Flywheel and flexplate bolts run 45 to 85 ft·lbs, always in a star sequence, and many are single-use. Values by engine family plus the retaining rules.
Short answer: most flywheel bolts fall between 45 and 85 ft·lbs (61–115 N·m), tightened in a star sequence in two or three passes. GM LS is 74 ft·lbs, small-block Chevy 60 ft·lbs, Honda 76 ft·lbs, Subaru 51 ft·lbs and Ford modular 59 ft·lbs. Many are single-use, and most call for thread locker.
| Engine family | ft·lbs | N·m | Note |
|---|---|---|---|
| GM LS / LT V8 | 74 | 100 | Single use, replace bolts |
| Chevrolet small-block (Gen I) | 60 | 81 | Reusable, thread locker |
| Chevrolet big-block | 65 | 88 | Reusable, thread locker |
| Ford Windsor 302 / 351 | 75–85 | 102–115 | Reusable, thread locker |
| Ford modular 4.6 / 5.4 | 59 | 80 | Single use |
| Honda B / K series | 76 | 103 | Reusable, thread locker |
| Toyota 4-cylinder | 65–80 | 88–108 | Varies by engine |
| Subaru EJ / FA / FB | 51 | 69 | Reusable |
| Volkswagen / Audi TSI | 44 + 90° | 60 + 90° | Stretch bolt, single use |
| BMW inline-six | 77 | 105 | Single use |
Tighten in a star pattern. Number the bolts around the flange and work across the circle, exactly as you would a wheel — 1, then the one roughly opposite, and so on. Going around in a circle cocks the flywheel on the crank flange.
Two or three passes. Snug everything, then bring the set to half torque, then to full. A flywheel is a large-diameter joint and will not sit flat if bolts are pulled up one at a time.
Clean the crank flange and bolt holes. Blind holes in the crank trap oil. Fluid trapped under a bolt gives a false torque reading and can crack the flange. Chase and blow out every hole.
Use thread locker only where specified. Where a manufacturer calls for it, use the grade it names. Where the bolts come with a pre-applied patch, do not add liquid locker — replace the bolts instead.
Lock the crank properly. Use a flywheel holding tool or a locking plate on the ring gear. Jamming a screwdriver into the teeth chips them and can slip at 70 ft·lbs.
A flywheel is a solid mass for a manual gearbox. It stores rotational energy and provides the clutch friction surface. Its bolts hold a heavy component that is also being loaded by clutch clamp force.
A flexplate is a thin disc for an automatic. It carries the ring gear and bolts to the torque converter, and is designed to flex axially as the converter expands under pressure. Flexplate-to-crank torque is often lower than a flywheel's, and the separate converter-to-flexplate bolts are lower again — commonly 20–45 ft·lbs.
Do not mix the two specs. The converter bolts are the ones that most often get the flywheel figure by mistake. Check which fastener the number in front of you belongs to.
Staged sequences and TTY bolts
Valvetrain fastener specs
Reference for a high-strength imperial bolt
Convert a metric service-manual figure
Most flywheel bolts take 45–85 ft·lbs (61–115 N·m). Common figures: GM LS 74 ft·lbs, small-block Chevy 60 ft·lbs, Honda B/K series 76 ft·lbs, Subaru 51 ft·lbs, Ford modular 59 ft·lbs. Tighten in a star sequence over two or three passes.
Some engines allow it; many do not. GM LS, Ford modular, BMW and VW/Audi flywheel bolts are single-use, and the VW/Audi type is a stretch bolt finished with a 90° angle. Older reusable bolts still need clean threads and fresh thread locker.
Usually yes, unless the bolts have a pre-applied locking patch — in which case fit new bolts rather than adding liquid locker to old ones. Use the grade the manufacturer specifies; a permanent-strength compound where a medium one was intended makes future removal very difficult.
In a star pattern across the circle, never around it, in two or three progressive passes. This pulls the flywheel down evenly onto the crank flange and keeps it running true.
A flexplate is the thin disc used with an automatic transmission. Its crank bolts are often torqued lower than a manual flywheel's, and the separate torque-converter-to-flexplate bolts are lower again, typically 20–45 ft·lbs. Confirm which fastener your figure refers to.