Reply
 
Thread Tools Display Modes
Old 10-23-2013, 04:29 PM   #1
Commercial Member
 
Join Date: Jul 2013
Location: Akron, Ohio
Posts: 1,145
Braking News- Max Speed on ST type tires

Finally chased down the answer. Getting to the bottom was a challenge because I ran into "customer service" people who could read from a script but had no idea why they were giving me the answer they were.

Even got to the engineers at Tire & Rim Association and based on their answers it was obvious they had not thought about ST type tires or the unique nature of RV application so acted a little surprised when I identified the engineering analysis that indicated that the current loads too high for many trailers and that the load capacity should be decreased by 15% or more.

Anyway here is the bottom line.

For Goodyear Marathon tires only:
There is a Tech bulletin PSB#2011-13 that uses information from TRA (blind leading the unknowing in my opinion but they are the ones that have to stand behind their warranty).
The tech bulletin says that the normal max speed for Marathon ST type tires is 65 mph. This speed can be increased up to 75 only if the inflation pressure is increased by 10 psi.
Goodyear does not support or condone operation above 75 at any time.
The trailer owner is responsible to confirm the rim is rated for the new inflation level.
While TRA indicates a further increase in speed might be achieved Goodyear has decided not to adopt this option.

The person I talked with at Tire Rack said they had already changed their web site to indicate this applied to Goodyear tires only and that they were attempting to learn if any other ST tire manufacturers were willing to make a similar change. As of Saturday Oct 19 they had not identified any other tire manufacturer willing to make such a change.
__________________

__________________
.
I write a blog on RV tire application and safety and give seminars on tires at RV events across the US. 40 years experience as tire design & quality engineer for major tire mfg. Freelander 23QB on Chevy chassis is my RV
RV Tire Safety Blog
Tireman9 is offline   Reply With Quote
Old 10-23-2013, 04:37 PM   #2
Wanna Be Camper
 
SaskCampers's Avatar
 
Join Date: Mar 2010
Location: Moose Jaw, Saskatchewan
Posts: 2,370
Thanks for the info and taking the time to track it down.
__________________

__________________

John & Deb
2011 F250 Lariat FX4 Crew Cab 6.2
2011 Flagstaff V-Lite 30WRLS
Days Camped 2016: 3 2017: 0
SaskCampers is offline   Reply With Quote
Old 10-23-2013, 04:45 PM   #3
Fulltime family RVer
 
ependydad's Avatar
 
Join Date: Nov 2011
Posts: 14,769
Any chance you can track down/confirm this response from Maxxis?

any experience with taskmaster radial flyer trailer tires?
__________________
2012 Ram 3500 DRW/crew cab/long bed/4x4/4.10 gears pulling an early 2013 Sabre 36QBOK
Checkout my site for RVing tips, tricks, and info | My family and I have fulltimed since June 2015
ependydad is offline   Reply With Quote
Old 10-23-2013, 04:57 PM   #4
H2oski
 
Join Date: Dec 2008
Location: Hartford, AL
Posts: 637
Quote:
Originally Posted by ependydad View Post
Any chance you can track down/confirm this response from Maxxis?

any experience with taskmaster radial flyer trailer tires?
Check this

http://www.maxxis.com/Repository/Files/m8008load.pdf
__________________
Wife
2007 Chevy 2500 HD 6.6
2012 Sabre 31RETS
(LA) Lower Alabama
h20ski is offline   Reply With Quote
Old 10-23-2013, 05:03 PM   #5
Fulltime family RVer
 
ependydad's Avatar
 
Join Date: Nov 2011
Posts: 14,769
Quote:
Originally Posted by h20ski View Post
Yeah, I've seen that. But wmtire somehow emailed them directly and got the more lengthy response indicating similar to good year- with a air pressure increase, you can increase the speed. I wasn't sure if Tireman could confirm that same response.

Not that I have a pressing need to go over 65mph. I'm almost exclusively a 62mph cruise control kind of guy. Just curious.
__________________
2012 Ram 3500 DRW/crew cab/long bed/4x4/4.10 gears pulling an early 2013 Sabre 36QBOK
Checkout my site for RVing tips, tricks, and info | My family and I have fulltimed since June 2015
ependydad is offline   Reply With Quote
Old 10-24-2013, 06:19 AM   #6
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 21,169
The max is "up to" 10 PSI over the "pressure required for the actual tire load" taken from the charts.

If the tire is already at its max load at its max sidewall pressure, no further increase in pressure is allowed and speed rating is then 65 MPH.
__________________

Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW
Herk7769 is offline   Reply With Quote
Old 10-24-2013, 07:29 AM   #7
Senior Member
 
Join Date: Jul 2010
Location: Waynesville
Posts: 12,027
If you want too really get (Confused) set your (Cold Max Air Pressure) early in the AM. Now travel with the SUN on one side for a period of time.Now look at your (TPMS)! Should we stop and release some PSI on the Sunny side? or turn around and drive the otherway until the PSI is the same in all Tires? Stop and park in the shade? Now OnStar gives a alert that the Truck tires are (Low PSI) on one side also! There is (Air) in the truck tires,and (Nitrogen) in the trailer tires? What a Dilemma! Youroo!!
__________________
youroo is offline   Reply With Quote
Old 10-24-2013, 08:15 AM   #8
Mod free 5er
 
Join Date: Mar 2008
Location: Concord, NC
Posts: 24,215
Quote:
Originally Posted by youroo View Post
If you want too really get (Confused) set your (Cold Max Air Pressure) early in the AM. Now travel with the SUN on one side for a period of time.Now look at your (TPMS)! Should we stop and release some PSI on the Sunny side? or turn around and drive the otherway until the PSI is the same in all Tires? Stop and park in the shade? Now OnStar gives a alert that the Truck tires are (Low PSI) on one side also! There is (Air) in the truck tires,and (Nitrogen) in the trailer tires? What a Dilemma! Youroo!!
The first time our "over pressure" alarm went off on our way from Daytona to Orlando in Jul 12, it scared the cra- out of us. Couldn't read the little icon on the monitor, so luckily we were at the entrance to a rest area and pulled in. Did the normal, walk the dog, rest room visits, etc and in the 15 minutes or so time, the tires cooled off and the alarm went off. Finally found the manual and verified it was a high pressure alarm. Sat for another 15 -20 minutes and then took off. Pressure had gone down about 2# and stayed there. The outside temp increased, but the tire pressure stayed constant. 2nd time was coming home from FL in Mar and we just pulled into the first rest area and took a break. Now, when the pressure gets close, we just take a break and let the tires cool. What's funny is once they cool, they seem to stabilize on pressure. Always start off with 65# cold.
__________________
OldCoot is offline   Reply With Quote
Old 10-24-2013, 08:42 AM   #9
Senior Member
 
Join Date: Nov 2012
Location: X
Posts: 2,781
Quote:
Originally Posted by herk7769 View Post
...
If the tire is already at its max load at its max sidewall pressure, no further increase in pressure is allowed and speed rating is then 65 MPH.
I don't think we know that for sure based on earlier posts. That is the big question.
__________________
BarryD0706 is offline   Reply With Quote
Old 10-24-2013, 09:03 AM   #10
Mod free 5er
 
Join Date: Mar 2008
Location: Concord, NC
Posts: 24,215
Quote:
Originally Posted by BarryD0706 View Post
I don't think we know that for sure based on earlier posts. That is the big question.
I think what Herk posted is pretty clear. If at max load, max cold pressure, max speed is 65, no ifs, buts or ?
__________________

__________________
OldCoot is offline   Reply With Quote
Reply

Tags
tire, tires

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



» Virginia Campgrounds

Reviews provided by




ForestRiverForums.com is not in any way associated with Forest River, Inc. or its associated RV manufacturing divisions.


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 02:30 AM.