4HP-24 Automatic Transmission rattle

4HP-24 ZF:.

The transmission runs and shifts normally, with the torque converter lockup it makes a little jerk.

the previous owner had a little too low of oil in the gearbox.

now I have a rattle, but I don’t know exactly where it comes from.
when I switch to P and N it rattles very slightly when standing, when I accelerate a little it gets louder.

in D or R it is gone, even if I accelerate a little. can that come from the converter?
sounds like a grinding ballbearing .

thank you greetings

Possibly a crack in the flex plate?

Stojanov …

The first thing I would do is drain the transmission fluid, change the filter and refill. This may take care of your jerky gear changes.

As far as the vibration my guess would be the transmission mount has worn components. If you put the car on stands and crawl underneath push the end of the transmission up and then pull it down. there should be very little movement.

Both these jobs can easily be done with the car up on jack stands.

hello, and thanks for the answers,

which flexplate do you mean?
the one on the crankshaft with the ring gear for the starter?

I also have to check the storage of the entire gearbox …

Yes the one the starter uses.

oh that means gear down. or is there an opening to examine? down over the grille?

There is a rubber plug that allows access to the torque convertor bolts which you may be able to view a portion on the flex plate, its located on the starter side of the engine.

I was under the Hat.

there are two holes to access the flexplate.
once up next to the starter.
and once in the direction of the oil pan.

Flexplate is ok all screws tight.

but I think the catalytic converter is defective or loose …
I think that this is what makes the noise.
In addition, the bearing block / support of the gearbox is very spongy and can be lifted 30mm upwards …

Stojan …

The engine/transmission assembly is mounted to the car in three places. The two front motor mounts and the rear transmission support assembly.

If your referring to the rear assembly as the “block/support” and as you say that it’s very spongy and can be pushed up over 1 inch (30mm) then that very well may be your problem. There should be almost no play when you push up or pull down.
Screen Shot 2020-10-03 at 9.53.08 AM
This is a diagram of your transmission rear support. The parts that you will need to replace are the two springs (#4 and #11) and the foam donut (#7). You should be able to purchase everything for around $100. Normally the spring caps (#10 and #3) don’t need replacing.

Also if the safety strap (#19) dosen’t have the cover around it and it comes in contact with the springs it creates a lot of rattling.

Hihello, thanks for this drawing. may I know where you got this from? I’ve already looked at SNG … but everything just doesn’t come with the bearing block

Stojan …
Here’s the website to find all the parts for your car …

For the tranny mount go to “engine” and then go to “engine and gearbox mounting” that will give you the parts and the part numbers.

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Top thank you very much