If your original PTO clutch is marked Warner 5218-388, Warner 5218-221, Ferris 5105090YP, or Ferris 5100084SM, you may notice that aftermarket catalogs often route these numbers to the same replacement clutch family.
This guide explains how the 5218-388 and 5218-221 clutch paths relate, what specs to verify, which OEM numbers are commonly grouped together, and which similar Warner clutches should not be confused with this replacement path.
Quick Answer: Are Warner 5218-388 and 5218-221 the Same Replacement Path?
Yes, Warner 5218-388 and Warner 5218-221 are commonly routed to the same physical replacement clutch family for select Ferris, Snapper Pro, Simplicity, and Briggs & Stratton commercial mower applications.
The same replacement path is also commonly associated with OEM numbers such as 5105090YP, 5105090, 5100084SM, 5100084S, and 5100084.
| Search Number | Common Replacement Path | Notes |
|---|---|---|
| Warner 5218-388 | 5218-388 / 5218-221 family | Commonly tied to Ferris 5105090YP and related commercial mower applications |
| Warner 5218-221 | 5218-221 / 5218-388 family | Commonly tied to 5100084SM and older Ferris / Snapper Pro paths |
| Ferris 5105090YP | Warner 5218-388 path | Modernized Ferris / Briggs & Stratton service number |
| Ferris 5100084SM | Warner 5218-221 / 5218-388 path | Older OEM path commonly superseded or consolidated in aftermarket catalogs |
Need the replacement clutch? See the 5218-388 PTO Clutch Replacement for Ferris & Snapper Pro.
Common OEM and Warner Cross References
The Warner 5218-388 / 5218-221 clutch family is commonly searched under several OEM and aftermarket number paths.
- Warner: 5218-388, 5218388, 5218-221, 5218221, 5218-134
- Ferris: 5105090YP, 5105090, 5100084SM, 5100084S, 5100084
- Snapper Pro: 5105090YP, 5105090, 5100084SM, 5100084S, 5100084
- Simplicity: 5105090YP, 5105090, 5100084SM, 5100084S, 5100084
- Briggs & Stratton: 5105090YP, 5105090
Because these numbers may appear in different service manuals, parts diagrams, or aftermarket catalogs, the safest method is to match your original clutch number first and then confirm the physical specs.
Key Specs to Verify
This clutch family is generally identified by the following physical and electrical characteristics:
| Specification | 5218-388 / 5218-221 Path |
|---|---|
| Crankshaft Bore | 1-1/8 inch |
| Pulley Diameter | Approximately 6.54 inches |
| Belt Width | Commonly used with 5/8-inch commercial deck belt applications |
| Rotation | CCW from pulley side |
| Voltage | 12V electric PTO clutch |
| Torque Class | Commercial 200 ft-lb clutch path |
| Connector Style | Integral connector style; jumper harness may be required depending on mower setup |
Important: Match the OEM part number or manufacturer part number on your original clutch whenever possible. Then confirm bore size, pulley diameter, rotation, and connector style before ordering. If you are relying on model information alone and cannot confirm the original clutch number, contact support before purchasing.
Common Equipment Applications
The Warner 5218-388 / 5218-221 clutch path is most often associated with select commercial mower platforms from Ferris, Snapper Pro, Simplicity, and related Briggs & Stratton commercial equipment families.
Ferris Applications
- Ferris IS Series: select IS1500Z, IS1500ZX, IS2000Z, IS2100Z, IS2500Z, and IS3100Z applications
- Ferris ISX Series: select ISX800 and ISX2200 applications
- Ferris SRS Series: select SRS Z2 stand-on mower applications
- Ferris FW Series: select FW35 and FW45 walk-behind applications
- Ferris ProCut / Outfront: select Procut S, F50XT, F150XT, and F200XT applications
Snapper Pro Applications
- Snapper Pro S-Series: select S50XT, S75X, S125XT, S150X, and S200XT applications
- Snapper Pro SW Series: select SW30 commercial walk-behind applications
Simplicity Applications
- Simplicity Citation XT: select commercial Citation XT applications
- Simplicity Cobalt: select commercial Cobalt zero-turn applications
Model fitment note: Ferris, Snapper Pro, and Simplicity mower models can vary by serial number, engine package, deck size, wiring setup, and production configuration. Use the model list as a fitment clue only. The original clutch number and physical specs should be the final confirmation.
Why Connector Style Matters
The Warner 5218-388 / 5218-221 clutch path may use an integral connector molded into the clutch housing instead of a long attached wire lead. Depending on your mower chassis and the replacement clutch supplier, a separate jumper harness or adapter lead may be required.
Before replacing the clutch, inspect the original connector, jumper wire, and mower-side harness. If the jumper harness is melted, brittle, corroded, or missing, the clutch may not connect correctly until the wiring is repaired or replaced.
Secure all wiring away from belts, pulleys, exhaust heat, and moving parts during installation.
Similar Warner Clutches to Avoid Confusing
The Warner 5218 and 5219 families include many clutches that look similar online but are not interchangeable. Do not assume that another Warner clutch will fit just because the number starts with 5218.
| Clutch Number | Why It Looks Similar | Key Difference | Risk |
|---|---|---|---|
| 5218-388 / 5218-221 | Correct replacement family for this guide | 1-1/8 inch bore, approx. 6.54-inch pulley, CCW rotation | Correct path when your original number and specs match |
| 5218-207 | Same 5218 commercial clutch family | Approx. 7.39-inch pulley | Pulley is too large for this Ferris / Snapper path |
| 5218-213 | Same 1-1/8 inch bore and similar pulley size | CW rotation | Wrong rotation can damage the clutch braking system |
| 5218-253 | Same 1-1/8 inch bore and CCW rotation | Approx. 7.25-inch pulley | Dixie Chopper-style path, not this Ferris / Snapper path |
| 5219 Series | Similar visual housing style | Usually 1-inch bore and lower torque class | Will not fit a 1-1/8 inch commercial crankshaft |
Warning: Do not order by appearance alone. Bore size, pulley diameter, rotation, connector style, and anti-rotation setup must match the original clutch path.
Before Ordering a Replacement
Before ordering a Warner 5218-388 or 5218-221 PTO clutch replacement, confirm:
- Your original clutch number matches 5218-388, 5218-221, 5218-134, 5105090YP, 5105090, 5100084SM, 5100084S, or 5100084
- The crankshaft bore is 1-1/8 inch
- The pulley diameter is approximately 6.54 inches
- The rotation is CCW from the pulley side
- The belt width and pulley profile match your mower deck belt
- The connector and jumper harness setup match your mower wiring
- The anti-rotation bracket or D-drive setup aligns correctly
- Your mower model, serial number, deck size, and engine package support this clutch path
If the original clutch number is unreadable, use your mower model and serial number to check an official parts diagram before ordering.
Recommended Replacement
If your original clutch number or parts diagram confirms the Warner 5218-388, Warner 5218-221, Ferris 5105090YP, or Ferris 5100084SM path, use the product page below:
Shop the 5218-388 PTO Clutch Replacement for Ferris & Snapper Pro
Common Symptoms of a Failing PTO Clutch
- Blades will not engage when the PTO switch is activated
- PTO clutch clicks but the mower deck does not start
- Deck engagement slips under load
- Blades engage cold but stop after the mower heats up
- Fuse blows when the PTO is engaged
- Burning smell near the clutch or belt area
- Grinding, rattling, or bearing noise near the clutch
- Visible heat damage, wobble, or bearing play
Before replacing the clutch, also check the PTO switch, battery voltage, fuse, ground, wiring connector, jumper harness, deck belt routing, spindle drag, idler pulleys, and belt condition.
Installation Note
New electric PTO clutches may require a proper burnishing procedure after installation. Burnishing helps seat the friction surfaces so the clutch can develop full holding power under load.
After installation, cycle the clutch on and off at moderate engine speed with no cutting load. Avoid immediately engaging the mower deck at full throttle in heavy grass before the clutch has been properly seated.
For removal tips, wiring checks, torque guidance, and burnishing steps, read the PTO Clutch Installation Guide before installing.
FAQ
Are Warner 5218-388 and 5218-221 the same clutch?
They are commonly routed to the same aftermarket replacement clutch family for select Ferris, Snapper Pro, Simplicity, and Briggs & Stratton commercial mower applications. Always match your original clutch number and confirm bore size, pulley diameter, rotation, and connector style before ordering.
Does 5218-388 replace Ferris 5105090YP?
Yes, Ferris 5105090YP and 5105090 are commonly associated with the Warner 5218-388 replacement path. Confirm your mower model, serial number, and original clutch number before ordering.
Does 5218-221 replace 5100084SM?
Yes, 5100084SM, 5100084S, and 5100084 are commonly routed to the Warner 5218-221 / 5218-388 replacement family.
What bore size does this clutch family use?
This clutch family uses a 1-1/8 inch crankshaft bore. It is not interchangeable with common 1-inch bore Warner 5219-series clutches.
What pulley size should I confirm?
This replacement path commonly uses an approximately 6.54-inch pulley. Do not substitute a similar-looking Warner clutch with a 7-inch pulley unless your original clutch number confirms that path.
Does this fit every Ferris or Snapper Pro mower?
No. Ferris and Snapper Pro use multiple PTO clutch paths depending on model, serial number, deck size, engine package, and wiring setup. Match the OEM or Warner number whenever possible.
What should I do if my original clutch number is unreadable?
Use your mower model and serial number to check an official parts diagram. If you are still unsure, contact support with photos of your clutch, connector, pulley, anti-rotation setup, mower ID tag, and deck belt path before ordering.