Interstate speeds

[halliday]

I am running a Cherokee 275 fiver behind a Dodge 2500 6.7L Diesel. The fiver is an 08 with the original tires. They have 4 trips from Nova Scotia to Florida and 2 trips NS to Ontario. So a total of about 30K miles on the tires. They are showing some wear, but no cracks, nothing serious all normal. After reading all the horror stories on here I have been pretty good at checking tire pressures and running 60-65, with the odd excursion to 70 or so on the insanity trhat is the I495 around Boston and the I495 around DC. Anyway long weekend in October (Thanksgiving or Columbus depending what side of 49th), we were going to Hamilton, ON to see the Boy. We pushed a little later than planned, so I thought I would try and make some time up. We're travelling through the Canadian part of the Appilacians I let her run up to 70+ going down hill and could keep it above 60 going up hill with no downshift...sweet...until we hear a loud POP. Wifey says what's that..I say..tire!. I pull over and stop. Sure enough the hind tire pax side was blown. Minimal damage. Changed the tire and on our way. Now I had no spare, so I ran at 60 the rest of the way up and back to NS almost 3000 kms with no further problems. This was with the 3 old tires and the never been used spare. I had planned to change the tires this winter anyway.
The point of this rambling is that the bad press these tires get is more the fact they are being driving too fast than any defects in the tires.
Driving at 60 mph is something like an old Squadron CO said to me once regarding my monthly Bar Bill maximum...it's a LIMIT NOT a TARGET!

The story of the tire change will be saved for around the campfire somewhere in South Florida looking for the real Red SOX in spring training next year.

[rotorhead1250]

Very interesting conversation. I also have the greenball tires in 14 inch on my greywolf and also ‘thought’ max was 65mph. I didn’t realize that they had an L rating (which is 75). I still tow about 65 but drive by foot here in New Mexico so I can take advantage of downhill momentum for the uphill climb. I’m not nervous but do would watch the speedo so as not to go too fast.

[Herk7769]

Appears Greenball ST tires are the exception to the rule.

There always is one; I just never saw it in print before.
The link posted by Transamz9 is the "Rule" I was talking about and it is also backed up by the RV Safety & Education Foundation 321-453-7673
Fax 321-453-3853

[jeeplj8]

Originally Posted by herk7769

Appears Greenball ST tires are the exception to the rule.

There always is one; I just never saw it in print before.
The link posted by Transamz9 is the "Rule" I was talking about and it is also backed up by the RV Safety & Education Foundation 321-453-7673
Fax 321-453-3853

many years ago LT tires did not carry speed ratings period, and the "official" limit was something low - but then manufacturers started putting speed codes on them and now many are rated at 99mph, because you need that in a LT tire...

Anyway - no offense, I just don't trust anything that I see that suggests there is uniform standard for something. I tend to put more credit in what specific manufacturers say.

The real problem for the RV owner is that they need to find out the specific information for THEIR equipment.

[huizarr]

I realize the last comment in this thread was a week ago. But I have to ask, isn't the trouble with the trailer tire the fact that they are usually run at near full load rating? Say you have a Pop-up with 2 tires rated to carry 1760# (ST205/75R14 LRC) each. This gives a total axle weight rating of just over 3500#. The GVW of a Rockwood HW276 is 3766#, deduct 10% for hitch weight and you are at 3389#, that is only 111# from the maximum tire rating.

I have read that for each 10mph over 65mph you have to deduct 10% off the load rating. So if you pull the HW276 at 75MPH, you have an effctive load rating of 3150#, now you have overloaded your tires.

As for us we have a HW296 (GVW of 4201) and run 4 ST205/75R15 LRC with the load rating of 1760. This gives us a max load on the tires of over 7000#, so we could easily run 75 MPH down the highway. My issue with that is the MPG. Last year we went from San Antonio, TX to Orlando, FL. On the way down we were going about 69 MPH and got about 12.9 MPG, on the way back I slowed to 65MPH and the gas milage increased to 13.3 MPG. I have run several other trips usually around 65MPH and get in the low 13s MPG. Unless we are in a hurry I keep it at 65 even though I have the luxury of going faster.

[acadianbob]

Well, maybe you can technically tow at 75mph, but, I question the safety of doing so.

[whj77372]

The tires that came on my 2012 V-Cross 275 fiver are ST with D rating and they are rated at 65 MPH. Many Interstates have a minimum speed of 45 MPH, recently I learned that MI has a minimum speed of 55 MPH on Interstates?

[whj77372]

We have a new toll road in Texas that opened today. It goes from San Antonio to Austin and the speed limit is 85 MPH. I wonder if they allow RVs on the toll way?
The toll road is owned by a company from Spain which has leased the rights to the road and of course the tolls. Texas is selling off what I would consider assets to the highest bidder no matter were they are from.

[Len & Cheri]

Originally Posted by whj77372

We have a new toll road in Texas that opened today. It goes from San Antonio to Austin and the speed limit is 85 MPH. I wonder if they allow RVs on the toll way?
The toll road is owned by a company from Spain which has leased the rights to the road and of course the tolls. Texas is selling off what I would consider assets to the highest bidder no matter were they are from.

I'd heard that the company paid for the road and in return they collect the tolls. Is that not right?

[jeeplj8]

Originally Posted by whj77372

The tires that came on my 2012 V-Cross 275 fiver are ST with D rating and they are rated at 65 MPH. Many Interstates have a minimum speed of 45 MPH, recently I learned that MI has a minimum speed of 55 MPH on Interstates?

A general rule of thumb is that the minimum is 20 mph less than the maximum.