# Cracked Tyres



## wavehead (Aug 6, 2013)

Recently I had both rear tyres of my Fiat/Swift Royal 610 crack around the inside (hidden) walls over a quarter of an inch wide and three quarters of the way arround the wheel. We were on a long trip and had covered 900 miles in 5 days, the tyres looked okay before setting off. The tyres had 3 years of use and were 4 years from manufacture with half the tread left. The van was below the manufacturers max weight by at least 100+ kgs per tyre. I have had 215/R15C load 107-109 on for the last 15 years but now wonder if it is possible to get higher than 109 load for the same size of tyre and should I get them. I always assumed the manufacturers load ratings would be conservative and leave loads of margin for safety eg 25%.
No I haven't lost faith in the particular manufacturer but would like to know about a higher load camper tyre for the same actual size if anyone can help.
Oh and yes we are lucky to be alive and I check the tyres regularly and it was Xmas day and big G was keeping an eye on us!


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## listerdiesel (Aug 3, 2012)

I doubt the cracking is from overloading, but might be from under inflation or perhaps overloading of one axle while remaining within the overall gross vehicle weight.

109 is just over 1000kg per tyre, that's 4 tonnes per 4-wheel set.

Peter


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## cater_racer (May 1, 2005)

It's hard to advise with the info given, don't be shy Wavehead what manufacturers tyres are they and what type? Agilis Michelin? Vanco Continental?

Been kept outside in the sun, in house, cold.......?


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## raynipper (Aug 4, 2008)

Yes, there is usually a contributary factor for tyres to crack. Mine was because they were over 9 years old.!!!!

Ray.


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## wavehead (Aug 6, 2013)

Just to confirm the vehicle was weighed and was not overweight on ANY wheel, as stated it was >100kg under per rear cracked wheel. Tyre pressure were okay and same as the last 17 years in that time I have had at least 5 sets of tyres as we do lots of mileage being full timers. What I am more interested in is the uprated tyre question.
Ta


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## Wizzo (Dec 3, 2007)

AFAIK 109 is the max load index for a 215 width tyre BUT if you swap to 225 wide then the load index will be 112. This will make your gearing taller by about 1.5% (and your speedo will be more accurate). They will fit on the same rim no problem.

I changed mine from 215 to 225 as part of uprating the MGW and the rear axle loading.

JohnW


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## Webby1 (Mar 11, 2012)

*Uprating tyres*

Because of an overloaded rear axle,like Wizzo, I also want to change

all 4 tyres to 225...................probably the Toyo H09.

As far as I understand there will be sufficient clearance etc on the

Ducato base but am concerned about any insurance loading as only

the 215s are listed in the original Fiat specifications.

They do know we have been re plated to 3850............anyone had any

experience of insurance companies and up rated tyres ?


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## listerdiesel (Aug 3, 2012)

We fitted 106 rated tyres instead of the original fitment 109 rated tyres and asked our insurers to comment.

Their written response was that as long as the tyres fit the rims correctly, and as long as the rims are the manufacturer's own and not aftermarket additions, they had no problem.

The tyre size was the same, just the load rating was slightly lower.

When we have gone up a size, same rule applies, if the tyre is correct for the rim, then there's no problem generally, and on most rims you can get two or three different sizes.

Ours are 8J X 16 and you can have 235 or 255 wide tyres fitted. I have 255's, our son has 235's, same rim.

Peter


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