futurerx06

Hello BMW E60 Members! I need your help if you know this! Appreciate it!

I went to BMW Maintenance for regular check up so they did a diagnostic test and this is what they recommended:

1) Need A/C and ALT Belts
2) Rear Differential Mount Fluid Leaking ---> he said if I do not change it, this could catch on fire so do it ASAP.

My questions are

1) Anyone know DYI - how to change A/C Belt and ALT Belt? can I buy A/C Belt online?

2) What is ALT Belt means? can I buy it online OEM?

3) What is Rear Differential Mount Fluid Leaking? How much you guys think it cost to fix it?


Thank you guys E60 members! Go Bimmer

Howitzer

Get a second opinion from another BMW shop.

futurerx06

should i show them the 1st BMW Shop diagnostic sheet print out?

JasonH

I'm talking here about the 530d but I bet the petrols are similar:

The A/C is the air conditioning compressor belt.
The ALT will be the massive belt that drives everything else - water pump, power steering, alternator etc.

Space is tight in there but pretty much jack the front up and remove the undertray to see the belts. Take a picture - you need to thread the belt back on the same way it was before.

You need to take the A/C belt off to do the other belt so it's common practice just to change both.

Get a spanner on the spring loaded tensioner. Take the pressure off the belt and slip the belt off - watch your fingers if you slip with the tensioner you could lose a finger. Then gently let go of the tensioner. Do the same for both belts.

The belts do age. You should be able to buy decent equivalents from a few sources.

Can't comment on the diff mount I'm afraid.

JasonH

You can see the belts at the front of the engine. Use a torch (flashlight) to see better. They're rubber and should look healthy, not brown, brittle, cracked or glazed.

futurerx06

Thanks Jason...your tips are helpfuL!