What Bearings, Races, and Grease Seal do I Need to Replace My Timken 2785 and 1779 Bearings?
Updated 09/26/2025 | Published 05/02/2025 >
Products Featured in This Question
Question:
I know nothing about trailers. I need the bearings and what ever else to rebuild a hub. I do have part numbers if that helps. inner bearing says Timken 2785 Outer bearing only has a number 1779. Any help would be greatly appreciated.
asked by: Nathan T
Expert Reply:
Hello Nathan,
I had to get some of the parts added to the site, so my apologies for the delay in getting an answer.
You will need one of each per hub:
-Timken 2785 Tapered Roller Bearing Single Cone - Imperial - 1.75" ID for Axles & Hubs # TMK78ZR, with race # TMK88ZR (this might not pop up on our site til tomorrow 5/9 as it was just added)
- Timken Replacement Trailer Wheel Bearing - 1779 # TMK94FR with cup/race # TMK66FR
- Cotter Pin - 1/8" Thick x 1-3/4" Long # 165649
- For the seal you will want to double check the measurements, I am showing that you need Timken Grease and Oil Seal # TMK98ZR which has the measurements I.D. 2.250" / O.D. 3.376". If your measurements are way different, just comment them below.
Don't forget the grease, LubriMatic Prime Guard High Temperature Wheel Bearing Grease - Red - 16-oz Can # L11380
I attached a help article as well for replacing bearings, just in case you need it for reference.
What kind of trailer is the hub on? Not too common of bearing sizes that I deal with on the daily.
Product Page this Question was Asked From
Cotter Pin - 1/8" Thick x 1-3/4" Long
- Accessories and Parts
- Trailer Suspension Parts
- Cotter Pin
- ABS Fasteners
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Article: Replacing the Bearing, Races and Seals on a Trailer Hub
- Search Results: cotter pin
- Search Results: spindle cotter pin
- Search Results: grease lubricants sealants adhesives
- Search Results: gs 2125dl seal
- Shop: Dexter Multipurpose High Temperature Lithium Grease - 1 lb
- Shop: Timken Grease and Oil Seal - Double Lip - I.D. 1.719" / O.D. 2.565" - 473336
- Q&A: Replacement Parts For Dexter D40 EZ Lube 4,000LB Trailer Axle # 7369991
- Q&A: Replacement Grease Seal for 3,500 lb Dexter Axle on Forest River Trailer
- Q&A: Bearings and Dust Caps Compatible with Dexter Axles on Travel Trailer
- Shop: Grease Seal - Double Lip - ID 1.719" / OD 2.565" - for 3,500-lb Axles
- Shop: Cotter Pin - 1/8" Thick x 1-3/4" Long
- Shop: Hub Bearing Kit for Lippert, Dexter, and AL-KO Axles - 3,500 lb with #84 Spindle
- Shop: Grease Seal - Double Lip - ID 1.719" / OD 2.565" - for 3,500-lb Axles - Qty 2
- Shop: Seal Puller
- Shop: Suspension Enhancement
- Video: Firestone Ride-Rite Air Bags with Easy Mount Compressor Feature Breakdown
- Search Results: trailer hitch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Shop: Trailer Hitch
- Article: Trailer Wiring Diagrams
- Search Results: trailer tires and wheels
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Shop: Trailer Wiring
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Article: How to Measure for Trailer Hitch Drop
- Search Results: trailer wiring
- Q&A: Best Suspension Upgrade for 33" Tandem Axles: Road Armor vs Dexter EZ Flex for Ember 22ETS
- Video: One Year Later | Firestone Airide Helper Springs and Heavy Duty Air Compressor
- Shop: Brake Controller




Kate F.
9/26/2025
Hey Nathan, Did you get a chance to check the measurements for the seal to ensure it's the right fit for your trailer hub? I'm curious to know how it all worked out for you, as it could help others who are looking to rebuild their hubs too.