small packet of special grease, which should be applied directly to the CV joint. Clean out any old grease first and ensure that there is no dirt or road debris present as this will cause the joint to wear prematurely.
How to replace a CV boot on a T4: Step 15
The metal retaining plate is a snug fit over the CV joint so, once we had lined the holes up, we used some grips to bring the two together. Take care not to damage either part and ensure the boot is pressed on evenly all the way round.
How to replace a CV boot on a T4: Step 16
The final part is to fit the correct type of clip to the end of the rubber boot. This is important as it stops any grease escaping from the joint and any dirt or debris getting in. If you do not have the correct tool and cannot borrow one, take the shaft to your local garage as most will do it for you for a drink.
How to replace a CV boot on a T4: Step 17
Before fitting the shaft back onto the Van, replace the circlip. This prevents the shaft from coming away from the CV joint. Circlip pliers are needed here to do the job without damaging the circlip, or firing it across your garage and under some immovable object!
How to replace a CV boot on a T4: Step 18
Having replaced both the inner and outer CV boots, it’s now time to re-fit the driveshaft to the Van. Offer the shaft into position and then pull the hub out of the way so you can engage the end of the driveshaft into the front hub.
How to replace a CV boot on a T4: Step 19
With the shaft back in the hub, re-fit the lower balljoint. Push the lower arm down and lift the hub up to allow you to do this (you may find a second pair of hands useful for this step). Fully tighten the nut once fitted in place.
How to replace a CV boot on a T4: Step 20
The shock absorber can now be bolted back up to the lower suspension arm. Don’t forget the washer and tighten it up fully using a 21mm socket on one side and a similarly sized spanner on the other.
How to replace a CV boot on a T4: Step 21
Using your 12mm Torx bit you can now fit the bolts back into the end of the driveshaft flange. Once they are all fitted loosely, they need to be tightened fully using a torque wrench set to 80Nm. You will need someone to press the brake pedal while this is being done.
How to replace a CV boot on a T4: Step 22
With everything else tightened up, re-fit the centre hub bolt and tighten it with the torque wrench, this time set to 150Nm. Then turn it an extra 90 degrees. You may find it easier to do this when you have finished the procedure and the Van has its wheels on and is back on the ground.
How to replace a CV boot on a T4: Step 23
Finally, double check everything is secured properly and then re-fit the road wheels and lower your Van back to the ground. Repeat on the other side if necessary, then you should be ready for many more miles of trouble-free VW motoring.
For more technical guides on fixing problems or making modifications to your Volkswagen T4 or T5 Transporter, have a gander at our: VW Transporter technical guides