New 0S1591 Cap Screw Replacement suitable for Caterpillar Equipment
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Description for 0S1591 Hex Bolt
â–¶Specification for 0S1591 Hex Bolt
â–¶Exact Fit Guarantee for 0S1591 Hex Bolt
â–¶| Dimensions | 1.77x0.63x0.63 |
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Frequently Asked Questions
What is the Caterpillar 0S1591 cap screw used for?
A: The 0S1591 cap screw is used to fasten components in Caterpillar heavy equipment assemblies, including engine covers, housings, and brackets. Cap screws offer high clamping force and are typically used where a hex head bolt would not fit due to clearance constraints.
What are the specifications of the 0S1591 cap screw?
A: This cap screw is manufactured to meet or exceed OEM specifications for thread size, thread pitch, length, and tensile strength as defined by Caterpillar. Refer to your parts manual for full dimensional details.
Is the 0S1591 a direct replacement for the original?
A: Yes. This is a high-quality aftermarket cap screw designed as a direct replacement, matching all critical dimensions and mechanical properties of the original Caterpillar fastener.
Which Caterpillar machines use the 0S1591 cap screw?
A: This cap screw is compatible with a range of CAT machinery. Check your equipment manual or reach out to Propel Parts for help verifying fitment.
Explore our complete inventory of heavy equipment hardware parts including cap screws, bolts, and nuts for Caterpillar machines.
What tool is needed to install this cap screw?
A: Cap screws typically require a hex key (Allen wrench) or socket for installation. The specific tool size depends on the cap screw head dimensions. Refer to your service manual for the correct tool size and torque specification.
Should cap screws be replaced during overhauls?
A: Yes. It is best practice to replace cap screws during major overhauls or whenever they show signs of thread wear, corrosion, or deformation. Fresh high-quality aftermarket fasteners ensure proper clamping during reassembly.
What warranty is included with this cap screw?
A: All Propel Parts products carry a 12-month warranty from the invoice date against manufacturing and material defects. Same-day shipping is available for weekday orders placed by 3pm ET.

We know equipment downtime costs money, so fast and reliable shipping is a priority at Propel Parts. Orders placed on weekdays before 3:00 PM ET typically ship the same day, with expedited delivery options available for many locations when time is critical.
We ship across the U.S., Canada, and over 130 countries worldwide, helping customers keep machines running wherever they operate. Available shipping methods and delivery estimates are shown at checkout so you can select the option that best fits your timeline.
Tracking information is emailed within 24–48 hours after your order is processed, giving you full visibility from dispatch to delivery and peace of mind that your parts are on the way.

Our refund policy is simple. We offer a 30-day, no-hassle return policy, and we make every effort to provide the best service and highest-quality parts possible. If you’re not fully satisfied with your purchase, you may return it within 30 days for a refund. Full details are available on our Returns Policy page.

Buy with confidence. All parts from Propel Parts are covered against material or manufacturer defects for 12 months from the original invoice date. We stand behind every part we sell, so you can count on reliable performance and dependable support. Full details are available on our Warranty Policy page.
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