X5world - View Single Post

supersteve · #**117** 02-18-2008, 10:16 AM

Faccen1,

NBX's post answered most of your questions. That's a great link by the way. Thanks NBX.

The one I would like to address is the rattle on start up. It's not normal; but, it's ok.

The valves are what is rattling. After the engine shuts down if one (or more) of the valves are being held open by the position of the cam and the lifter for that valve leaks down it will rattle on start up. It is only bad if it doesn't stop within a few moments from start up.

My 01 X5 4.4 with 132000 miles does it occasionally. My brother's 740 4.4 with 240000+ miles does it also.

Does it sound bad? Yes
Is it doing damage? No
Can it be fixed? Yes
Is it worth the money and effort? No

These engines have 4 vavles per cylinder. Each has a lifter, times eight cylinders. That means 32 lifters. In order to find the correct lifters to change they must be pulled from the engine and put into a test rig to have them leak tested. Do you think most dealer mechanics will invest that much time??? No, they'll change all 32 lifters and hand you the bill.

Every time you hear that rattle on start up just think of all the money, frustration and time you saved by not chasing that ghost.