[mountainman]

I wanted to share my experiences with replacement tyres with this forum.
We tend to spend half hour driving time on secondary roads where in Queensland are coarse chip spray bitumen. The Hankook tyres work very well on this car with the exception of coarse chip when the roar will drown out the radio. We put up with the noise for about 3 years but as with all tyres the noise gets worse as they wear down.  The tyres were worn down to about 50% after about 31,000 km.

I spent way too many hours researching tyres which performed at least as well as the Hankook tyres but were quieter. This is made more difficult as there is not a great overlap with tyres available here in Australia and those in the US and Europe.

The 205/55 R16 tyre which would fit the car and scored best on the quiet and conform stakes was the Toyo Teo Plus. In tyres with profiles 55 and smaller they add an extra sound deadening rubber belt inside the tyre.

I took the plunge and bought a new set from Tyre Zone which had a special price of $645 and a rebate from Toyo so the net cost was going to be $615.

After driving for a few kilometres it was obvious that these tyres did indeed make a significant difference in noise and comfort.

Previously I had measured the noise from the original tyres with a sound level meter. I repeated the measurements with the new tyres to see if it was deluding myself. The numbers are set out below. The dBA scale give more weight to sounds in the range of the human voice and less to low frequencies and is usually used to measure noise.

The figures indicate that the Hankook tyres will sound 4 times as noisy on coarse chip as the Toyo tyres. The other interesting thing to note is that there is very little difference on smooth hot lay bitumen.

Conclusion:
If you do a lot of driving on secondary coarse chip roads the Toyos make a big difference to noise.
If you are going to be driving on high quality roads all the time there will be little or no benefit noise was in changing to the Toyos.
The Toyos do have soft sidewalls so I would be careful of gutters.

Car: 2009 Hyundai CRDI SLX with 205/55 R16 Tyres
Original Tyres: Hankook Optimo K415  205/55 R16 91H
New Tyres : Toyo Teo Plus 205/55 R16 91V
Inflation Pressure: 36 PSI  (Cold)
Sound Measurements made using slow response and A weighting at the passenger's  ear.

Road Surface   Speed     Hankook K415   Toyo Teo
                        kph          dBA                    dBA
Coarse             60           75                      69
Coarse             80           77                      72.5

Smooth             80          65                      65
Smooth            100         NA                      69

[Doggie 1]

Great info.
Thanks for that & welcome to the forum, mountainman. 

[Phil №❶]

Welcome mountainman,

Excellent 1st post 

[Surferdude]

Great informayion mountainman and it confirms someone else's comments on here some time back IIRC.
I have one question for you though.

Could you please expalin what you mean by "soft sidewalls"?

[mountainman]

After reading about how great these tyres were I knew there must be a trade off somewhere.
I asked the installer what that was and he said the tyres had 'soft sidewalls' and there would not be a sharp steering response. Then he said the Hankook was were similar and I probably would not notice the difference.
At 32psi the car seems to float on the tyres and the steering is strange. At 36psi they feel right. The load rating of the tyres is the same.
 
I also note the tyres look a bit 'flatter' on the front than the hankooks. 

I am just going to be a bit more cautious on rocky dirt roads.

[Doggie 1]

Mine look a bit flatter on the bottom, rather than the front.  I hope they're ok.

[Surferdude]

After reading about how great these tyres were I knew there must be a trade off somewhere.
I asked the installer what that was and he said the tyres had 'soft sidewalls' and there would not be a sharp steering response. Then he said the Hankook was were similar and I probably would not notice the difference.
At 32psi the car seems to float on the tyres and the steering is strange. At 36psi they feel right. The load rating of the tyres is the same.
 
I also note the tyres look a bit 'flatter' on the front than the hankooks. 

I am just going to be a bit more cautious on rocky dirt roads.

Thanks mm for the response.
Pretty much all passenger tyres have the same number of sidewall plies (2 actual) and the plies themselves are of the same thickness (denier) so unless you have a very low profile tyre where they run the ply turnup higher up the sidwalls, they should all be the same.
Occasionally you get a tyre with a slightly narrower tread pattern but because it is on the same width carcass, the sidewall can look a bit more exposed.
Anyway, at 36psi I doubt you'll have any more issues than with any other similar sized tyre.
Enjoy the Toyos. 
They're good tyres.

[Dazzler]

Welcome mountainman,

Excellent 1st post 

  That is a BIG difference on course bitumen  (I wonder how that would compare with the continentals that Alan recommends?

[mountainman]

Thanks Suferdude in regards to ply counts.

I checked the sidewall of the tyres:

Tread:     2 steel, 1 Nylon and 1 polyester
Sidewall: 1 polyester

I would assume that Toyo know what they are doing using just one ply on the sidewall. I have not seen any reviews complaining of  damage on gravel roads. Keeping my fingers crossed.

One of the reasons for choosing the I30 was that it had decent ground clearance for a hatch. Makes driving on gravel roads less nerve-raking. I have been tempted by some of the super efficient diesels like the vw bluemotion but they are just too low to be practical for anything but city driving.
 

[Surferdude]

Thanks Suferdude in regards to ply counts.

I checked the sidewall of the tyres:

Tread:     2 steel, 1 Nylon and 1 polyester
Sidewall: 1 polyester

I would assume that Toyo know what they are doing using just one ply on the sidewall. I have not seen any reviews complaining of  damage on gravel roads. Keeping my fingers crossed.

Yeah, sorry. My bad.
1 ply sidewalls all round these days. Serious typo and poor proof reading skills.
I have Goodyears and Dunlops on my two cars.
Both 1 ply polyester sidewalls.
It's not a Toyo only thing.
The thickness of the cords is what gives the tyre its strength.
Even truck tyres will have only 1 ply (but 16 "ply rating")  The difference is the truck tyre plies are steel not polyester.

The figures indicate that the Hankook tyres will sound 4 times as noisy on coarse chip as the Toyo tyres

Without detracting from your excellent evaluation of which I am very interested because my tyres are just as noisy as everyone else's I would like to correct your submission that the Toyo tyres will sound 4 times less noisy than the originals.

It's a technical matter only and not a criticism.

A SPL measured in dbA (weighted for our ear response) will require a difference (dbs are ratios) of something like 10db for a subjective doubling or halving of sound level. The best from your measurements is about 6db so I'm thinking that would sound something like a reduction of less than half - not a quarter which would measure more like 20 db less.

Just as a matter of interest, how would you describe it?  I realise this requires a bit of imagination because you cannot compare back-to-back but would you have said 4 times less before you took the measurements?
 

[mountainman]

Hi Pip,
          yes the theory is that it requires 10db to sound halve the perceived sound level. To my ears it sounds less than half the level. Even on smooth bitumen they sounded quieter to my ears even thought the measurements show no difference. Without performing a frequency analysis of the noise( which is not hard to do these days with laptop and a sound level meter) it seems the irritating higher frequency sounds are gone. You can still hear the difference between smooth and coarse bitumen. Going over a section of concrete highway just north of Caloundra north of Brisbane there was absolutely no difference to smooth bitumen. Normally this creates a whine inside the cabin.

          One should also be aware there may well be differences between different sizes of tyres. I have read that lower profile tyres tend to be noisier.

           I have not tried running the tyres at the cars recommended pressure of 32psi for more than a few km but this could reduce the noise further. When I did run them at 32psi the the car seemed to float along. This just did not feel right and steering was strange.

           Choice has done tests on these tyres with others and published noise figures. The problem is they do not state the inflation pressures nor the road surface they tested on.

          I hated to discard 4 good tyres which had a good 20k left in them but to my ears it was worth it.

Hope this helps

[Dazzler]

Going over a section of concrete highway just north of Caloundra north of Brisbane there was absolutely no difference to smooth bitumen. Normally this creates a whine inside the cabin.

I know that piece of road from one of our visits up there driving a rental i30 (It was so bad I got out to check if I had a puncture) 

I hated to discard 4 good tyres which had a good 20k left in them but to my ears it was worth it.

Try and sell them for maybe $100 total for the 4 .. might be ok for some to use on a trailer or if they are selling their car