2001 P38 AIR SUSPENSION PROBLEMS

Hi, i've just joined the forum.
This is my first Range Rover, bought in December last year, all looked in great condition.
Garage gave it a full 73000 miles service, or so i thought, garage owner drives an 04 Range Rover said he knows all about them, came back running lumpy, they had broken an ht lead, back to garage, changed all 8 ht leads. Came back now only doing 13mpg, also a rumbling noise from front. Took it back, they lifted the car on 4 points to check the wheel bearings, they said they had to remove a couple of fuses to get wheels to spin independently, they now seem to think it's the front diff, but wouldn't confirm unless i got Jaguar Land Rover dealer to put it on a rolling road. I brought the car home, next morning the suspension was flat to the floor. Had a look on the forum and ran car with door open for 10 mins, then shut door and suspension lifted to normal. Turned engine off 20 minutes later the rear suspension flat, the front still up., Overnight the front went down.
My question is could the garage have caused the problem and is there a simple fix?
Thanks in advance ossy11.

Hi
First of all welcome to Landyzone
Second of all i would seriously consider not taking your vehicle back to that garage. There is a good chance that someone on here lives near you and would maybe able to offer you some proper knowledgeable help and advice.
Stick with it mate and someone on here should be able to help you

Hi @ossy11
Welcome to the madness of green-oval.
Post your stuff in the vehicle specific sub-forum to get swiftest replies.
Lovely bunch on here, but also got some sharp-tongues so unless you have a thick-skin & broad shoulders avoid "Anything Goes" section till you have the measure of it.
Everything can be fixed. Eventually.

Thanks for the welcome guys
There is a beautiful R Reg 4.6 just around the corner from me and the owner seems to spend a lot of time doing bits and bobs, maybe i'll give him a knock.