Blade12r

I searched around a bit on the forum but didn't find much specific to my model with the same issue. Recently purchased a 2008 E63 with 94k on it...car is super clean, unfortunately on the test drive the noise did not come about. When I let off the gas after heavy acceleration there is a solid thud/clunk sound...just once. From what I found on the forums here it seems to be the motor mounts. Just looking for a little input as I need to drive the car from Portland to NorCal where it will live....There is no sound under normal acceleration, only when the pedal is to the floor pretty much and then let off. I'm on a time table and am not able to have it looked at before the trip...any and all input is greatly appreciated.

M3diesel

Just don't drive it aggressively and you'll be fine. The engine mounts have anchor bolts within the mount itself so it will not raise more than and inch or so. The real issue would be puncturing the upper radiator hose from the engine lifting up. Drive it calmly and you're good to go. Have a safe trip!

Strigoi

Both of my motor mounts were collapsed and recently replaced. I didn't have any weird noises or clunks because of them and it's seen plenty of full throttle pulls at varying speeds. You could just feel a bit more vibration in the car, especially at idle.

I think you have something else going on. When you check under the car, do you have any orange stains in that area? One of mine leaked out, the other was collapsed but didn't show any signs of leaking.

Motor mounts are also a bit labor intensive. The whole exhaust system needs to come out to do them. My roommate (works at an indy shop) did mine in about an hour and a half, I'd expect double that time in labor from a dealer.

This should not have to be done to swap motor mounts. Lame.

Blade12r

Thanks, This was pretty much the plan, you really have to stomp on it and let off quick to feel/hear the clunk...going to take it as easy as possible.

Blade12r

It's been raining here pretty hard since I got the car so haven't noticed any stains in the driveway...but today is clear so I will take a look, but also I think they went long before I got the car. It was the the previous owners third car and was rarely driven (under 300miles last year) and when it was it was by his wife with two kids usually in the car. So Even when it was driven it wasn't driven hard enough to notice the clunk. He offered to reimburse me for part of the cost of repairs....

After finding this clunk, and being more aware....there does seem to be more than usual vibration at idle, as well as on deceleration sometimes.

Are there any options for stronger motor mounts? Aftermarket? Or are the OEM the best/only option?

I was expecting that the labor would be anywhere between 2-5hrs even at the Indy....

M3diesel

Pop the hood and power brake it to see if the engine lifts up which is a sure sign of a broken drivers side engine mount. The passenger side mount only breaks if the drivers side was broken for a long time so there is a good chance the passenger side is fine. I would replace both anyway but breaking the passenger side is relatively uncommon. No aftermarket polyurethane so go with OEM.

Blade12r

thank you, this was on the list for today since it's the first rainless day after noticing the problem....

Blade12r

Power braked it, and the motor jumps about an inch or so on the drivers side....thanks for the help!

maxusa

I just diagnosed the same issue. Same symptoms (rough idle especially cold, cabin vibration, clunk on burst rev/acceleration). A local MB tech did the same test power brake engine visibly tried to jump out of the car on the driver's side. Quoted $530 parts + $1,007.18 labor. I can source genuine parts online $281, and wonder about DIY labor. Is it practical to undertake this job on jack stands/engine brace? Has anyone done it here? Written instructions, made a video?