Spec 11-12 Ford Mustang 3.7L Aluminum Flywheel
If your 2011 or 2012 Mustang V6 manual is getting a new clutch, the flywheel is the part to decide on next. A heat-checked or glazed factory flywheel can make even a brand-new clutch chatter, and the stock part is heavy. SPEC SF37A is an aluminum flywheel for the 3.7L Ti-VCT V6 that gives the new clutch a fresh friction surface and lets the engine rev up and drop between shifts more quickly.
The flywheel bolts to the crankshaft, carries the starter ring gear and provides the surface the clutch disc clamps against. Cutting rotating mass means the engine gains and loses rpm faster, which makes rev-matched downshifts easier and sharpens response on a road course or autocross. SPEC sells tuned billet flywheels and says each is recommended based on how a given car reacts to changes in rotating mass. The trade-off with any lighter flywheel is a little more care needed pulling away from a stop and, on some cars, more gear rattle at idle.
SPEC lists SF37A for two setups on the 3.7L: SPEC performance kits with the V8 dowel pattern for use with SPEC flywheels, and SPEC performance kits with the original pressure plate dowel pattern for use with OE or SPEC flywheels. In other words, it is designed to pair with a SPEC 3.7L clutch, so plan the flywheel and clutch together.
With the gearbox out, inspect the flywheel face under good light and check it with a straightedge. Hot spots and cracks mean replace, not resurface. If the car is still together, do a slip test in a high gear at low rpm before deciding whether the whole clutch is due; our slipping diagnosis guide covers how, and this flare versus slip guide helps rule out other causes.
Our listing covers the 2011-2012 Ford Mustang with the 3.7L V6 and a manual transmission. SPEC's own catalog lists SF37A for the 3.7L V6 Mustang from 2011 through 2017, used with SPEC performance clutch kits. It does not fit the 5.0L GT or the 2.3L EcoBoost. Confirm your car is a 3.7L manual and match the part number SF37A. If you are unsure which pressure plate dowel pattern your clutch uses, send us the year and VIN with the clutch part number before ordering.
Pricing the full job? See our repair cost guide.
| Brand | SPEC |
| Part number | SF37A |
| Fits | Spec 11-12 Ford Mustang 3.7L Aluminum Flywheel |
| Vehicle fitment | Ford Mustang (2011-2012) |
| Type | Flywheels |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
SPEC lists SF37A for use with SPEC performance clutch kits for the 3.7L, in either the V8 dowel pattern or the original pressure plate dowel pattern. Plan to pair it with a SPEC clutch rather than the factory one.
Our listing is written for 2011-2012. SPEC's catalog lists SF37A for 3.7L Mustangs from 2011 through 2017. Send us your year and VIN if you have a later car and we will confirm.
No. SF37A is for the 3.7L V6 only. The 5.0L GT and 2.3L EcoBoost use different flywheels.
It revs more freely, so pulling away takes a bit more care at first, and some cars show more gear rattle at idle. Most drivers adapt within a few days.
Yes. Use new bolts with thread locker and torque them in a cross pattern to the specification in SPEC's instructions.
