I just bought it as a 2005 BMW 645Ci. No problem is when ...


I just bought it as a 2005 BMW 645Ci. No problem is when I get over 80 to 90 miles an hour the car starts making a click click click click click click sound that sounds like it's coming more from the rear or maybe the undercarriag...

I just bought it as a 2005 BMW 645Ci. No problem is when I get over 80 to 90 miles an hour the car starts making a click click click click click click sound that sounds like it's coming more from the rear or maybe the undercarriage. Mechanic's Assistant: Where exactly do you think the noise is coming from? And how long has this been going on? It sounds like it's coming more from the back but my boyfriend thinks that maybe the undercarriage to be loose and I just bought the car less than 5 days ago Mechanic's Assistant: What is the model of your '05 BMW? 645Ci Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far? Depends how serious of the problem is it when it be me fixing to be my boyfriend but no I haven't tried anything Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? That's okay for right now we can start with that

Automotive Expert
Good Afternoon, my name is \*\*\*\*\* \*\*\*\*\* ill be helping you, so sorry to hear about the issues here on the BMW, i know how frustrating it can be to deal with strange noises on a vehicle we have recently purchased. Now just so im clear does the noise change as you get faster or its the same once it starts? also have your been able to get any of the rear end components inspected already?

I haven't tried to go back to that then that when the noise when the noise starts I usually just slow down and I haven't had anything inspected on itI will say that the clicking once I let my foot off the gas and the RPMs go down the clicking stopthe other day when I went to go and put the car in Reverse this big cloud of like black smoke came out of the muffler
Automotive Expert
okay thank you, \*\*\*\*\* \*\*\*\*\* few things in the rear that can cause these symptoms. most commonly the noise comes from the rear differential being low on fluid or having worn fluid. i would recommend we look into having the differential fluid inspected and checked for being the correct level and not showing any metal in the fluid that would indicate a damaged rear differential. other things to consider would be worn wheel bearings in the rear as well as worn rear axle shafts but these are less likely than it being related to the differential

The guy who I bought the car from said he had just had the [brakes](/topics-brake/) replaced recently but they are squeaky as hell and I'm wondering if maybe the two are connected
Automotive Expert
i dont think they will be, if the brakes were an issue the noise would be present at all speeds and RPMs

Ok so do I need to have all my fluids checked in change is what you're saying
Automotive Expert
well related to your clicking noise from the rear it would be a differential fluid issue specifically.

At least to start with
Automotive Expert
correct

Okay thank youOkay thank you I will look into that would I be able to contact you again for other issues or if the problem is still going on after I get that looked into
Automotive Expert
not for other issues im afraid, its against site policy. you can contact me again about this specific problem

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