---
title: "Which lubricant is safe on rubber seals?"
description: "Silicone grease on most rubbers, and a PTFE or fluorosilicone product on silicone rubber itself — petroleum products swell and destroy natural rubber and EPDM. The r"
url: https://atoneplace.net/which/lubricant-rubber-seal/
site: "At One Place"
---

# Which lubricant is safe on rubber seals?

**Which lubricant is safe on rubber seals?: Silicone grease on most rubbers, and a PTFE or fluorosilicone product on silicone rubber itself — petroleum products swell and destroy natural rubber and EPDM.**

Elastomer compatibility is the whole question, and it is counterintuitive because the answers are almost inverted. Natural rubber and EPDM are hydrocarbon-based and are swelled and destroyed by hydrocarbon oils, so petroleum jelly on a car door seal or a plumbing O-ring is a slow way of wrecking it. Silicone grease is chemically unrelated to those rubbers and leaves them alone — but for the same reason it swells silicone rubber, so a silicone O-ring wants a PTFE or fluorosilicone product instead. Nitrile, by contrast, is fine with mineral oil and attacked by some other solvents. Where the seal is critical — a plumbing fitting, a diving regulator, a pressure vessel — the manufacturer names a compatible lubricant, and that name is the answer.

## The options, ranked

*Ranked best-first for the stated job. The third column is why the others exist.*

| Option | Good at | Bad at |
| --- | --- | --- |
| Silicone grease | Compatible with most elastomers, waterproof, stable across a wide temperature range, and the standard for O-rings and door seals. | Swells silicone rubber itself, and contaminates any surface that is to be painted or glued. |
| PTFE-based lubricant | The right choice where the seal is silicone rubber, and it leaves a dry film. | Less durable than grease on a heavily worked seal. |
| Rubber seal conditioner | Formulated for car door and boot seals to keep them supple and stop them freezing shut. | Needs reapplying seasonally. |
| Mineral oil, petroleum jelly or general spray | Nothing on natural rubber or EPDM. | Hydrocarbons are absorbed by these rubbers, which swell, soften and lose their sealing shape permanently. |

## Technique that changes the outcome

1. Identify the rubber before choosing: EPDM and natural rubber for door and window seals, nitrile for most oil-side O-rings, silicone for high-temperature seals
2. Apply a thin film; excess collects grit and does no more good
3. Clean the seal first, since grit under a lubricated seal grinds it
4. Treat car door seals before winter so they do not freeze to the paint

## What goes wrong

- Petroleum jelly or mineral oil on natural rubber or EPDM
- Silicone grease on silicone rubber
- Silicone anywhere near a surface that will be painted afterwards

> Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.

## Other lubricant questions

| For | Use |
| --- | --- |
| A bike chain | Wet lube for wet conditions, dry lube for dry and dusty ones, wax if you want the cleanest and lowest-friction option — and not a general penetrant. |
| A lock | A dry lubricant — powdered graphite or a PTFE spray. Oil and general penetrating sprays gum locks up and are the classic way to ruin one. |
| A squeaky door hinge | A drop of light machine oil or a smear of white lithium grease on the pin — and lift the pin out to clean it, which is usually the actual fix. |
| A seized bolt | A dedicated penetrant or a 50/50 acetone and automatic transmission fluid mix, plus time, heat cycles and shock — and anti-seize on reassembly. |
| A squeaky floor | Talc, graphite or powdered soapstone worked into the joint as a stopgap — the real fix is screwing the board down to the joist. |
| A sticky drawer | Paraffin wax or beeswax on wooden runners, dry PTFE on metal ones — and never oil on wood. |
| A garage door | White lithium grease or a garage-door lubricant on rollers, hinges, springs and bearings — and not on the track, which should be clean and dry. |

## Common questions

### Which lubricant is safe on rubber seals?

Silicone grease on most rubbers, and a PTFE or fluorosilicone product on silicone rubber itself — petroleum products swell and destroy natural rubber and EPDM.

### What should I avoid?

Petroleum jelly or mineral oil on natural rubber or EPDM Silicone grease on silicone rubber Silicone anywhere near a surface that will be painted afterwards

## Related pages

- [Which lubricant should I use on a bike chain?](https://atoneplace.net/which/lubricant-bike-chain/)
- [Which lubricant should I use on a lock?](https://atoneplace.net/which/lubricant-lock/)
- [Which lubricant stops a squeaky door hinge?](https://atoneplace.net/which/lubricant-door-hinge/)
- [Which penetrating fluid frees a seized bolt?](https://atoneplace.net/which/lubricant-seized-bolt/)
- [What should I put on a squeaky floorboard?](https://atoneplace.net/which/lubricant-squeaky-floor/)
- [What should I put on a sticky drawer?](https://atoneplace.net/which/lubricant-sticky-drawer/)
- [Which lubricant should I use on a garage door?](https://atoneplace.net/which/lubricant-garage-door/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)