The car was stopped at a light and when I stepped the gas it revved and made a little "kachunk" sound and "Gearbox Fault" came up on the dash and so now it wont kick into gear. It moves fine in neutral and reverse still works just fine. It's been shifting clunkily for a little while and now this happens. The car has about 83,000 miles. I am brand new to this site and I'm looking for some knowledge on what exactly the problem might be. I'd be happy to give more info about the situation if this doesn't explain enough.

 

The A-drum failed. A very common problem and you can see many years of threads if you just do a search.

 

It might be drum failure or low fluid
Get obd codes first
At least do filter and fluid change before you go further
MANN for filter and get zf5hp fluid or liqui moly 1200atf it's equal to lt71141 fluid 60$ for 5 quart on Amazon
If that didn't help then replacing the transmission is better
Get low mileage transmission from trusted seller
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