Towing Speeds

3 years ago when I was in California, I drove the speed limit of 55 mph, or actually a few miles over. Everyone, including 18 wheelers were passing me. I drove slow because I didn't know how sensitive the local LEO's were, especially since I was from across the US.

ROBERTSUNRUS wrote:

Larryzv7 wrote:
Why do you think States, like California, have a maximum speed of 55-mph when towing? Someone told me that the tires on most trailers, including semi-trucks, are not made for speeds over 55-mph; is this correct?

:) Hi, it is normal for people in California to do at least ten MPH over the speed limit. Can you imagine if the California limits were higher?

How fast you can go is not nearly as important as how fast you can stop.

Tire failure is probably the smallest percentage of the reasons for accidents. Impaired or just plain over driving your stopping skills has to rank higher.

It is also in the math, twice the speed means four times the amount of energy that needs to be transferred to the pavement to stop. Hopefully it is transferred through the tires and not the mangled wreckage of the tow vehicle and trailer sliding down the road.

In my experience, when you have to stop fast, a lot of pavement goes by before you and your TT have come to a stop.

Larryzv7 wrote:
Why do you think States, like California, have a maximum speed of 55-mph when towing? Someone told me that the tires on most trailers, including semi-trucks, are not made for speeds over 55-mph; is this correct?

:) Hi, it is normal for people in California to do at least ten MPH over the speed limit. Can you imagine if the California limits were higher?

87 MPH is correct for 1100/22 hi profile Michelin tires and my Pete tops 91 MPH at 2100 RPM and in 15th. They actually fudge on specs and you can go anywhere from 10 to 305 higher than rated. Michelin 1100/22r hi profile Up to 87 mph Speed Rating from Michelin's site.

DutchmenSport wrote:

DanNJanice wrote:
... The faster you drive the more time to stop, the heavier you are the more time to stop.

True... and remember, time equals distance you know. It takes more distance to stop a 15,000 pound 5er, than it does to stop a 3,000 pound car. You may be able to stop the car at 60 mph in 200 feet; the 5er at 60 mph may take 1000 feet!

Actually a loaded semi can stop in less distance than an empty one.

A typical car takes about 300ft to stop at 80 MPH while a loaded semi at 55 takes about 300ft also. That does not include distance traveled while either driver is recognizing the hazard and the reaction time distance after a hazard is recognized.

I know I can stop my 5er at 60 in less than 300ft(a football field) also. 1000ft is over three football fields.

My truck and my 5er both have about the same weight on each brake. 2,000 on each trailer brake and about 2000 on each truck brake. So hooked or unhooked I am stopping the same weight per brake surface. In fact, with the 5er hooked up the rear truck tires have a better bite and will stop sooner.

Larryzv7 wrote:
Why do you think States, like California, have a maximum speed of 55-mph when towing? Someone told me that the tires on most trailers, including semi-trucks, are not made for speeds over 55-mph; is this correctincluding semi-trucks, are not made for speeds over 55-mph; is this correct?

That is not correct. Commercial truck tires are almost always rated for speeds up to 70 mph (depending on the tire diameter and width).

I have lived here in CA(spelled a "C" not a k) for most of my 77 years and early on thru the 50's, there were a lot of cars with mechanica brakes. That is most of the reason for the 55mph speed limit. I don't think that revenue is why we keep it, I think it is so ingrained in some folks that they still feel speed kills.

Raising the National limit to70 did not raise the number of accidents or fatal injuries and they feel it is a big lie and the real numbers are hidden.

The truth is 60 is in general a better limit for 4 wheeled vehicles towing and maybe even 6 wheeled wheeled vehicles than 55 because the improvement in the mechanical and electrical has made vehicles much safer and because the impatient drivers don't do as many stupid and unsafe moves when they get behind folks obseving the speed limit.

I really don't believe it is a great revenue generator.

Just my never to be humble oplniol.

That's baloney on truck tires. My 1100/22s are rated at 87 MPH with a full load. We run 75 MPH in western states and 80 in Texas. China Bombs, which I'd never run are dangerous sitting still. Blew one out at Bluewater Keys Fl on a 70 degree day sitting still. Started running Michelin LTs on it from then on. Why is the differential speed (not limit) on I 81 a problem? Because all the trucks run the L lane and 1 pulls out at 1 mi per hr faster and then they all slow down on a hill. I say make all trucks meet the speed limit or run the 2 lanes. It makes people mad when a truck swerves out to pass like that.

Studies have shown time and time again 2 speed limits are a bad idea. Then why do some states such as Ca have them? Simple answer: MONEY GENERATOR.

“I tried slower speeds to see better fuel economy but never felt safe.”

The GREAT excuse....others were going faster so I couldn’t comply with the law.