Land Rover Repair: 2004 Discovery SE7, rear driveshaft, drive shaft

Question
Hello
My 2004 Discovery SE7 has a humming noise. It is audible when you accelerate and becomes very loud at 55-60+mph. If you remove your foot from the accelerator, the noise disappears. So, to the layman, it sems like a drive train issue. There is no vibration issues at all. The same noise is also audible when you approach a stop sign seemingly when the lowest gear kicks in. The L/Rove dealership here in Fort Lauderdale have diagnosed it as a bad bearing in the front differential and want me to pay to replace the entire differential.
In order to pin-point the problem, should they have not removed the front drive shaft to see if the noise disappears hence eliminating the transfer case??
Last, if it is the front differential, can i simply remove the front driveshaft and just run it with the rear driveshaft only. I never have the need for 4 wheel drive here in Florida.
Thanks very much for your help...Holly

Answer
I must agree this does sound like a differential problem.  They do not need to remove the drive shaft to pinpoint the problem.  It can be diagnosed on the hoist with a stethoscope.  You can remove the front driveshaft if you have diff lock and you engage it.  I doubt you have diff lock, however, and I would not recommend this. Since this part does not frequently fail on this car, I would advise you to find a used differential, which should save you quite a bit of money.