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Topic: Better tire than LT225/75R16? (Read 410 times) previous topic - next topic
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Better tire than LT225/75R16?
I broke the RF tire on the way into Big Bend National Park TX.  Sign said "Slow Bump Ahead".  I slowed down, went over it and sped back up.  That wasn't the bump they meant.  It felt sort of like the shocks bottomed out.    I stopped, looked and didn't see any damage.  Spent some days at Rio Grande Village, then wended my way along the Rio Grande to Presidio TX.   I noticed a vibration after that when I was hitting 60, which is my normal max.   I thought I'd done something to the front end, sought out a front end shop when I reached Las Cruces, NM and found Border International,  They could work on it on the next day, Christmas Eve.   At my request they aligned the front and rear ends.  The also found that the RF tire had broken cords and replaced it with a new Michelin LT225/75R16.

Jimmy Jones, the senior director at the location opined that Michelin LT225/75 R16 was marginal for a rig as heavy as the 31 IB. He said that the tire was good for 2500 lbs which was too close to the rig weight for comfort and recommended at least a 14 ply tire.  I told him the tires were approaching 5 years and I planned to replace them in 2020.   He opined that the '5 year' life span was a myth and that as long as the tire had good tread and no deterioration or checking it was good to go.  He also said to email him when I was ready to re-tire and he would give recommendations on what to get and where.

The LD seemed to be the smallest thing in the yard, with the next smallest being a dozen 44 passenger school buses in for maintenance during Christmas break. Maybe he had a different perspective.

What he said got me to thinking.  The 31 foot is heavy,  when I first had it home I weighed it full of gas & propane and dry water tanks.   It came in at 12,800.  It has always weighed 14,000+, even carrying just 10 gallons of water.  Are there other tires that would carry a heavier weight that would give me a better margin of error?

I just thought I would throw it out to the group.

Joel
Currently in Bisbee AZ,    heading indirectly to Q.
Joel & Terry Wiley
dog Zeke
2013  31 IB   Orwan   / 2011 CRV Tow'd LWEROVE

Re: Better tire than LT225/75R16?
Reply #1
Joel,
Thinking outside the box...
I'm relatively new to the land of E-450's.  The Ford van chassis has clearance limitations in wheel and tire sizes, not to mention the body of the Lazy Daze.  However, I have had five F250/350 trucks with a variety of slide-in campers on each.  The problem with truck campers is that they are very nearly ALWAYS OVERWEIGHT.  My last two rigs were outside the GVWR, but inside the combined axle weight limits.  The solution for truck campers is to increase the spring rate, use air bags, Helwig sway bars, stabiloads, and go to F and G rated truck tires and 5000lb wheels.

I'm not remotely interested in arguing the safety or responsibility of operating RV's beyond their GVWR.  It is simply a reality with truck campers and single rear wheel trucks.

Rickson wheels makes wheels for 3/4, 1 ton, and larger pickup trucks.  The wheels have a 5000lb load rating (unlike the stock 3500lb. rating) and sells F, G, and H rated commercial tires for them.  Most of the wheels are 19.5 inch and are made to fit various Ford bolt patterns. When I put these under my F350 carrying a 4000lb camper, it drove smoothly and was MUCH more stable than my correctly aligned and weighted Lazy Daze on the freeway.  The stock tires bulged and squooshed under the weight of the camper.  The Rickson wheel/tire combinations carried the load like a commercial truck and they wear like iron.

Rickson Wheel Manufacturing

Rickson makes DRW, as well as SRW models.  These wheel/tire combinations would certainly give you a greater load bearing capability.  I think the most likely difficulty would be whether the 19.5 wheel/tires would fit in the space in the chassis/body of the Lazy Daze.

I gave my camper to my daughter (who uses it on a 1 ton dually Chevy truck with 19.5 inch wheels and G rated tires).  I still have my F350 diesel with the 19.5's on it.  Without the camper, it has a terrible ride and feels like an unloaded dump truck going down the road without the weight of the camper to smooth the ride.  That might be what the ride of the Lazy Daze would feel like too?

How is that for outside the box?
Harold
2014 27 MB
Towd: Either the Jeep Wrangler or trailer containing the BMW R1200GS and 2 E-bicycles
Happy wife=Happy life

Re: Better tire than LT225/75R16?
Reply #2
Now that you have my interest, I nosed around the Rickson site and see that they carry a 17.5 inch 3750lb.  wheel and F and G rated tires for class C motorhomes.  Other than the cost, this might be a possible solution.

Harold
2014 27 MB
Towd: Either the Jeep Wrangler or trailer containing the BMW R1200GS and 2 E-bicycles
Happy wife=Happy life


Re: Better tire than LT225/75R16?
Reply #4
The LT225/75R16 load range E tire is rated at 2680 pounds each (not '2500'); the wheel (rim) is 16".  This wheel and tire sizes, axle ratings, front and rear end components, etc., on the E450 chassis are 'set' during manufacture; the settings include calculations of clearances between the rear duals. When a coach manufacturer builds a box on the E-450 chassis, clearances between the 'bottom' of the box and the tops of the rear dual tires is taken into account (one hopes); changing out a 16" wheel to a 17.5" wheel with significantly wider and 'taller' tires will not allow clearance between the duals, and very likely not between the box and the top of the tire.

One can check the specs on a variety of 'light truck' tires in the appropriate size for the E-450, i.e., LT225/75R/16, load range E on the Tire Rack site. If one's rig is 'heavy', one can lighten the load or perhaps consider a light truck tire with steel-belted sidewalls, i.e., a Michelin XPS Rib. (Not classified as an 'all-season' tire due to the tread pattern).

Link to Tire Rack's listings of tires in LT225/75R/16 load range E:

https://www.tirerack.com/tires/TireSearchResults.jsp?zip-code=95120&width=225/&ratio=75&diameter=16&rearWidth=255/&rearRatio=40&rearDiameter=17

2003 TK has a new home

Re: Better tire than LT225/75R16?
Reply #5

XPS Rib, as mentioned above, if you want something with a stiffer sidewall.

Some of the advice you were given by the tire 'pro' sounds like bad advice passed down through the generations.
 Car Talk: Why You Should Never Listen to Your Father When It Comes to Cars:...

This, I think, is a reliable source of information:
https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Tires_Brochure.pdf

Know your weights and adjust accordingly!

Rich
'03 MB in NC

As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
2003 MB

Re: Better tire than LT225/75R16?
Reply #6

Jimmy Jones, the senior director at the location opined that Michelin LT225/75 R16 was marginal for a rig as heavy as the 31 IB. He said that the tire was good for 2500 lbs which was too close to the rig weight for comfort and recommended at least a 14 ply tire.  I told him the tires were approaching 5 years and I planned to replace them in 2020.  He opined that the '5 year' life span was a myth and that as long as the tire had good tread and no deterioration or checking it was good to go.  He also said to email him when I was ready to re-tire and he would give recommendations on what to get and where.


Hmmmm imho everything in life ages.  I do agree five (5) years is arbitrary but (there is always a but) its a good place to start as most all folks are coming to the RV (read medium duty truck) from a light car world.  The 'rules' are different.   

There are laws that no amount of money can change -  the laws of physics apply no matter the belief system of the human. 

Good reference -----
Tires | NHTSA
personal fine art photo stuff
TF Mack | Flickr
It's all good .......
2014 Twin King

Re: Better tire than LT225/75R16?
Reply #7
The also found that the RF tire had broken cords and replaced it with a new Michelin LT225/75R16.


You mention total weight, but have you done 4 corner weight?  Are you running over weight on the RF, especially for your inflation?  You may need to shift loads around if you are unable to inflate adequately for the load on that corner.

Re: Better tire than LT225/75R16?
Reply #8
While I fully respect the opinions of the veterans on the forum, I still think there are other ways to think about Joel's question.
Regarding Joan's concerns about the diameter of the tire and the sectional width, here are the specifications for each tire:

Brand                    Michelin XPS 245/75-16             Goodyear G114
Wheel diameter    16 inches                                     17.5 inches
Load rating             E, 3042lb.                                      F, 3750/3525lb
Sectional width     9.6 inches                                      8.8 inches
diameter             30.6 inches                                      30.5 inches

As you can see, the tire diameter and the sectional width on the dual rear wheels does not appear to be a problem with the Rickson wheels yet the load capacity is much higher.  There may be other concerns with these tire/wheels on the Lazy Daze/E450 that should be addressed. The Rickson web page has interesting information and they have been doing this for a long time.
As an aside, I drove over 100K miles on my first set of G rated tires on the 19.5 Rickson rims on my F350 without a flat or anything else.  The tread still looked good, but  developed some cupping at around 5 years old.  I'm on a second set.  I have already blown an inside rear driver side tire on the Lazy Daze with less than 30K miles on the tire. The Michelin tires are good tires, but they are only E rated LT tires.
Harold
2014 27 MB
Towd: Either the Jeep Wrangler or trailer containing the BMW R1200GS and 2 E-bicycles
Happy wife=Happy life

Re: Better tire than LT225/75R16?
Reply #9
I would be remiss in not mentioning that the higher load rated tires are not well suited to soft substrate like sand.  The higher load rated tires don't deform against the ground so they don't give the large footprint that the E rated tires do. 
If Joel spends much time on sandy roads or beaches, the F rated tires won't be a good choice.
Harold
2014 27 MB
Towd: Either the Jeep Wrangler or trailer containing the BMW R1200GS and 2 E-bicycles
Happy wife=Happy life

Re: Better tire than LT225/75R16?
Reply #10
While a higher load range tire may be able to support more weight, one does need to heed the GAWR (gross axle weight rating) of each axle.  Just because a different set of tires (or rims) may be rated to support a higher weight, the chassis components are more likely the limiting factor.  This is also why it is important to get 4 corner weights as loaded for normal travel (including occupants and tank levels - and toad, if appropriate), and inflate all tires on an axle to the inflation appropriate for the heavier end plus a 5-10 psi safety factor if maximum inflation and rim limits permit.

Re: Better tire than LT225/75R16?
Reply #11
Thanks to all for the input.
First of all, but idea is to put a bit more space between current vs max tire rate for a little cushion. I have no intention of exceeding the GVWR. The rig blatantly violates a decades long rule of mine to never exceed 90% of capacity.
For the 31IB's 14500, that is 13,350.  When first weight (fuel, propane, no water) it came in at 12,660.  I don't recall if I was standing on the scale at the time, but that leaves a tentative CCC of 890.  I go about 210, the dogs about 26.  I did not deliberately downsize the dogs with that in mind, but they say if you mind the ounces, the pounds will take care of themselves. 
(Colin Fletcher The Thousand-Mile Summer)

This trip's latest visit to CAT scales was 13,180. The rear was 9,620. I'd filled 15 rather than the usual 10 gallons of water.  I shifted the beer forward.  I have yet to get a 4 wheel weight done.

Thanks again for all the input.  Even more opinions will be appreciated.
Joel
Bisbee was 16 last night and the RV exit ramp was an ice chute after the snow


Joel & Terry Wiley
dog Zeke
2013  31 IB   Orwan   / 2011 CRV Tow'd LWEROVE

Re: Better tire than LT225/75R16?
Reply #12
A friend of ours has s 31' IB and he had it weighed on the corners at an RV rally.  They recommended he buy F rated tires when he needed to replace the existing tires.
Ross Taylor
2017 MB

Re: Better tire than LT225/75R16?
Reply #13
"They recommended he buy F rated tires when he needed to replace the existing tires."
----
AFAIK, there are no F-rated 'light truck' tires in the OEM wheel size on the Ford E-450; 'E' load rated (10-ply) tires in LT225/75R/16 are what there is for 16" rims.

Harold posted information on Rickson 17.5" wheels/F-rated Goodyear tires; if one is seriously interested in the feasibility of changing out wheels to accommodate the higher-load rated tires, the websites Harold linked to might be a good place to start one's research.

It may well be that an F-rated tire would be a better choice for the heavy 30'/31' LD, but without wheel swaps, upfitting, and engineering calculations for fit/clearances and axle and other component stress (and given a hefty cash outlay for 6 wheels and F-rated tires if all the 'numbers' worked), it may be that getting the highest quality E-rated tires available and doing everything possible to keep the weight balanced and within limits (four-wheel weighing necessary) would be the way to go. 

As ever, YMMV.
2003 TK has a new home

Re: Better tire than LT225/75R16?
Reply #14
One other note ....
<smile> don't want to be that guy but ...... if you put bigger wheels on you LD your speedometer will show you going slower then actual speed......   soooooooo  unless you are using a GPS you will not be seeing the 'real' speed.    hmmmmm guess you'll get more time/miles  on your Ford E450 warranty.

glen
personal fine art photo stuff
TF Mack | Flickr
It's all good .......
2014 Twin King

 
Re: Better tire than LT225/75R16?
Reply #15
One other note ....
<smile> don't want to be that guy but ...... if you put bigger wheels on you LD your speedometer will show you going slower then actual speed......  soooooooo  unless you are using a GPS you will not be seeing the 'real' speed.    hmmmmm guess you'll get more time/miles  on your Ford E450 warranty.

glen
Tire diameter not wheel diameter is what can affect your speedometer's accuracy. Just say'n.  ;) 

Charles
Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King