How to Identify the Right Oil Seal by Part Number or Size?

Ever stared at an oil seal with a smudged label or partial number and thought, “How on earth do I find the right one?” I’ve been there. It’s frustrating—and costly when you order the wrong seal.

To identify the correct oil seal, you can match it by part number (OEM or manufacturer reference) or by measuring key dimensions: inner diameter (ID), outer diameter (OD), and thickness. Cross-referencing these details ensures a precise replacement.

If you’ve got a sample, a size, or just a number—we can help you match it. In this guide, I’ll break down the two methods I use daily to identify oil seals and avoid costly mismatches.

What information do I need to identify an oil seal?

There are two ways to start:

1. By Part Number
Most OEM seals have a reference number printed or engraved, like “TOYOTA 90311-47027.” This number allows us to cross-reference with our catalog and find the exact match.

2. By Size
If there’s no number, just measure:

• ID: fits onto the shaft
• OD: fits into the housing
• Width/Thickness: overall seal height

For example, a seal with ID 25 mm, OD 40 mm, and thickness 7 mm might be listed as 25x40x7 in catalog format.

We’ve matched thousands of seals this way—whether it’s a forklift in Brazil or a water pump in Dubai.

How do I use a part number to match a seal?

If your seal has a visible number, that’s your golden ticket.

Here’s what you do:

• Clean the seal and check sidewalls for engraved/printed numbers
• Search that number in our cross-reference list
• Or, send it to us via WhatsApp—we’ll find the match within hours

For example:

• “TOYOTA 90311-47027” ➜ Matched to TOYOTA Oil Seal guide
• “TC 25x40x7” ➜ Standard type TC double-lip seal, available here: Oil Seal Product Page

We also accept PDF catalogs, images, and OEM reference sheets from your local market.

How do I measure a seal if there’s no number?

No part number? No problem. Here’s my go-to measuring method:

Step 1: Clean the seal
Step 2: Use a digital caliper
Step 3: Measure:

• ID (hole size)
• OD (outer edge)
• Thickness (seal height)

Example:
You measure ID = 30.1 mm, OD = 47.8 mm, Width = 7.2 mm ➜ likely a 30x48x7 seal.

Even if your reading is slightly off (e.g., 30.1 mm), we’ll help you round it to the standard size.

Pro Tip: Take a photo of the seal next to a ruler and send it to us—we’ll match it manually.

Can I cross-reference seals between brands?

Absolutely. Many seals share standard dimensions and profiles across brands.

We offer cross-reference services for:

• NOK, TTO, SKF, Corteco, NAK, Parker
• OEMs like Toyota, Mitsubishi, HINO, VW, BENZ

Let’s say you have a NOK TC 25x40x7—we can provide you the same spec from our factory.

We’ve also helped distributors build country-specific cross charts based on regional part numbers.

Need a customized chart? Just email us.

Conclusion

Whether you have a number, a sample, or just a caliper—there’s always a way to identify the right oil seal. The key is knowing what to measure and where to look.

Call to action

Still unsure which oil seal you need?
📧 Email: [email protected]
📱 WhatsApp: +86 17622979498
Send us a part number, sample photo, or your own catalog—we’ll match and quote within hours.

People Also Ask