Coats 8181183 Nylon Insert Lock Nut, 5/16-18 GR4

A fastener that backs out mid-job isn't just annoying -- it takes the machine offline. The Coats 8181183 is a 5/16-18 nylon insert lock nut rated GR4, and it's the OEM-spec replacement for Coats tire changers and balancers. The nylon insert grips the threads and stays put under the vibration and torque that shop equipment generates every single day. Standard hex nuts can walk loose over time; the insert prevents that without any secondary locking method. That's the whole point of a lock nut, and this one does the job.

Steel construction with a corrosion-resistant coating means it holds up in a working shop environment without rust becoming a problem down the road. If you're doing a repair and need to replace a fastener, getting the correct part number matters -- off-spec hardware with the wrong thread engagement or insert fit will let you down faster than the original ever did. Coats equipment runs across a wide range of tire changers and balancers, and the 8181183 is the designated replacement fastener for that service work. It's stocked and ready to ship, so you're not waiting on a specialty order to get your machine back together. One nut. Right fit. Back in service.

Specifications

Part Number 8181183
Part Type Nylon Insert Lock Nut
Thread Size 5/16-18
Grade GR4
Material Steel with nylon insert
Finish Corrosion-resistant coating
Compatible Equipment Coats Tire Changers and Balancers
Application Tire changer and balancer repair and maintenance

Ready to Ship

The correct OEM-spec lock nut for your Coats equipment. Add it to your cart and we'll get it moving.

About the Brand

Coats Company

View All Coats Company Products

Garage Supply Guys Frequently Asked Questions

If something's not working out, just let us know. Keep in mind that some items might have a restocking fee. Check the product page for the specifics.
No worries, we've got you covered. We can send replacement parts or arrange for a new delivery. Just make sure to inspect everything when it arrives and give us a heads up right away if something's off.
All the details are at the bottom of our site under Shipping & Return Policy. You'll find everything about returns, freight damage, and any brand-specific rules.
Most larger items like car lifts and heavy equipment ship free, but depending on the brand there might be freight costs. Smaller items almost always have shipping fees via UPS, USPS, FedEx, etc. We'll show you any extra costs before you check out.
Shipping estimates are just that — estimates, and they're not guaranteed. Weather, freight delays, and carrier issues can throw things off, especially with bigger items. If you're on a tight timeline for installation, it's smart to give yourself some wiggle room.
Yep! Once it ships, we'll email you the tracking info so you can keep tabs on your delivery and plan accordingly.
We always send tracking info once your order ships. If it's been more than five business days and you haven't heard anything, just shoot us a message at support@garagesupplyguys.com or hit us up through the Contact Us page. We'll figure out what's going on.
Make sure whatever you're buying will actually fit your space. That means checking ceiling height, floor space, power requirements, and whether freight delivery can even get to your location. Trust us, it's way easier to confirm these details upfront.
Read through the product details carefully, especially for heavy or specialized items. If you're not sure about fit, shipping, installation, or anything else, just ask. We'd rather help you get it right the first time.
You'll get a confirmation email right away once you place your order. For most items like car lifts, parts, and shop tools, we'll have them shipped out within five business days if they're in stock. This goes for all major brands and replacement parts.
We don't offer installation services ourselves, but we can put you in touch with qualified installers in your area who you can work out pricing with directly. We can also handle this for you after your purchase.
Just reach out to us after your purchase and we'll connect you with trusted installers in your area. You can negotiate pricing and scheduling directly with them, or we can help coordinate the whole process for you.
Some items can be installed by experienced DIYers, but larger equipment like car lifts typically require professional installation for safety and warranty reasons. Check the product specifications and manufacturer requirements before deciding.
Yes! We're authorized dealers for all the major brands we carry. This means you get full manufacturer warranties, genuine parts, and proper support. You can always verify our dealer status directly with the manufacturer if you'd like.
It means you're getting the real deal - genuine products with full manufacturer warranties, access to official support, and the peace of mind that comes with buying from a legitimate dealer. No gray market products or void warranties here.