Engine Identification
Engine code letters are suffix of Engine Identification Number. Number is stamped in pad on front right side of cylinder block.
CHEVROLET & GMC
| Application |
Man. Trans. |
Auto. Trans. |
| 454" |
| |
Federal |
TRZ, TRT |
TRR, TRU, TRS, TRW, TRX |
| Calif. |
TRZ, TRT |
| High Altitude |
TRZ, TRT |
TRR, TRS, TRU, TRW, TRX |