need tire advice
Last week I had my first blowout. Nobody's fault but mine, I was going too fast for the tires (rated at 65), I was doing just shy of 75. Normally I drive up and down the West coast but this trip I...
Forum Discussion
Regulations / standards are based on an assumptions and historical data.
Historically (when the regs were written in the 70's) trailers were 3,000# single axle units and with speed limits in place at that time were towed at less than 55. There were no slides.
The regulation that the total load capacity of the tires on any axle must exceed the load capacity of the axle (GAWR) assumed competent design by the vehicle manufacturer with side to side balance on an axle to be very close to 50/50. My guess would be +/- 2% variation or less.
The reality of today's RV market is dual and triple axle units with some tires being loaded by 1,000# more than another. While 1,000 may be the exception it is normal to see 5th wheel trailers with individual tire load variation in the 15 to 20% range.
To those that say the Regs need to be updated I answer that I agree but the reason they are not will get this post deleted as it gets into political commentary.
BOTTOM LINE
Many buy the RV based on bling and have little or no understanding that a large RV is not designed or manufactured with the same level of engineering attention to detail as today's car are.
RV Mfg are price driven because that is what the majority of the buyers demand. It is a fact that over half of all RVs have one or more tire in overload condition. It is an observable fact that many RVs are traveling faster than 65. If 90% of the large RVs made today have tires made in China why would you not expect 90% of the tire failures to be on tires made in China?
People have asked for advice but when the answer to their question isn't the low cost answer they want they shoot the messenger. I am aware of a couple people with a working knowledge of tire regulations and a couple with working knowledge of tire engineering. If you don't like the answers that are quoting regulations or telling you of what they know as tire engineers then please stop asking the same question over and over again.
Tires have limits of speed, Load and inflation. When you run outside those limits why are you surprised that your chances of failure increase?
I believe the OP has been given a few options and way more information, and noise than he wanted. I believe it is time we move on.
--Stepping off soap box--
Historically (when the regs were written in the 70's) trailers were 3,000# single axle units and with speed limits in place at that time were towed at less than 55. There were no slides.
The regulation that the total load capacity of the tires on any axle must exceed the load capacity of the axle (GAWR) assumed competent design by the vehicle manufacturer with side to side balance on an axle to be very close to 50/50. My guess would be +/- 2% variation or less.
The reality of today's RV market is dual and triple axle units with some tires being loaded by 1,000# more than another. While 1,000 may be the exception it is normal to see 5th wheel trailers with individual tire load variation in the 15 to 20% range.
To those that say the Regs need to be updated I answer that I agree but the reason they are not will get this post deleted as it gets into political commentary.
BOTTOM LINE
Many buy the RV based on bling and have little or no understanding that a large RV is not designed or manufactured with the same level of engineering attention to detail as today's car are.
RV Mfg are price driven because that is what the majority of the buyers demand. It is a fact that over half of all RVs have one or more tire in overload condition. It is an observable fact that many RVs are traveling faster than 65. If 90% of the large RVs made today have tires made in China why would you not expect 90% of the tire failures to be on tires made in China?
People have asked for advice but when the answer to their question isn't the low cost answer they want they shoot the messenger. I am aware of a couple people with a working knowledge of tire regulations and a couple with working knowledge of tire engineering. If you don't like the answers that are quoting regulations or telling you of what they know as tire engineers then please stop asking the same question over and over again.
Tires have limits of speed, Load and inflation. When you run outside those limits why are you surprised that your chances of failure increase?
I believe the OP has been given a few options and way more information, and noise than he wanted. I believe it is time we move on.
--Stepping off soap box--
