2004 X5 - questions and concerns

[puffjaon]

Hello all, I have been searching and reading before I asked this question as I have been hammered on other non-bmw sites.

As I said I have an 04 X5 4.4 and two things are concerning me, every once and I while it feels like one of my front tires goes out of balance and it gets worse when the brakes are applied. It may only last a few miles and then stops. So I put the car up last night to check all the suspension parts and nothing feels really lose. The one thing I notice is a bit lose are the thrust arms, by lose I can move them with my hands but no clunking or crazy lose. The other thing I noticed was the passenger tire (both we up and the car was on jack stands) did not spin as freely as the drivers side. I am going to take it to a very good mechanic but even he said that you tend to just start replacing stuff. Maybe time to trade it in on a new one?

The other thing I have noticed is that when the car is in park and on the car makes a whirring sound, to me it sounds like the fuel pump is making the sound.

Any way, thanks in advance and Happy New Year

[Weasel]

If the battery charge is low you can sometimes hear a whirring sound from under the hood from the load on the alternator, but usually don't hear the fuel pump unless the fuel level is low enough for the pump to not be submerged, which on a BMW means out of gas... so if you really do hear the fuel pump it may be on the way out.

For the coming and going balance problem, the thrust arms wouldn't cause a shaking but do exaggerate it when present. It could be the wheels out of balance, or it could in an axle shaft... though that is less likely. Best to have the wheel balance checked first as a good starting point.

[Quicksilver]

Are you sure that "whirring sound" isn't the rear air pump?
Every now and then I hear mine.

[Bill Valley]

Originally Posted by Weasel

If the battery charge is low you can sometimes hear a whirring sound from under the hood from the load on the alternator, but usually don't hear the fuel pump unless the fuel level is low enough for the pump to not be submerged, which on a BMW means out of gas... so if you really do hear the fuel pump it may be on the way out.

For the coming and going balance problem, the thrust arms wouldn't cause a shaking but do exaggerate it when present. It could be the wheels out of balance, or it could in an axle shaft... though that is less likely. Best to have the wheel balance checked first as a good starting point.

Agreed. Have you rotated tires recently? An out of balance rim is your most likely culprit.

[puffjaon]

If a tire was out of balance the sensation would not come and go, it would be constant. I just had my snow tires put one a few weeks ago and again 90% of the time the car drives fine and then sometimes I get the sensation the tires are out of balance. This morning in fact the car drives perfect. Last night not so good.

As for the battery, should I replace the battery then?

[Weasel]

Not unless that is the actual problem... that is just one of many possibilities. I wouldn't change any parts without confirming that is a/the problem.