Example being the tone shift in the last third of Dhalgren. Not looking for horror itself because the genre is full of hack frauds.
:/
i haven't read dhalgren so i'm not sure i fully understand the tone you're looking for, but i would say that jg ballard novels have a creepy/unnerving dimension that never really delves into horror territory.
Kafka ofc
Some Borges maybe
>>8679726
Roadside Picnic
White Noise by Don Delillo.
>>8679726
it was kind of creepy how the protagonist kept running into filthy bikers who wanted to expose themselves.
>>8680339
sush
>>8680041
Good choice
The trial