How to oil compound bow axles

The cam axle is the highest-friction point on a compound bow. Every draw cycle rotates the cam on the axle pin under significant mechanical load — thousands of times a season. When the axle is properly lubricated that friction is controlled and consistent. When it runs dry, draw cycle variation, audible cam drag, and accelerated wear follow — usually before the archer notices anything is wrong.

Oiling compound bow axles correctly takes less than five minutes. The process is simple. The two things that matter are using the right product and applying the right amount. This guide covers both.

Step Zero — Know Your Cam Type Before You Oil Anything

Before applying any lubrication to your cam axles, you need to know which type of cam system your bow uses. This is the most important thing to get right — applying oil to the wrong cam type wastes product at best and attracts grit at worst.

Open bushing cams — need lubrication

Older compound bows and some current models use cams that rotate on open bushings — a metal sleeve inside the cam that the axle pin passes through. The gap between the axle pin and the bushing is the contact surface that needs lubrication. You can usually see the axle pin exposed at each end of the cam where it passes through the cam body. These cams need periodic silicone oil applied directly to the axle pin.

Sealed bearing cams — do not lubricate externally

Most compound bows built in the last decade — from major brands including Hoyt, Mathews, Bowtech, and PSE — use sealed cam bearings. These are factory-packed with grease at manufacture and completely enclosed. You cannot reach the bearing internals from the outside. Applying oil to the exterior of a sealed bearing does nothing to help the bearing and creates a surface that attracts grit near your string and cable system.

How to tell which type you have: Check your bow's owner manual or the manufacturer's website. If you can see the axle pin exposed at the cam ends and feel slight play when wiggling the cam laterally, you likely have open bushings. If the cam feels completely solid with no visible axle gap, you likely have sealed bearings. If unsure, ask at your local archery pro shop before lubricating.

If your bow has sealed cam bearings — stop here. The rest of this guide applies to open bushing systems only. If your sealed bearings feel rough or gritty, that is a press service or bearing replacement job, not a lubrication job.

What You Need

• Silicone oil — GNP Defend Silicone Oil or any silicone-based lubricant. Never use WD-40, 3-in-One oil, gun oil, or any petroleum-based product.
• Lint-free cloths — two or three. One for cleaning, one for wiping excess after application.
• Cotton swabs — optional but useful for cleaning tight spaces around the axle pin before lubricating.

That's it. No special tools required. No bow press. This is a task you can do at home in a few minutes between sessions.

Why Silicone Oil — And Why Not WD-40

The cam axle area is surrounded by composite cam body material, rubber components, and synthetic string fibers. Petroleum-based lubricants — including WD-40 — contain solvents and petroleum distillates that degrade these materials over time. They also evaporate quickly and leave behind sticky residues that trap grit at the exact contact point you're trying to protect.

Silicone oil is chemically inert — it does not react with any of the materials surrounding the axle. It creates a stable lubricating film that stays in place between applications, repels moisture, and leaves no sticky residue. It is the product that bow manufacturers recommend for this application, and it is the only product that is safe for every material in a compound bow's cam assembly.

WD-40 specifically: its name stands for Water Displacement, 40th formula. It is a penetrating solvent designed to displace moisture, not a lubricant. It provides almost no lasting friction protection and its solvent content actively damages the composite and rubber materials in modern bow cams. Do not use it on your bow axles.

How to Oil Compound Bow Axles — Step by Step

Step 1 — Lay the bow on a flat, stable surface

Work on a clean, stable surface with good lighting. You need to see the axle pin clearly at each cam end. A folded towel on a workbench works well — it keeps the bow from sliding and protects the finish.

Step 2 — Clean the axle area first

Before applying any lubricant, wipe the axle pin and the cam surface immediately around it with a clean, dry lint-free cloth. Remove any existing grit, dust, or old lubricant residue. If there is debris packed into the gap between the axle pin and the cam body, use a dry cotton swab to clean it out.

This step matters. Applying fresh lubricant over existing grit suspends the abrasive particles in the oil film and grinds them into the contact surface rather than protecting it. Always clean before lubricating.

Step 3 — Apply silicone oil to the axle pin

Apply a small amount of GNP Defend Silicone Oil directly to the axle pin at each end of the cam — where the pin enters the cam body. One short burst of aerosol or one small drop per side is the correct amount. The goal is a thin, even film at the contact point — not a soaking.

Apply to both cams. Each cam has two axle ends — top and bottom where the pin exits the cam body through the limb. Apply to each contact point: four application points total on a standard two-cam compound bow.

Keep oil away from strings and cables. Apply precisely to the axle pin only. Excess oil that migrates onto string fibers breaks down the fiber structure and dramatically shortens string life. If oil gets on the string, wipe it off immediately with a clean dry cloth.

Step 4 — Work the oil in

Once the oil is applied, gently cycle the bow by drawing it slowly by hand several times. This distributes the lubricant through the contact surface between the axle pin and the bushing. You should feel the cam rotation become slightly smoother as the oil works into the contact zone.

Do not draw to full draw for this step — a slow, partial draw is enough to distribute the lubrication. The goal is to work the oil into the bushing gap, not to shoot.

Step 5 — Wipe away excess

After cycling the bow, wipe down the cam body and axle area with a clean cloth to remove any excess oil that has migrated away from the contact zone. Pay particular attention to areas near the string grooves and any surface where the bowstring or cables make contact.

A thin film at the axle contact point is what you want. Any oil you can see pooling or running on the cam surface is excess — remove it.

Step 6 — Check the draw cycle

After lubricating, draw the bow slowly and feel for the draw cycle. Properly lubricated cam axles should feel smooth with no grinding, roughness, or inconsistency. If you still feel roughness after lubricating, the axle or bushing may be worn and require a professional press inspection rather than more oil.

How Often Should You Oil Compound Bow Axles?

Every 1,500–2,000 shots under normal shooting conditions. At 100 shots per session that's roughly 15–20 sessions — about one hunting season or a few months of regular practice. This interval is based on manufacturer guidance from major bow brands and represents the point at which friction buildup begins to affect draw cycle consistency before any obvious warning signs appear.

Lubricate sooner if:

• You have been hunting or shooting in rain, mud, or heavy dust
• You notice any gritty feeling when spinning the cams by hand
• You hear squeaking or creaking during the draw cycle
• You see visible surface rust on the axle pins after moisture exposure
• Your draw cycle feels heavier or less consistent than usual

For the full compound bow maintenance schedule including all intervals and tasks, read: Compound Bow Maintenance Schedule — What to Do and When.

Common Axle Lubrication Mistakes to Avoid

• Using WD-40 — it is a solvent, not a lubricant. It will evaporate within hours, leave a grit-attracting residue, and degrade the composite and rubber materials around your cam axle. Use silicone oil.
• Over-lubricating — excess oil migrates onto strings and cables. One small application per axle end is all that is needed. More is not better and can cause significant string damage.
• Lubricating sealed bearings externally — if your bow has sealed cam bearings, do not apply oil to them. The oil cannot reach the bearing internals and only creates a grit-attracting surface near your string system.
• Lubricating over dirt — always clean the axle area before applying fresh oil. Lubricating over grit suspends the abrasive particles in the oil film and accelerates wear.
• Skipping one cam — always lubricate both cams. Uneven friction between the left and right cam axles causes cam timing drift that is difficult to tune out and often misdiagnosed as a form problem.
• Using grease instead of oil — white lithium grease and similar thick lubricants are too viscous for cam axle points. They attract grit, build up in the cam groove area, and can affect string tracking. Use silicone oil only at axle points.

Frequently Asked Questions

What oil should I use on compound bow axles?

Silicone oil is the correct choice for compound bow axles. It is chemically inert, safe for all bow materials, provides lasting lubrication, and repels moisture. Never use WD-40, petroleum-based oils, or general-purpose sprays — these degrade composite and rubber materials and leave grit-attracting residues.

How often should I oil my compound bow axles?

Every 1,500–2,000 shots under normal conditions. After shooting in rain, mud, or heavy dust, inspect and re-lubricate sooner regardless of shot count. If you notice gritty cam rotation, squeaking, or draw cycle inconsistency, lubricate immediately.

Do I need to oil sealed cam bearings?

No. Sealed cam bearings are factory-packed with grease and do not need or benefit from external lubrication. Oil applied to the outside of a sealed bearing cannot reach the bearing internals. If sealed bearings feel rough or gritty, that is a bow shop service or replacement job.

Can I use WD-40 on my compound bow axles?

No. WD-40 is a penetrating solvent, not a lubricant. It evaporates quickly, leaves a residue that traps grit, and contains petroleum distillates that degrade the composite and rubber materials surrounding the cam axle. Use silicone oil instead.

How much oil should I put on compound bow axles?

Very little — one small drop or a short burst of aerosol per axle end is sufficient. Excess oil migrates onto bowstrings and cables, breaking down the fiber structure and shortening string life. A thin, even film at the contact point is all that is needed.

What happens if I don't oil my compound bow axles?

Dry cam axles develop friction buildup that affects draw cycle consistency before producing any audible warning signs. Over time you may notice inconsistent groups, gritty cam rotation, squeaking during the draw, and eventually visible wear on the axle surfaces. The damage is cumulative — the longer axles run dry, the more wear accumulates.

Summary

Check your cam type first — open bushing cams need oil, sealed bearing cams do not. Clean the axle area before lubricating. Apply a small amount of silicone oil to each axle pin end. Cycle the bow to distribute. Wipe away excess. Do this every 1,500–2,000 shots or whenever you notice the warning signs of a dry axle.

View GNP Defend Silicone Oil →    Full Lubrication Guide →    Complete Bow Care Guide →