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We get this call regularly. The clutch kit arrived, the transmission is out, the McLeod flywheel is in your hands, and the bolt holes will not line up with the crankshaft. Something must be wrong with the flywheel.
Almost never. 99.9% of the time it is just a matter of turning the flywheel. Here is why, and then how to choose the right one in the first place.
Why It Won't Line Up
McLeod provides full installation instructions with the flywheel, and they are worth reading. But this specific problem is not really an installation step, it is a misunderstanding about how the part is made.
The Indexed 8-Bolt Pattern
McLeod's 8-bolt flywheels are indexed to the crankshaft. The holes are placed in the same pattern as the rear of the modular crankshaft, and that pattern is not evenly spaced around the circle.
That is the whole explanation. Because the spacing is uneven, there is exactly one rotational position where all eight holes line up. Hold the flywheel at any other position and some holes will match while others sit off, which looks like a manufacturing defect and is not.
Rotate, check, rotate again. When it is right, every bolt starts by hand.
Choosing Your Flywheel
McLeod builds several flywheels for the modular 4.6L and 5.0L Coyote platforms. The popular ones are aluminum, steel, and lightened steel, all in the 8-bolt configuration that matches your modular crankshaft. They do different jobs.
| Flywheel | Best for | Why |
|---|---|---|
| Aluminum | Higher horsepower builds, supercharged or turbo | Least rotating mass, so the engine reaches high RPM fastest. CNC machined from 6061 T6 with a replaceable steel friction plate and hardened steel ring gear. |
| Lightened steel | Most street and strip builds | The middle ground. Lighter than standard steel without the drivability compromise of aluminum. If you are not sure, this is usually the answer. |
| Steel | Street, light race, and heavy cars with less power | Most rotating mass, which helps launch a heavy car that does not have the torque to overcome a light flywheel. Also the most forgiving in stop-and-go traffic. |
Replaceable steel friction plate
Hardened steel ring gear
For high-rpm boosted builds
Roughly 8 lbs lighter than standard steel
Best all-round choice for most builds
Helps launch a heavy car
Most forgiving in traffic
Order with the flywheel
Do not reuse old flywheel bolts
Any questions, give us a shout. We are one of McLeod's largest dealers and we are happy to help you get the right part the first time. #teamlethal
Frequently Asked Questions
Why won't my McLeod flywheel line up with the crankshaft?
Because the 8-bolt pattern is indexed to the crank and the holes are not evenly spaced. Rotate the flywheel until the patterns match and the bolts will install with no issue. This resolves it 99.9% of the time.
What does an indexed flywheel mean?
The bolt holes are placed to match the specific pattern on the rear of the modular crankshaft rather than being evenly spaced around the circle. That means there is only one rotational position where all eight line up.
Which McLeod flywheel should I buy?
Aluminum for high-horsepower boosted builds that rev fast. Lightened steel for most street and strip cars, which is the best all-round answer. Standard steel for street, light race, and heavier cars with less power.
What is the weight difference between steel and lightened steel?
About 8 lbs, which is enough to notice in how quickly the engine picks up revs.
Is an aluminum flywheel always better?
No. Less rotating mass means faster revs but also less inertia to launch a heavy car, and it can make smooth clutch modulation harder in traffic. Match it to your build rather than defaulting to lightest.
Can I reuse my old flywheel bolts?
Don't. Use new bolts. They hold a spinning mass to your crankshaft and it is not the place to save money.
Do I need to resurface my flywheel if I am reusing it?
Yes, and McLeod is specific about it: an 80 to 120 grit finish with a visible cross hatch. We cover that in the clutch break-in guide, along with why it matters for chatter.
Keep Reading
Rotate It, Don't Force It
Aluminum, steel or lightened steel, plus the bolts. One of McLeod's largest dealers, and happy to talk it through before you order.
