I have a 2010 N52 with the ZF 6hp19.

When I start the car in the morning (and its 50 degrees or lower), I put the car in reverse and hear a "tink" sound when it goes into reverse.

If the car is warm and has been driven a few miles and I put the car in reverse there is no "tink" sound.

What is tinking?

 

Could it be the guibo going bad or could be a fluid issue.

 

The car has 55,000 miles on it.

Doesn't the guibo go bad around 100,000 miles?

I change the LifeGuard 6 transmission oil every year. I've changed it 5 time already.

It only makes a tink sound when I put it in reverse when the engine is cold.

In never makes a tink sound when I put it in drive.

If it was the guido wouldn't it tink when I put it in drive?

I'm going out on a limb. When I put it in reverse and it tinks, isn't that the reverse gear engaging with a drive shaft?

 

Yes it is engaging with the shaft. Usually they do go out around 100k but you also have to take age into account. When putting it in reverse the shaft may be hitting the guide which points to a dry rotted flex disc or balance shaft. It's worth a try to push on the shaft to see if there's play.

 

Did you try to put it in reverse then drive then reverse a bunch of times in a row?

If so, was it [consistently] reproducible?

 

I'll give that a try and see if it continues to tink.

Let's say after a few shifts back and forth from reverse to drive that it doesn't tink anymore when it goes into reverse.

What does that tell us at that point?

 

I'd get under and visually check the U joints. Removing a zillion screws is the hardest part.
Our 535 clunks at startup but that's a weird trans thing that doesn't hurt anything. Oddly, the 530 doesn't make a noise.

 

When I check the U joints should I physically be able to feel play (when I counter rotate the joint)?

 

Yes you will

 

Update:

The tink noise that I'm hearing in the transmission only occurs at start up when the car is put in Reverse.

If I put it in Drive there is no tink noise.

When the U joints are worn they should 'tink' in both Reverse and Drive, but it only tinks in reverse.

Why wouldn't the tink noise have something to do with the reverse gear engaging in a cold transmission?

Once the car warms up and I put it in reverse there is NO tink.