Tyre load ratings

Advice and help involving any mechanical issues.
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Greynomad
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Tyre load ratings

Post by Greynomad »

This is not strictly mechanical, but there doesn't seem to be an appropriate category.

Although mine is a caravan problem, it's probably worth motorhomers checking out this under-appreciated aspect of tyres on heavier vehicles.

Our 18ft van is a hybrid China/Oz production. The (single axle) chassis and bare box are made in China and shipped to Oz for internal fitout, wiring, etc.
They arrive in Oz by the container-load, fitted with three 15" rims & Chinese-made 235/75R15 tyres — two on the road and a spare.
As the van has a 2500kg ATM, the tyres fitted at manufacture are a 116 load index. This complies with Oz regulations.
The problem arises when the tyres wear and require replacement.
At some stage (probably just before we bought it) the previous owner REPLACED THE TWO 'ROAD' TYRES WITH 109 LOAD INDEX TYRES.
No-one (at least I can't find anyone) who sells 15" tyres in Australia stocks a load index higher than 109!
One SA retailer claims to sell them, but is "out of stock"… actually, he's "out of stock" on all tyre sizes!
Apparently all these vans are shipped with 15" rims, but people buying the dual-axle vans can legally replace the tyres with 109 load index, as the load is shared across four tyres.
A call to the Australian 'manufacturer' of the van was called for.
"Yes," was the response, "We can sell you three tyres and rims to suit."
:? "But I only want the tyres."
"Sorry, we only sell the tyres on rims."
"But the rims are not required, only the tyres are worn."
"Sorry, we only sell the tyres on rims."
"I don't think this conversation is going anywhere. Goodbye."

SOLUTION: I have just spent $2,000 buying 16" rims and 265/70R16 tyres — with a 120 load index — from a tyre retailing chain set up by a retired racing car driver (Not Mickey Thompson!) which — after a nasty legal battle — is now run by his son.
At least when these tyres wear down I can get replacements with the correct load rating.

This is what prompted this post:
Cheapsh!t Chinese tyre of insufficient load rating.
IMG_3722.jpeg
Fortunately I was climbing a steep hill at 50km/h when the tyre blew, and stopped safely.
BEFORE:
IMG_3762.jpeg
AFTER:
IMG_3763.jpeg

ps. Is anyone in need of three six-stud 15" rims & tyres for a trailer? :)
Two are LI-109, the original spare is LI-116. The replacement LI-109 tyre has only done 1500km.
They're legal for loads up to 2100kg ATM. ;)
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Regards & God bless,
Ray
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jon_d
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Re: Tyre load ratings

Post by jon_d »

if does get expensive.... I'm sort of considering going to 22 inch tubeless rims. They are about $300 each
And then the engineers need to be involved to certify the change.... plus the insurance company needs to be notified of the 'design' change.


It does appear that there are not to many 116 tyres about.

https://www.tyroola.com.au/v1-double-ki ... db428.html

https://www.tyresales.com.au/buy/tyre/d ... r15/204713?
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Re: Tyre load ratings

Post by supersparky »

Ray, I reckon that you have made a wise decision, a bit exxy, but wise none the less.
Jon, would you be planning on moving to alloy one piece rims or stay with steel one piece?
Cheers
David

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Re: Tyre load ratings

Post by jon_d »

I think steel.

The problem is the bolt length.
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T1 Terry
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Re: Tyre load ratings

Post by T1 Terry »

jon_d wrote: Thu Sep 07, 2023 1:53 pm if does get expensive.... I'm sort of considering going to 22 inch tubeless rims. They are about $300 each
And then the engineers need to be involved to certify the change.... plus the insurance company needs to be notified of the 'design' change.


It does appear that there are not to many 116 tyres about.

https://www.tyroola.com.au/v1-double-ki ... db428.html

https://www.tyresales.com.au/buy/tyre/d ... r15/204713?
Can you get 22.5 tubeless rims to fit the Daytona "spider" hubs or do you need to go to Budd type 10 bolt hubs?

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Re: Tyre load ratings

Post by jon_d »

8 bolt.

$250 each. from here; https://oceanicdirect.com.au/products/wheels-and-rims/

looks like this
New steer tyre.jpg
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Re: Tyre load ratings

Post by T1 Terry »

jon_d wrote: Sat Sep 09, 2023 5:38 pm 8 bolt.

$250 each. from here; https://oceanicdirect.com.au/products/wheels-and-rims/

looks like this
New steer tyre.jpg
Interesting, that site says they do super singles for demountable steel rims, I'm guessing they mean Dayton spider hubs and can make to order, so maybe 4 super singles to suit 22.5R tubeless tyres ..... gotta be easier to work with than duals on the rear and better traction ..... the super singles really uprate the load capacity over the front axle

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