Anti-Seize on Plow Bolts: It Helps Removal and Changes the Torque Question

Scenario: rusted-in bolts are a nuisance, so the shop wants to put anti-seize on the threads. Direct answer: it can help with removal, but a lubricated bolt reaches higher clamp load at the same torque, so the torque value you use must account for it. Two vendor documents I read on 24 October 2026 say so; they are vendor sources, not a standard, and they do not address plow edges. Ask your plow maker which torque applies to lubricated threads.

What the sources say

The sources disagree about the number and agree about the mechanism.

• An anti-seize vendor’s torque note says the amount of torque applied determines clamp load, and that applying torque to a fastener with anti-seize on the threads will increase the clamp load compared with an unlubricated bolt.
• The same note says torque values should be reduced by 25% for lubricated fasteners to achieve similar stress to a dry fastener, that most listed torque values are based on non-lubricated fasteners, and that for critical applications the torque coefficient (nut factor) must be determined independently.
• A lubricant maker’s article explains K-factor as the relationship between torque and clamp force, typically between 0.1 and 0.25, says most lubricants reduce it, and says that if K-factor is too low the bolt may be overtightened, so a lubricant and fastener should be tested together.

What this means for a shop

The shop-level answer is a written rule, not a better lubricant.

1. Do not mix: if a torque value is given for dry threads and you lubricate, you may overtighten at that value.
2. Ask: request the plow maker’s torque for the bolt size and grade, and ask whether it assumes dry, oiled or anti-seize threads.
3. Be consistent: use the same method on every bolt of a set, and write it in the procedure.
4. Test if critical: if failures or loosening occur, consider having the combination tested.

Steps for a procedure

Anti-seize changes the torque, so the decision has to be made before the wrench, not after.

1. Clean the threads and remove loose rust. A dirty thread gives an unpredictable friction value.
2. Decide dry or lubricated, which product, and write it down. A procedure that varies by mechanic is not a procedure.
3. Apply a thin, even coat if lubricating. Excess compound hydraulically locks the joint and reads as full torque.
4. Tighten to the value the maker gives for that condition. Do not reuse the dry figure on a lubricated thread.
5. Recheck after the first shift. Settling is normal; a loose bolt after one shift is not.

What this does not say

• It gives no torque for any plow bolt; the 25% figure is the vendor’s general note, not a rule for your fastener.
• It does not recommend any product.

Boundary: The 25% reduction is a general vendor statement and not a torque for any plow bolt; ask the plow maker for the torque that applies to your threads and fastener grade.