Lock Nut

Enhance the performance of your heavy equipment with the Case Construction Lock Nut #88559. Designed for durability and reliability, this essential part ensures secure fastening, keeping your machinery running smoothly and efficiently on any job site.

Compatible equipment

This part fits CASE CRAWLER TRACTOR, CRAWLER DOZER, SERIES - CASE UNI-LOADER SKID STEER LOADER, CASE UNI-LOADER SKID STEER LOADER, BACKHOE, CASE SKID KING WHEEL LOADER, BACKHOE AND LOADER FOR 530CK TRACTORS, BACKHOE FOR W7, W9A, W9B, W10, BACKHOE AND LOADER, BACKHOE FOR 310G AND 450 CRAWLER, BACKHOE FOR 580CK, BACKHOE FOR W SERIES RIGID LOADERS, LOADER, BACKHOE FOR CRAWLER MODELS 750, 850, 1150, BACKHOE FOR 680CK TRACTOR, BACKHOES FOR CRAWLER MODELS 750, 850, 1150, SERIES A INTERNATIONAL LOADER TRACTOR, BACKHOE FOR 450, 450B, 850, 850B, AND W14, LOADER AND BACKHOE FOR 580CK SERIES B, CASE TRENCHER, CASE SKID STEER LOADER, SKID STEER - 410 NA BSN N7M480924, 410 EU BSN N7M468736, SKID STEER - SERIES 3, 410 NA ASN N7M480924, 410 EU ASN N7M468736, SKID STEER - 420NA BSN N7M466710, 420EU BSN N8M466713, SKID STEER - TIER 3, 420NA N7M466710, 420EU ASN N8M466713, COMPACT TRACK LOADER - BSN N7M455401, COMPACT TRACK LOADER - SERIES 3, ASN N7M455401, SKID STEER - SERIES 3, ASN 430 NA N7M479683, 430 EU N7M479546, SKID STEER BSN 430 NA N7M479683, 430 EU N7M479546, SKID STEER - BSN N7M425032, SKID STEER - TIER 3 , ASN N7M425032, SKID STEER - 440 NA BSN N8M474469, 440 EU BSN N8M407542, SKID STEER - SERIES 3, 440 NA ASN N8M474469, 440 EU ASN N8M407542, COMPACT TRACK LOADER - BSN N7M483467, COMPACT TRACK LOADER - SERIES 3, ASN N7M483467, SKID STEER - BSN N7M454787, SKID STEER - TIER 3 , ASN N7M454787, COMPACT TRACK LOADER - BSN N8M458846, COMPACT TRACK LOADER - TIER 3 , ASN N8M458846, SKID STEER, TIER 2, P.I.N. N7M458414 & PRIOR, SKID STEER, TIER 3, P.I.N. N7M464019 & AFTER, COMPACT TRACK LOADER - BSN N7M464019, COMPACT TRACK LOADER - SERIES 3 ASN N7M464019, SKID STEER - TIER 3 ASN N7M452623, SKID STEER BSN N7M452623, CASE CONSTRUCTION KING LOADER BACKHOE, WHEEL LOADER STD LINKAGE - STAGE V - 2025 UPDATES, WHEEL LOADER XT LINKAGE - STAGE V - 2025 UPDATES, WHEEL LOADER - STAGE V - TS - XT, WHEEL LOADER - STAGE V - TS - ZBAR, WHEEL LOADER - T4B - STD LINKAGE, WHEEL LOADER - T4B - XR LINKAGE, WHEEL LOADER - T4B - XT LINKAGE, LOADER LANDSCAPER, CASE CONSTRUCTION KING TRACTOR W/SHUTTLE TRANSMISSION, CASE CONSTRUCTION KING WHEEL TRACTOR W/HYDROSTATIC TRANSMISSION, CASE CONSTRUCTION KING LOADER BACKHOE - 4WD SUPPLEMENT, CASE CONSTRUCTION KING LOADER BACKHOE - TURBO SUPPLEMENT, SERIES 2 LOADER BACKHOE - ASN JJG0239360, CASE SUPER-D CONSTRUCTION KING LOADER BACKHOE, CASE SUPER-E CONSTRUCTION KING LOADER BACKHOE, CASE SUPER-K CONSTRUCTION KING LOADER BACKHOE, LOADER BACKHOE - BSN JJG0239361, TURBO LOADER BACKHOE, LOADER BACKHOE, SERIES 2 LOADER BACKHOE - ASN JJG0210575, CASE TERRATRAC GASOLINE CRAWLER TRACTOR, CASE WHEEL LOADER, CASE WHEEL LOADER TIER 3, WHEEL LOADER TIER3 ZBAR EC4 - BR, WHEEL LOADER TIER3 ZBAR EC4 FERTILIZER - BR, WHEEL LOADER TIER3 ZBAR EC4 SUGARCANE BAGASSE - BR, WHEEL LOADER TIER 3 NA/EU, MOTOR GRADER - ASN 020001, MOTOR GRADER TIER 2- BTW 020101-020187, CASE LONG TRACK CRAWLER TRACTOR, CASE TURBO TRENCHER, MOTOR GRADER - ASN 022001, MOTOR GRADER TIER 2 - ASN 022101, MOTOR GRADER - ASN N5AF04007, MOTOR GRADER - ASN 024001, MOTOR GRADER TIER 2 - BTW 024102-024129, MINOTAUR COMPACT DOZER LOADER, ENGINE, SKID STEER LOADER - TIER 4F - NA, SKID STEER LOADER, SKID STEER LOADER - NRC, SKID STEER LOADER TIER 4, COMPACT TRACK LOADER, COMPACT TRACK LOADER - NRC, CASE UNIT LOADER including models 1150B, 1150D, 1150E, 1150G, 1150H, 1150M LT, 1150M WT, 1150M WT/LGP, 1155D, 1155E, 1450, 1450B, 1455B, 1650M LGP PAT, 1650M XLT BD, 1650M XLT PAT, 1700, 1835C, 1838, 1840, 2050M LGP BD, 2050M LGP PAT, 2050M LT BD, 2050M LT PAT, 2050M XLT BD.

Frequently asked questions

What is the part number?

The manufacturer part number is 88559.

Is this a genuine OEM part?

Yes. Southeastern Equipment stocks OEM and quality aftermarket parts for heavy equipment. Contact us if you need a specific OEM source or aftermarket option.

Will this fit my machine?

See the compatible equipment list above. If your model is not listed, call us with your machine's serial number and we can confirm.

Where does this ship from?

Southeastern Equipment Company ships parts nationwide from our US warehouse. Orders placed before 2 PM ET typically ship same day.

Free pickup at any of our 17 branches across Ohio, Indiana, Michigan, and Kentucky. Select your preferred branch at checkout.

30-day no-fault returns. Bought the wrong part? Send it back for a full refund — no restocking fees, no minimums.