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5/8-18 UNF UNF bolt size
15/16 wrench
wrench size for 5/8-18 UNF UNF bolt
5/8-18 UNF UNF bolt — Automotive, aerospace, structural.
Full specification
| System | Imperial UNF (fine) |
| Nominal diameter | 0.625 in (15.88 mm) |
| Thread pitch | 18 TPI |
| Wrench size | 15/16 |
| Tap drill | 37/64 (14.7 mm) |
| Clearance hole | 21/32 |
| Common grade / class | Grade 5 |
| Typical torque | 210 Nm (154.9 ft·lb) |
🔧 Torque unit converter
Pre-filled with typical torque for 5/8-18 UNF (Grade 5).
About 5/8-18 UNF UNF bolts
Automotive, aerospace, structural.
UNF (Unified National Fine) thread has more threads per inch than UNC (coarse). 5/8-18 UNF has 18 threads per inch.
Fine threads provide better vibration resistance and finer adjustment, commonly used in automotive and aerospace applications.
Frequently asked questions
- What size wrench fits 5/8-18 UNF bolt?
- 5/8-18 UNF bolt uses a 15/16 wrench.
- What is the torque for 5/8-18 UNF bolt?
- Typical torque for 5/8-18 UNF UNF bolt in Grade 5 is about 210 Nm (154.9 ft·lb).
- What is UNF thread?
- UNF (Unified National Fine) thread has more threads per inch than UNC. 5/8-18 UNF has 18 TPI.