diff --git a/quantize_awq.py b/quantize_awq.py
index 53c1bfe..77032d7 100644
--- a/quantize_awq.py
+++ b/quantize_awq.py
@@ -13,9 +13,13 @@ from llmcompressor import oneshot
 MODEL = "/workspace/substrate-qwen36-27b-merged"
 OUTPUT = "/workspace/substrate-qwen36-27b-awq"
 CALIB_DATA = "/workspace/substrate_v5.jsonl"
+# Merged model was saved with transformers 5.5.0 which writes
+# tokenizer_class=TokenizersBackend — unknown to 4.57.6 in the quant venv.
+# Load tokenizer from original repo (has standard class name).
+TOKENIZER_SOURCE = "Qwen/Qwen3.6-27B"
 
 print("Loading tokenizer...")
-tokenizer = AutoTokenizer.from_pretrained(MODEL)
+tokenizer = AutoTokenizer.from_pretrained(TOKENIZER_SOURCE)
 
 print("Loading model...")
 model = AutoModelForCausalLM.from_pretrained(