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

Go Back   iRV2 Forums > THE OWNER'S CORNER FORUMS > Monaco Owner's Forum
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 12-11-2009, 09:27 AM   #1
Senior Member
 
jeepsrule's Avatar
 
Grand Design Owners Club
Join Date: Nov 2009
Posts: 394
Tire Size Question

My coach has the original tires on the back Goodyear 670 RV size 275/70R 22.5 (sidewall coded 1305). The previous owner replaced the front tires last year with G169RSA size 255/70R 22.5 (sidewall coded 4808). What problems will this change in size cause and when I replace the rears should I stick with the manufacturers recommended size 275/70R and eventually replace the fronts with that too?
__________________
2022 Grand Design Reflection 337RLS 5th wheel / Ford F-350 Lariat 6.7L Diesel.😎
Randy & Pam
jeepsrule is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 12-11-2009, 09:39 AM   #2
Senior Member
 
Gordon66's Avatar
 
Monaco Owners Club
Thor Owners Club
Ford Super Duty Owner
Join Date: Dec 2006
Location: Victoria, Texas
Posts: 248
I would stay with the 275's. The load capacity is higher on the 275's. See the attached chart.http://www.goodyear.com/rv/pdf/rv_inflation.pdf
__________________
Larry & Doni
2015 Four Winds 31W E-450
South Texas Renegades FMCA F376075
Gordon66 is offline   Reply With Quote
Old 12-11-2009, 09:56 AM   #3
Senior Member
 
jeepsrule's Avatar
 
Grand Design Owners Club
Join Date: Nov 2009
Posts: 394
Will having these mixed tire sizes cause me any headaches?
__________________
2022 Grand Design Reflection 337RLS 5th wheel / Ford F-350 Lariat 6.7L Diesel.😎
Randy & Pam
jeepsrule is offline   Reply With Quote
Old 12-11-2009, 10:10 AM   #4
Senior Member
 
jeepsrule's Avatar
 
Grand Design Owners Club
Join Date: Nov 2009
Posts: 394
As I consider tires for the rear I've heard good things about the Michelin tires or would you stick with Goodyear?
__________________
2022 Grand Design Reflection 337RLS 5th wheel / Ford F-350 Lariat 6.7L Diesel.😎
Randy & Pam
jeepsrule is offline   Reply With Quote
Old 12-11-2009, 10:48 AM   #5
Registered User
 
Join Date: Aug 2009
Posts: 256
I would have the front of the coach weighed as the 255/70 does not have enough cargo carrying capacity 11,020 to match the axle rating of 13,000 lbs. (even at the 120 max pressure)

As far as brands, you hear good and bad about both Goodyear and Michelin. Personally, I've never had a problem with either one.
Mandys Man is offline   Reply With Quote
Old 12-11-2009, 04:24 PM   #6
Senior Member
 
Steve Ownby's Avatar
 
Join Date: Nov 2008
Location: Cosby, Tn
Posts: 6,587
You have a coach with a safety issue! Your coach has a 13000# front axle and your current front tires have a max capacity almost 2000# less than that. I doubt you have that type of under weight on your front axle. Do not take the chance. Put 275's on your coach without delay. Front tire blow-outs can be catastrophic. At the very least, go to the nearest truck stop or anywhere else you can weigh your front & see for yourself what your needs are.

Steve O
__________________
Steve Ownby
Full time since 2007
2003 Monaco Signature
Steve Ownby is offline   Reply With Quote
Old 12-15-2009, 06:55 AM   #7
Senior Member
 
Mutt's Avatar
 
Monaco Owners Club
Join Date: Aug 2009
Posts: 465
You definitely need to have your coach weighed on both axles to ensure there is not a safety issue due to overloading. And a better insurance would be to have a four corner weight to get each tire. Your rear tires should be good for two more years, assuming not exterior sidewall cracks are evident. But, when you are looking for tires, I might suggest the Continential HSR1. It comes in the 275-70x22.5 size. I replaced all six last summer, and have driven them almost 7,000 miles. They ride good on my 02' unit. Price was under $400 each OTD( I believe they have come down in price since last summer due to the state of the economy). They took less weight per tire than previous Goodyears during balancing. And according to the tire casing, they were manufactured in the USA. Just a thought.
David
__________________
2002 Monaco Diplomat Triple Slide PST
2011 Buick Enclave(AWD);
1970 Home built 11.5 ft Slide-in Cabover
Mutt is offline   Reply With Quote
Old 12-16-2009, 05:59 AM   #8
Senior Member
 
jeepsrule's Avatar
 
Grand Design Owners Club
Join Date: Nov 2009
Posts: 394
Quote:
Originally Posted by Mutt View Post
You definitely need to have your coach weighed on both axles to ensure there is not a safety issue due to overloading. And a better insurance would be to have a four corner weight to get each tire. Your rear tires should be good for two more years, assuming not exterior sidewall cracks are evident. But, when you are looking for tires, I might suggest the Continential HSR1. It comes in the 275-70x22.5 size. I replaced all six last summer, and have driven them almost 7,000 miles. They ride good on my 02' unit. Price was under $400 each OTD( I believe they have come down in price since last summer due to the state of the economy). They took less weight per tire than previous Goodyears during balancing. And according to the tire casing, they were manufactured in the USA. Just a thought.
David
thanks I'll look into the Continental Tires.
__________________
2022 Grand Design Reflection 337RLS 5th wheel / Ford F-350 Lariat 6.7L Diesel.😎
Randy & Pam
jeepsrule is offline   Reply With Quote
Old 12-16-2009, 04:59 PM   #9
Senior Member
 
Bonanza's Avatar
 
Entegra Owners Club
Join Date: Nov 2009
Location: Christoval, Texas
Posts: 153
I just recently replaced my 4 rear tires on my 2004 Diplomat and did a ton of research before doing so. I posted for tires on two forums and got alot of great information, however after much research and debate I chose to go back with what Monaco had put on in the first place being how the original tires lasted 65,000 miles and really did not look like they needed replacing they were just according to the date on the tire dated out about 6 years old and I wanted to be safe. You will hear good and bad things about both Michelin and Goodyear as stated by Mandys Man I figured if the Goodyear gave that good of service in 65,000 miles, what the heck. I would however stick with the 275 and when I bought mine about 2 months ago they were having a great sale on them plus they are all position tires. Hope this helps.
__________________
David & Rhonda
2017 Holiday Rambler Vacationer XE 32A
2009 Smart Car
Bonanza is offline   Reply With Quote
Old 12-16-2009, 10:51 PM   #10
Senior Member
 
Drifter's Avatar
 
Monaco Owners Club
Holiday Rambler Owners Club
Join Date: Dec 2006
Posts: 1,723
I talked to a guy this past summer with a 2001 Diplomat that up sized his tires to 295's, the ride was much better and the load rating was much higher. I think they were a off brand something like Kumho.
__________________
Mike & Sharon and our Pup Frankie
2008 HR Endeavor 40PDQ

Drifter is offline   Reply With Quote
Old 12-18-2009, 09:34 PM   #11
Senior Member
 
jacmat's Avatar
 
Monaco Owners Club
Join Date: Jun 2008
Location: Quebec, Canada
Posts: 168
Quote:
Originally Posted by Drifter View Post
I talked to a guy this past summer with a 2001 Diplomat that up sized his tires to 295's, the ride was much better and the load rating was much higher. I think they were a off brand something like Kumho.
This is something I plan to do next year, replacing my front 275 with the 295. I think with the 295 you can reduce air pressure, thus improving ride.

One question though, will that affect the speedometer, is it measured with the front wheels or the rear wheels.
__________________
Monaco Diplomat
jacmat is offline   Reply With Quote
Old 12-19-2009, 03:16 PM   #12
Senior Member
 
rvtips's Avatar
 
Monaco Owners Club
Join Date: Jan 2006
Location: Martinez,CA
Posts: 720
Will changing to 295 still give you enough room?


Quote:
Originally Posted by jacmat View Post
This is something I plan to do next year, replacing my front 275 with the 295. I think with the 295 you can reduce air pressure, thus improving ride.

One question though, will that affect the speedometer, is it measured with the front wheels or the rear wheels.
__________________
Our Rig
Phil and Joyce 2003 Safari Sahara.
2010 Honda CR-V Same color as the MOHO
rvtips is offline   Reply With Quote
Old 12-19-2009, 07:39 PM   #13
Senior Member
 
jeepsrule's Avatar
 
Grand Design Owners Club
Join Date: Nov 2009
Posts: 394
Quote:
Originally Posted by jacmat View Post
This is something I plan to do next year, replacing my front 275 with the 295. I think with the 295 you can reduce air pressure, thus improving ride.

One question though, will that affect the speedometer, is it measured with the front wheels or the rear wheels.
If my coach were loaded to the max with 275 tires I would have tire pressure at 115 psi in the front tires, if I went up to 295 size tires I could lower pressure by 15 psi. How much would 100 psi compared to 115 change the ride??
__________________
2022 Grand Design Reflection 337RLS 5th wheel / Ford F-350 Lariat 6.7L Diesel.😎
Randy & Pam
jeepsrule is offline   Reply With Quote
Old 12-20-2009, 07:59 AM   #14
Senior Member
 
walt2137's Avatar
 
Monaco Owners Club
Join Date: Sep 2003
Location: Quitman MS
Posts: 2,967
Quote:
Originally Posted by jeepsrule View Post
If my coach were loaded to the max with 275 tires I would have tire pressure at 115 psi in the front tires, if I went up to 295 size tires I could lower pressure by 15 psi. How much would 100 psi compared to 115 change the ride??
In my opinion you could not feel it, I agree the 255 on the front of your coach are probably over loaded you need to weigh your coach. Here is a good post from another forum on air pressure in tires and the guy that posted this is very knowledgeable on the RV and heavy duty trucks. Your rear tires are not quite 5 yrs old, if it was me I would worry about the front tires and dont give them away I have always got at least $100 for 7 yr old tires.

Walt

A lot of folks strive to go to heavier tires so they can run less air
pressure. Low pressure is the most common cause of tire failure and wear, as you
know. If one can feel a difference in ride running 10 lbs less air they
either have a problem with the suspension system or are sitting on a box to
drive. Going to a heavier tire is in most cases a good idea, it should not
be to run less air. Tires run cooler with more air, less rolling resistance,
less wear and if they lose a little air it is not under inflated. Most
folks have stepped up the air pressure in the front by 10lbs with GY tires,
this is a good idea. As others have stated some like to run 75, 80 or 85 lbs
in the tag tires because the chart says it is okay... If they would run
100lbs in the tag tires the tires are a lot happier. Michelin will tell you
flat out nothing below 85, but if you talk to their engineers, they are hard
to find, they are not the road reps, they will tell you more is better.
Think about it, if you go from 100 to 110 it is a 10% difference. After
suspension, etc 10% would be really hard to feel, if it can be felt something
else is wrong and they are asking the tires to be the suspension system. I
really think one who runs less air and says it rides better just want it to
feel that way so they believe it. Low air pressure causes a lot of squirm in
the tire itself, working or flexing between the plys and structure of the
tire, this causes ply separation, heat and other issues. . A round object
rolls better, ever try to roll a egg? As I have said before fleets typically
run 110 in the steers and 100 in all duals, Tractor trailers as a fleet
travel further in a day than all the motorhomes as a fleet do in a year. the
motorhome fleet is a very small mileage group. Fleets are managed by folks
that look to reduce cost per mile and have engineers, routers, etc to keep
costs and downtime down. We do not need to try to reinvent the wheel, they do
a good job if it. We can learn a lot from them they can do more testing in
a day of their fleet than one of us can in a lifetime.

Now think about this a tractor trailer is limited to 32,000 lbs per tandem
divide that by 8 and they run 4,000 lbs per tire. On spread axle trailers
the limit is 20,000 per axle, they run 100 with a 5,000 lb load. On The
steer axle is limited to 12K in most cases that equals 6,000 per tire. Now a
lot of coaches are at or above 20,000 on the drive axle which is the limit
for the roads (ask Ohio), that is 5,000 per tire. If 100 lbs is good for
them at 4,000 per tire on the drives or 5,000 on spreads. They have
seriously different tire loading and do not adjust their air pressure with every
loading or unloading. The average fleet truck weighs about 33,000 lbs
empty. Fleets strive to be able to scale 47,000 lbs, (80,000 gross loaded) as
they get paid by the pound.

Your comment about rolling resistance is true, if you have see the videos
of a tire going down the road with difference air pressure you will see the
difference. As the air pressure goes down the hump in the front of the tire
gets bigger, a lot like the water the bow of a boat pushes ahead of it
when it is running. This hump or wad increases rolling resistance and causes a
tremendous amount if flex in the tire, flex translates in to heat. As we
have all seen when someone tries to set a mileage record, college contests,
engineering contests, etc, they all run the smallest tire possible inflated
as much as possible.
__________________
Walt & Will
2000 Dynasty
2017 Ram Big Horn Crew C 4X4 w/ M&G
walt2137 is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Ambassador Storage Bay Size Question Rockhouse Monaco Owner's Forum 3 11-01-2009 05:50 PM
Solar wire size & amps question hdossett RV Systems & Appliances 2 10-14-2009 07:26 PM
Bounder: Tire size? vman60 Fleetwood Owner's Forum 4 09-07-2009 04:34 PM
Original tire size for an '86 Elandan? padraig1066 Winnebago Industries Owner's Forum 2 08-25-2009 01:29 PM
Tire cover question Indy Itasca Winnebago Industries Owner's Forum 5 05-13-2007 04:49 PM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 01:57 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.