Thread: D4 SDV6 vibration

Happy to report that my MY13 does not show the vibration the loaner car did. Very smooth and quiet.

Picking up on this old thread, was the closest ive found in my search here.

198,000km, Im getting a noticeable vibration at idle with the 6spd in gear, foot on brake.

Shift to N or P and all is smooth as silk. Vibration dissapears as soon as accelerating and nothing noticeable at normal hwy cruising speeds, or driving along normally. Tacho needle is rock solid steady, so no torque converter slip suspected.

No error codes (yet).

My thoughts are either transfer case or transmission. Have replaced fluids Sept 18 (about 25000-30000 km ago), rebuilt transmission valve body with new solenoids etc at that time too, full flush and running penrite BMV in transmission and royal purple syncromax in the transfer case.

I have read that front or rear prop shafts can also lose dynamic balance, is this something i should be looking at?

Originally Posted by Eric SDV6SE

198,000km, Im getting a noticeable vibration at idle with the 6spd in gear, foot on brake

If it's only happening when the car is not moving then it can't be anything past the torque converter as its all stationary. more likely to be something like an engine mount or something resonating.

What happens if you up the revs a little bit? Reason being if it was a resonation it'd change in character as the frequency moved.

I was going to say the same myself Brad. If at idle not moving you’ve eliminated the whole drive train.
Similar for me though. At idle, foot on brake, I get a sort of hum and noticeable change in sound from the engine that goes away above idle. If I find out what it is I’ll let you know as it might be similar

Car not moving, in gear = vibration felt. Not a hum but a definite vibration.
Shift into neutral = no vibration

Not checked engine mounts yet, and not checked if apparent when cold.

No clunks when dropping into gear, transmission temps all ok, idle steady at 715rpm.

Originally Posted by Eric SDV6SE

Car not moving, in gear = vibration felt. Not a hum but a definite vibration.
Shift into neutral = no vibration

Not checked engine mounts yet, and not checked if apparent when cold.

No clunks when dropping into gear, transmission temps all ok, idle steady at 715rpm.

You should be getting error codes if either of the Active Engine Mounts are faulty.

Originally Posted by DieselLSE

You should be getting error codes if either of the Active Engine Mounts are faulty.

Thats what i thought, as they run off the vacuum system.

The fact it does it when in gear tells me its transmission / drive train related

Originally Posted by Eric SDV6SE

Thats what i thought, as theby run off the vacuum system.

The fact it does it when in gear tells me its transmission / drive train related

Except the transmission and drive train isn't moving. It literally stops at the torque converter. The body rotates and the stator and output shaft doesn't until you take your foot off the brake and let the car move. Rotation stops there. How could it possibly be the drive train?

Having the car in drive just causes extra load on the engine making it vibrate a bit more. The torque converter is acting as a hydraulic brake dissipating the energy as heat into the fluid. Having it in park or neutral lets the torque converter, input shaft and bits of the gearbox rotate but with no load on the engine.