Should the Same Two 4.80-12 Tires Have the Same Outer Diameter.
Question:
I just bought new wheels and tires for my boat trailer. They are 4.80-12. They were delivered mounted and inflated. The difference in overall outside diameter was visually apparent to me. I measured them to be 3/8” to 1/2” different on nominal 20” diameter. What is an acceptable tolerance for OD or side to side tires? The boat, motor and trailer combined is about 1,400lbs. They were delivered with different pressure in each and sat outside in the cold for a few hours. I have set them to same pressure and brought them inside to equalize these possible reasons for the difference. Please advise. Thanks
asked by: Gary
Expert Reply:
Assuming you have the same two 4.80-12 tires, they should have the same outer diameter. It sounds like the reason for the difference was the different psi in each tire. Once you have filled both to the max psi, the diameter should be identical.
The only other reason they might vary is if it is two different tires. For example, the Kenda # AM10062 has an outer diameter of 20.5" when inflated and the Taskmaster # TT48012C has an outer diameter of 20.63" even though both are 4.80-12 tires.
Products Referenced in This Question
Kenda K353 Bias Trailer Tire - 4.80-12 - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range C
- 4.80-12
- 12 Inch
- Kenda
more information >
Taskmaster 4.80R12 Radial Trailer Tire - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Radial Tire
- Load Range C
- 4.80-12
- 12 Inch
- M - 81 mph
- Taskmaster
more information >
Product Page this Question was Asked From
Westlake ST225/75R15 Radial Trailer Tire - Load Range E
- Trailer Tires and Wheels
- Tire Only
- Radial Tire
- Load Range E
- 225/75-15
- 15 Inch
- L - 75 mph
- Westlake
more information >
Continue Researching
- Q&A: Trailer Suspension Hanger Kit for Slipper Springs and 38 inch Wheelbase
- Q&A: 10k Dexter Replacement Hub for a 8-415
- Article: What is Overlanding? How to Start your Overlanding Journey
- Article: Wiring Trailer Lights with a 4-Way Plug (It's Easier Than You Think)
- Q&A: Difference Between Trailer Tire Sizes ST205/75R15 and ST225/75R15
- Article: How to Choose the Right Trailer Hitch Class
- Q&A: Can Electric Trailer Brake Kit # AKEBRK-2 be Submerged in Water
- Q&A: Will Swagman Bike Rack Fit Spare Tire with Hard Plastic Cover
- Article: Trailer Wiring Diagrams
- Q&A: Wiring a Camper Shell Third Brake Light on a 2017 Chevrolet Silverado
- Q&A: Replacement Fan Recommendation for the MaxxAir 4700K
- Article: RV Cell Boosters, How Do They Work?
- Article: 7 Common Questions Everyone Has About Trailer Tires
- Article: Trailer Tire Sizing