Changing an Air Bag on a Discovery 2 fitted with SLS suspension.
This is one of those jobs that honestly take longer to get your tools out of the shed than to actually do…
Tools needed:
10mm spanner
Pliers
A 20p coin
The Standard Disco Jack, on a block or house brick
A small trolley jack
A plant sprayer with soapy water
AXLE STANDS
I didn’t use axle stands, I therefore do not recommend this method, Always use them!
… so don’t follow these instructions, you may get crushed by your own car and blame me, this is for information only!
The new air bag:
The Turret for the retaining clip:
First Chock the car, loosen the wheel nut, and remove the cover from the compressor (under the passenger seat) with a penny.
Next, support the chassis rail with a jack,
Then jack the axle, just enough to get the wheel off.
To expose the airbag (chassis needs waxoil!)
Open the boot, this de-activates the SLS computer from trying to counteract what you are about to do…
Gather your tools… a 10mm open spanner and pliers!
Slacken off the union where the pipe goes into the compressor to release pressure from the airbag
Remove the two retaining clips on the top, careful not to break them, they are the same as the clips that retain the handbrake cable.
Squeeze as much air out of the bag as you can
Use your 10mm spanner to undo the union
Remove the old airbag and clean up the bottom bracket bayonet
Twist new airbag into position, reattach pipe and then clips
Tighten up the union at the compressor
Close the boot, open the drivers window, check gearbox for neutral and run engine for a couple of seconds by reaching inside the window, this will put a touch of air in the bag, you may have to fool the sensor by jacking up the axle (so the computer thinks it’s low on that side) stop the engine and check that the bag has inflated properly, squarley and is properly seated.
Once you are happy, run the engine for a minute or so to put as much pressure in the bag as possible. And Very slowly lower the jack supporting the chassis.
Spray the union with soapy water to test for a leaking pipe, do the same at the compressor end.
Fit the wheel, remove the jack and chock, job done, go do the other side
Don’t be cheap, safety first: REPLACE AIR BAGS IN PAIRS !