1717664 & 1717664SM PTO Clutch | Replaced by 01008434

April 22, 2026

Image of 1717664 PTO Clutch showing replaced by 01008434.

If your original PTO clutch is stamped 1717664 or 1717664SM, the correct current replacement is 01008434. You may also see it listed as 01008434P. In this clutch family, those numbers point to the same physical replacement path.

This replacement question comes up often because 1717664 and 1717664SM appear different at first glance. However, they are not different clutch assemblies. 1717664 is the base OEM number, while 1717664SM is the packaged service version used through Simplicity, Snapper, and Ferris replacement channels.

That means the SM suffix typically signifies service-market or service packaging, not a different pulley size, different bore, or different operating design. For fitment purposes, 1717664 and 1717664SM are treated as the same physical PTO clutch family, both replaced by 01008434.

1717664 and 1717664SM Replaced by 01008434

The simplest way to think about it is this:

1717664 = base OEM clutch number
1717664SM = service-packaged version of the same OEM number
01008434 = current replacement number
01008434P = packaged service version of the same replacement family

If your mower parts list, old clutch, or dealer paperwork references 1717664 or 1717664SM, the replacement number you want to land on is 01008434.

What the SM Suffix Means

The SM suffix does not normally indicate a different clutch design. Instead, it usually identifies a part sold through a service or dealer replacement channel. The core mechanical unit remains the same unless the manufacturer specifically publishes a design revision, which is not the case with this replacement path.

So if you are comparing 1717664 to 1717664SM, the important takeaway is that the suffix reflects how the part was cataloged or packaged, not that it became a different physical PTO clutch.

This is the same reason you may also encounter 01008434P on the replacement side. The suffix changes the catalog presentation, but not the fitment family.

Core Specs That Stay the Same

What matters most is that this replacement family keeps the same core fitment profile used across these applications:

1-inch crankshaft bore
Approximately 5.35-inch pulley diameter slight variance up to a quarter inch is common for multi-fit aftermarket replacement clutches
CCW rotation from the pulley side
Electric PTO clutch design verify height if possible and visually compare with the old unit to further confirm compatibility before installation
Operating range up to 3600 RPM
Approximate torque rating of 120 FT-LBS

Related OEM Cross-Reference Numbers in This Family

Although this page focuses on 1717664 and 1717664SM, the same PTO clutch family also appears under several other OEM numbers across multiple mower brands.

MTD / Cub Cadet / Craftsman: 01008434, 01008434P, 1008434, 759-05064
Simplicity / Snapper / Ferris: 5023100, 5023100SM, 1717664, 1717664SM, 1720532, 1757359, 1757359YP
Toro / Wheel Horse: 124833, 539124833
Additional interchange numbers: 7029232, 51110100, 35016, 33386

If you started with 1717664, or any part number listed above, the correct replacement is 01008434.

Common Simplicity, Snapper, and Ferris Applications

This replacement family is commonly associated with older Simplicity, Snapper, and Ferris mower platforms using 44-inch to 54-inch deck systems and a 1-inch bore electric PTO clutch setup.

Simplicity: 2750, ZT2300, ZT1842, ZT21546, selected Cobalt Series models
Snapper: selected SZT series applications
Ferris: HydroCut walk-behind models including 5900111, 5900543, 5900544, 5900545, 5900546

This model list is a helpful starting point, but the most reliable fitment check is still matching the OEM number stamped on the original clutch.

How to Verify the Correct Replacement

Before ordering, confirm the original clutch matches this family:

Match the stamped OEM number on the clutch housing
Confirm 1-inch bore
Confirm an approximate 5.35-inch pulley diameter
Confirm CCW rotation from the pulley side
Compare the wiring lead and connector style

If those details line up, 01008434 is the correct replacement path.

Do Not Confuse It with Similar-Looking Clutches

One of the easiest mistakes is choosing a clutch that looks similar but uses a different pulley diameter or OEM family. A clutch may bolt on and still create belt slip, weak blade speed, squeal, or poor deck performance.

This is especially important when comparing older multi-fit clutch families. Always verify the original OEM number first, then confirm bore and pulley diameter before ordering.

Common Symptoms of a Failed 1717664 or 1717664SM PTO Clutch

Blades will not engage
Deck engagement is intermittent
Clutch clicks but the belt does not drive properly
Blades slow down or stop in heavier grass
Bearing noise during startup or shutdown
Heat buildup or burnt smell near the clutch area

FAQ

Is 1717664SM actually different from 1717664?

No. The SM suffix indicates a service-packaged version of the same clutch, not a different physical assembly.

Why does my replacement search show 01008434 instead of 1717664?

Because replacement catalogs often roll older OEM numbers into a newer multi-fit aftermarket number. In this case, both 1717664 and 1717664SM route to 01008434.

What is the best way to verify this clutch before I order?

Match the OEM number stamped on the original clutch, then verify the 1-inch bore, approximately 5.35-inch pulley diameter, and CCW rotation from the pulley side. A quick visual comparison with the old unit is also smart.