Self-Levelling Q. (very noisy fanbelt)

[genphreak]

Hello all,

Mum's '95 525i touring (an M50/5HP18 auto) has developed a very noisy serpentine belt.

It seems from the screaching noise that the belt is slipping (but only when the car is laden). It can happen (a little) unladen, ie when taking off from rest uphill (and especially when the engine accelerates).

Clearly when the rear suspension switch causes a load to the SLS pump, the belt is slipping. Do I just need to change the belt and belt tensioner, or is it likely to be something worse like the pump being worn out so unable to maintain the correct pressure?

In my limited (I've no pressure gauge) testing the LAD appears to work fine- but it does not sound good under a heavy load. The car is:

- in good condition and has done about 200,000km (180,000miles)
- not throwing up any Suspn Levelling warnings on the dash
- the ride height seems good
- after being parked at night the rear sags a bit and the fluid height in the reservoir rises a bit above the mesh.
- when we got the car earlier this year it was doing this and it had red fluid (perhaps 7.1 or a mixture of that and Dexron). I changed at least 1.4L of fluid- replaced with CHF 11 as I thought that all LAD was CHF11, so now its a bit purplish. However the Bently lists 7.1 as the OE fluid (I've no handbook). Section 330-11 of the Bently covers the system in detail.

The problem is she's going on holiday and I only have a day or two to fix it before she goes... so far, all I've been able to buy is a tensioner and fan belt. Any advice would be appreciated... although I have to say I'm not keen try an SLS delete a few days before they go... (let alone find the bits- it would take a week minimum to get the parts)

The holiday is only 2000km of driving, so if I could just reduce it till they get back, that'd be a good result.