tire info

[dongw]

I know there's been a number of posts about tires on here, but need info on what brands of tires are good and which are not, also comments on using steering tires on the dual rear wheels as opposed to drive tires. also does anyone have the specs on Sumitomo ST719 tires for 19.5 inch rims? Thread depth, speed rating, load index, service rating?


thanks..

[92landyacht]

Really comes down to how much you're willing to spend. In my opinion, once you get out of the high end tires like Michelin, their all pretty much the same. I use the Samson GL283A tires on my 1992 36' Land Yacht. Plenty deep tread and good 12 ply construction. Their usable for both steer wheels and drive wheels. With 9 tires (including the spare) cost was critical to me. Driven quite a few miles on them and they seem to perform quite nicely. Many of the long haul truckers I found use Samson Tires but other brands in the same price range seem to have similar characteristics.



By the way, the last time I purchased a time I picked it up from a company called Simple Tire and it cost me $139 each with delivery. Today their up a little but they do run some 5 or 10% discount offers with free shipping from time to time.

[tmeagle1]

We purchased six new Good Year tires for our 1995 LY 30'. We paid $1325 that's removal of old, mount, balance and best old tire put on spare at local Good Year. A little pricey, old tires were 8 years old with little wear at all, we wanted future travels to be safe since we've always towed Airstream TT's in the past and Class A travel is new to us.

Tim

[Keyair]

Running straight circumferential grooved tires on the drive axle is normal. The sheer weight of our rigs, and the narrow section of the 8r or 225/70 means in wet you are not going to have issues with aquaplaning. However, a personal experience in a car with light snow and Z speed rated tires that had circumferential grooves has me concerned about traction on light snow or even wet grass. For that reason I am eyeing M&S rated tires. I might not be planning to go somewhere where we will need that, but we do plan to travel in winter and across mountains and the like and I’m trying to balance that safety margin agains any extra tire noise.
Take a look at Cooper Roadmaster tires. Made in China like all the budget tires, but to Cooper specs and QC.
Around about $200 a piece on EBay.
Look at RM 170, and RM 253.

[davejay]

Hey,
I run 245x65x19.5 tires on our 325. I don't like the skinny front tires. There's a lot of weight on the front end. A wider foot print gives you more stability. I run all the same tread on all 9 tires. Big trucks run snow tires in the rear for traction in weird places. Unless you plan on going off road, street treads are better. They are quieter, longer in mileage, wear better overall better suited for our application. You'll notice busses run street tires on all axles too. Traction is the big reason for heavy treading. My 245 s don't touch on the duals. That is a definite no no. Heat from the tread transfers to the sidewalks, thus blowout.
A lot of the reason why you'll see michlins and other high end tires on big rigs is because they can retread them multiple times. The carcass of the tire is heavy enough to use them 3 times. And truckers run these tires for 200 thousand miles, loaded most of the time. We don't work our tires like that. A suggestion for all , when you buy new tires, get them syped. Most shops don't know or have the capability to do spying anymore. It does not hurt the tire nor void the warranty. But I'll tell you what. It. Converts those street treads into all season tires, you will notice the change on wet roads or backing up in wet or snowy conditions. Make sure you have that inside tire aired up. That so often is the reason why you'll see a big rig on the side of the road with 2 flats on the same axle. You can buy a kit that equalizes the tire pressure between the duals. It even has a gage on it if you want see tire pressure right at the wheels. DJ

[Mike1997]

When I bought mine in 2015 it had Michelins. Front 2 were dated 2006, rear did not have dates which means they were made before 2000. I suspect the 4 rear were original from the factory. All had 40k miles and were cracked in multiple spots. Considering the coach had been stored inside its whole life...I do not think sun exposure caused the cracks but instead it was simply age.

At a high end tire shop the Manager said Michelins were known for crack failure if not driven. He recommends his motorhome customers go with Hankook tires which are common in the commercial truck market. They were about same price as the Michelins so had all replaced. 25k miles later, no problems and at rotation, there was little wear showing.

Side note...last summer while camping in Michigan, my neighbors came over who were in a Newmar Mountain Air 5th wheel that has 8 tires on it (two dual axles). After I noticed him staring at my tires, he commented, "only the best for the best"!! He was retired owner of multiple tire shops in Canada and very complimentary of the Airstream and full of praise for Hankook.

[Keyair]

Originally Posted by davejay

Hey,
I run 245x65x19.5 tires on our 325. I don't like the skinny front tires. There's a lot of weight on the front end. A wider foot print gives you more stability. I run all the same tread on all 9 tires. Big trucks run snow tires in the rear for traction in weird places. Unless you plan on going off road, street treads are better. They are quieter, longer in mileage, wear better overall better suited for our application. You'll notice busses run street tires on all axles too. Traction is the big reason for heavy treading. My 245 s don't touch on the duals. That is a definite no no. Heat from the tread transfers to the sidewalks, thus blowout.

I cannot find a 245/65 19.5 tires listed... did you mean 245/70?


Whilst I agree with you on the front axle loading, and cosmetics of the tire width, there are some other very important considerations.

Airstream and Cheverolet rate the P30 MH chassis under our 310/325/345 Motorhomes at 5,000lb.... so that is 2500lb per front wheel.
It is well documented that people have weighed their stock Motorhomes and been close to max or over max without too much gear onboard...

The Stock Alcoa width is 6", and there is a load rating stamped on my Alcoa wheels, of 2780lb.


I cannot seem to find the specs for the original Spec 8R 19.5 times, but I suspect it is about the same as the rim.

The closest and most common replacement for the 8R is the Metric 225/70 R19.5, and what it looses in overall diameter(33.1" vs 32.1"), it makes up for in load capacity. It is also wider than the stock 8r by some margin, and people who have swapped have stated it is more directionally stable too.

225/75 R19.5 "F" Rated tires can carry up to 3640lb single and 3415 dual @ 95psi. That is 860lb per tire over the capacity of the stock rim...

There is a "G" rated 225/70 option, that is weight rated at 3970lb per tire, but I see no logical reason to use those.

Then there is the subject of rim width.

Minimum manufacturer approved rim width for a 225/70 19.5 is 6" to 6.75".
Minimum manufacturer approved rim width for a 245/70 19.5 is 6.75 to 7.5".

Are you running wider rims than stock?

If not, I believe that there "maybe" safety/stability issues with running a 245 on a rim that is narrower than the tire manufacturer suggests... Not to mention the liability issue if you have a mishap, that is related to tire failure.

Each to his own, but I am, and will be running 225/70 R19.5 "F" rated, as it has more than enough safety margin and stability for me.

I'm not picking at you Dave, as you are not the only one I know who is running 245s... just putting it out there, so people know and understand, that the tire weight rating is not the limiting factor.

[Robfike]

The lack of a visible date code would just mean that the codes are on the other side of the tire.
Pre 2000 tires all had a 3 digit code

[davejay]

Hey,
I completely agree with you on what you said, regarding how wide a rim is verses tire size. You can go a little wider on tires. The mfger of wheels will give you some play in that area. One thing you can't do, is put a wide tire on a skinny wheel. That's where you get into trouble. You can't pull the sidewall in so far as to compromise the strength of the tire. People do it all the time. A 225 vs a 245 is about an inch difference. Half inch per side, that I can live with. Another thing is how wide is the footprint of the tire. You can have two exactly the same size tire, but the tread face can be considerably different. They met the size requirement, but skimped on the cost . Thus the skinny tread face. The front tires on an AS are pretty skinny for its weight and top heaviness. They just barely meet the weight requirements. That's why I went a little wider. Plus, it doesn't look so spindly, I think. It's just personal preference, but I get your point. DJ