[vilord]

My 6AT car occasionally has a hard downshift when rolling up a hill no load.
It also has a bit of driveline vibration under acceleration at about 40mph.
At 106k miles, I'm sure it needs a transmission fluid/filter change and flush.

Yesterday on my way home I gunned it down a little straightaway near my office, everything functioned as it should, but when I idled to a stop a mile or so later, everything was vibrating something fierce. Get up past idle and vibration is gone.
Can't be a u-joint, because I was stopped, but it felt similar.
Popped the hood and the vibration was coming from the back of the engine.
Worried I fucked something in the engine I decided that the best thing to do is to duck into whole foods and buy some dessert.

When I came back out and started it back up, vibration was gone.
Could this be something wrong with the torque converter? Or dirty fluid getting stuck in a TC fluid passage?

[NinetyEight740]

Check engine light come on? How do you see movement at rear of engine only?

[vilord]

No check engine light.

I can't see vibration, but I can feel it if I put my hand on the front vs the rear of the engine, and can also hear it.

[Moisture]

You need to service your transmission. I wouldnt suggest doing hard acceleration .

[tlow98]

sounds like a misfire that wasn't logged.

Also, change your fluid. That ZF box was supposed to have it at 60k.

[dsjr2006]

It could be lots of things, including a bad motor or trans mount.

[MineralweissIS]

Originally Posted by dsjr2006

It could be lots of things, including a bad motor or trans mount.

+1 check the condition of your mounts.

[nsjames]

Originally Posted by tlow98

sounds like a misfire that wasn't logged.

Also, change your fluid. That ZF box was supposed to have it at 60k.

if it's a 328 it's the GM, but they still recommend a 100K mile interval for fluid and filter under normal conditions.

it certainly cleared up any part throttle shudder that mine had at 101K miles.

I would service the transmission and not worry about it until it reappears, then diagnose it.

sounds like coil things to me.

[tlow98]

Originally Posted by nsjames

if it's a 328 it's the GM, but they still recommend a 100K mile interval for fluid and filter under normal conditions.

it certainly cleared up any part throttle shudder that mine had at 101K miles.

I would service the transmission and not worry about it until it reappears, then diagnose it.

sounds like coil things to me.

ah thought this was a turbo car! 07 328 - i don't recall if the zf box was still lingering then? I think the general rule of thumb was 325 = zf, 328 = gm

[vilord]

Sorry, didn't specify, this is the 2009 328xi, so 99.9% it has the GM. Glad to hear it has a 100k schedule.

I'll get the trans fluid changed this week, and see if it clears up. Thanks!