Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 

Go Back   Keystone RV Forums > Keystone Fleet | Keystone RV Models > Travel Trailers
Click Here to Login

Reply
 
Thread Tools Display Modes
 
Old 04-29-2021, 07:43 PM   #21
sourdough
Site Team
 
Join Date: Feb 2014
Location: W. Texas
Posts: 17,660
Quote:
Originally Posted by Tireman9 View Post
As an actual Tire Design Engineer I can assure you that there is more misinformation or partially correct information out there than technically accurate information.

It is true that the original tire selection is the responsibility of the RV Mfg. The issue is that once the RV is sold it seems that most RV Manufacturers have little or no interest in standing behind their choices with any actual warranty service when it comes to tires.


It seems that OE tire selection for RVs is based on one goal. Find the smallest, lowest cost tire that will meet the requirements.


The only Federal (DOT) requirement is that the tire load capacity be AT LEAST equal to the maximum load rating of the axle. While RVIA now requires 10% extra capacity, DOT does not. As a point of reference most cars come with a 20% to 30% or higher Reserve Load capacity



A smaller tire can mean the RV Manufacturer can get away with less costly (smaller) wheel well so this is extra pressure on purchasing to get the minimum possible tire that can meet the requirements.


Given the above, it is up to you, the owner, to decide if you want any, some or more "Reserve Load capacity" for your RV. You may have the option of larger tires or you may be restricted to trying to find tires of the same dimensions but with higher load capacity.


You need to educate yourself about the requirements and limitations of the four "types" of tires that are in the market. 'P" is Passenger type. If used on an RV (trailer or motorhome) the load capacity Must be reduced by dividing by 1.1 but not everyone will know or do that. LT type can be used in RV service but you will soon discover that LT tires with the same dimensions and Load Range (ply rating) have a lower load capacity than the same dimension ST type.
ST type have the highest load capacity rating for a given set of dimensions, but you need to remember that the ST tire Load formula that is used to calculate the tire load capacity is based on an assumption of a 65 MPH Max speed. We all know that there is "No Free Lunch" and the trade-off for increased load capacity is lower speed capability. The "Speed Rating" symbol on many ST type tires is based on a 30 minute test so you need to decide if you want to depend on such a short term test when making a tire selection.
Finally there are actual "Truck / Bus" tires. These have no leading letter and are usually on 17.5" or larger wheels. These tires have higher Load Range, usually F or higher These tires are almost all rated for 75 MPH in RV use on the highway.


Do your homework. Ask questions, but remember there are very few really knowledgeable people out there who have the training or experience in tire engineering. Just having driven on tires for 40 years is not the same as having been held responsible for designing tires for Truck, Passenger, Trailer, or Indianapolis racing application. Also, being able to read Federal Regulations is not the same as having to work within those regulations while meeting the goals and demands from GM, Mazda, Toyota, Honda, Freightliner, MB, Nissan, Ford, or Chrysler.

Roger is there some reason you upsized the fonts for your post (shouting?)? We all use regular fonts and the community rules have guidelines on them - you might read those. Everyone's thoughts/opinions carry the same weight upsized fonts or not.
__________________
Danny and Susan, wife of 56 years
2019 Ram 3500 Laramie CC SWB SB 6.4 4x4 4.10
2020 Montana High Country 331RL
sourdough is offline   Reply With Quote
Old 04-29-2021, 08:55 PM   #22
JRTJH
Site Team
 
JRTJH's Avatar
 
Join Date: Mar 2011
Location: Gaylord
Posts: 26,974
Quote:
Originally Posted by fjr1300 View Post
Recstuff.com has four styles of 15" 6 lug wheels rated for 3200 lbs.
Thanks for the info... I went to recstuff.com and sure enough... Those are Sendel wheels, also listed on their website... Easy, right ??? NOPE !!! I used the Sendel part number, and looked them up on the Discount Tire site. Same model/part number is listed for the same price, $119 each, but on the DT site, those wheels are rated at 2830/80PSI... I sent an email to DT asking if their specs are correct, so we'll see.... Tomorrow, I'll check with Sendel to get their specs as well.

Anyway, thanks again for the link. Hopefully it'll lead to an answer....
__________________
John



2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS
JRTJH is offline   Reply With Quote
Old 04-30-2021, 12:06 AM   #23
CWtheMan
Senior Member
 
CWtheMan's Avatar
 
Join Date: Feb 2010
Location: Taylors, SC
Posts: 3,031
Quote:
Originally Posted by JRTJH View Post
I haven't been able to find wheels rated at 3080 pounds that are 15" 6 lug. Do you know of any?
They can be found somewhere on this page.

https://www.carlislebrandtires.com/o...trailer-wheel/
CWtheMan is offline   Reply With Quote
Old 04-30-2021, 01:09 AM   #24
CWtheMan
Senior Member
 
CWtheMan's Avatar
 
Join Date: Feb 2010
Location: Taylors, SC
Posts: 3,031
Being an expert on how tires are built does not indicate expertise on how tires are governed or how those regulations are linked together with tire industry standards.

The National Highway Traffic Safety Administration (NHTSA) is the arm of the DOT that establishes vehicle safety standards, including tires. They are numerous standards controlled by NHTSA. They established the Federal Motor Vehicle Safety Standards (FMVSS) to insure minimum tire standards are observed. They also administer the documents in SAFECAR.

NHTSA uses mandatory mandates to insure consumers are aware of important tire industry standards that are spelled-out in various FMVSS standards. The following paragraph is a mandated mandatory safety notation about tire designated sizes. It is found in all vehicle owner manuals. If you look at the USTMA industry standards for replacement tires you will also find that statement.

Tire Size: “To maintain tire safety, purchase new tires that are the same size as the vehicle’s original tires or another size recommended by the manufacturer. Look at the Tire and Loading Information label, or the sidewall of the tire you are replacing to find this information. If you have any doubt about the correct size to choose, consult with the tire dealer”.

The ST tire manufacturers have acted quite favorable to the needs of load capacity reserves for RV trailer tire fitments with the addition of load ranges with higher PSI ratings for more load capacity within a designate tire size; Such as the ST25/75R15 having load range letters C, D, E, and F.
CWtheMan is offline   Reply With Quote
Old 04-30-2021, 03:49 AM   #25
flybouy
Site Team
 
Join Date: Oct 2011
Location: Joppa, MD
Posts: 11,739
Quote:
Originally Posted by JRTJH View Post
Thanks for the info... I went to recstuff.com and sure enough... Those are Sendel wheels, also listed on their website... Easy, right ??? NOPE !!! I used the Sendel part number, and looked them up on the Discount Tire site. Same model/part number is listed for the same price, $119 each, but on the DT site, those wheels are rated at 2830/80PSI... I sent an email to DT asking if their specs are correct, so we'll see.... Tomorrow, I'll check with Sendel to get their specs as well.

Anyway, thanks again for the link. Hopefully it'll lead to an answer....
I looked at the Sendel site and now they list 2 rims in the style I have with 2 weight and psi ratings and different part numbers. http://sendelwheel.com/wheels/t03sm.html. For me it's academic because I don't need the extra capacity.
__________________
Marshall
2012 Laredo 303 TG
2010 F250 LT Super Cab, long bed, 4X4, 6.4 Turbo Diesel
flybouy is online now   Reply With Quote
Old 05-23-2021, 08:05 AM   #26
lcarver02
Member
 
Join Date: Jul 2017
Location: Pleasantview
Posts: 72
You can buy some very good quality American made trailer tires with high weight ratings for half the cost. No reason to go to the Michelin your thinking of (assuming load rage e). Goodyear Assurance is a very good one. Suggest a Load Range E at least 117 rated and a speed rating of N or R (depends on how fast you drive). Air them to Maximum pressure - This is a Must.
lcarver02 is offline   Reply With Quote
Old 05-23-2021, 08:31 AM   #27
lcarver02
Member
 
Join Date: Jul 2017
Location: Pleasantview
Posts: 72
Quote:
Originally Posted by lcarver02 View Post
You can buy some very good quality American made trailer tires with high weight ratings for half the cost. No reason to go to the Michelin your thinking of (assuming load rage e). Goodyear Assurance is a very good one. Suggest a Load Range E at least 117 rated and a speed rating of N or R (depends on how fast you drive). Air them to Maximum pressure - This is a Must.
Correction, not Goodyear Assurance, it is Goodyear Endurance. They are excellent tires.
lcarver02 is offline   Reply With Quote
Reply

Tags
tires, travel trailer

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
Forum Jump

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by the Keystone RV Company or any of its affiliates in any way. Keystone RV® is a registered trademark of the Keystone RV Company.


All times are GMT -8. The time now is 06:12 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.