Sumitomo HTR Z III review
 

I have had these for about a week now and I already cannot wait for the day I switch them out. I went for 245/40ZR-18 upfront and 265/35ZR-18 rears with the hope that they would provide decent amount of traction and better handling. Besides, the reviews on Tirerack were not too shabby and the price either.
Well, as far as traction is concerned, they seem to be spot on but handling is a totally different story. The tirewall seems so soft that the car now feels like a SUV with high center of gravity. At speeds of 70 mph, car sways from side to side if there's a slight input at the steering wheel and I can literally feel the weight of the car side to side. So my question is, is this because the tires are soft or because the side wall is taller? (265 at the rear and 245 front).
Will things improve if I switch to Hankooks or MPSS with the same size?
The tire installer told me that give them a few days to break in.
But if things don't improve, I am going to find myself an empty parking lot and smoke them.

Misread the above, forget it

Taller sidewall is not the cause - it's barely changed. Your sidewall is higher than stock by only 4mm. Front sidewall went from 94 to 98mm, rears from 89 to 93. That's negligible.

Sidewall flex is your problem. It could be just inflation pressure - have you checked that? If pressure is OK then it's a tire design issue, and a couple days of breakin won't fix it. Before smoking them off, I'd go back to my installer and see if he will help you swap them for something better.

I had similar symptoms getting new PSS on my car, perhaps not as drastic - the HTR Z3 are definitely not as stiff and precise as the PSS. I would give it a little while to see if it improves. I was honestly shocked at how 'boaty' my C63 felt after putting a new set on PSS to replace my last PSS, I thought something had to be wrong. As I turned in for any corner or bend, I felt the delayed 'wiggle' and drift feeling of the tires catching up to my input. However, a few months in, and I realize I haven't had that feeling for a long time. New treads, higher tread height, etc., will play into that.

That said, to my understanding the HTR Z3 aren't upper-tier like ultra/extreme summer tires, so they may never feel telepathic, but they should break in some over a month and you should start getting more comfortable with them.

Strange. I've always heard great things about HTRZ III's. One thing to keep in mind though -- since our cars are so heavy, we definitely need a tire with a tougher sidewall that most other cars if we want the car to feel "zippy".

I've got Hankook V12's with about 5/32 right now, and I too, feel that slushy delay when abruptly turning the wheel. My worn (5/32) PSS's were definitely better at quick steering inputs. I'm really curious to try a tire like AD08R or the new Bridgestone RE71R. Obviously an overkill for the street, but this car has to good of steering to put crappy tires on it.

Yea I saw these on tirerack for under $500, looking at those exact same sizes OP purchased.. The price caught my attention. What a waste of $500 tho if they end up being not quality tires...

You are right. The tires were a bit over inflated (49 psi front and 50 rear). I brought it down to 44 front and 46 rear and things seem to have improved but only marginally. The steering response is still mushy, a bit like how the non-sport C250's have.

Did you get the boaty feeling because you ordered one size up? With OEM spec tires (235/255), this definitely should not be an issue i guess.

I am surprised that you got the same feel with the Hankook's. I had hankook's on my previous C63 (235/255) and they felt great. my Audi has them too and they seem to be very decent for the price. Did you also order the Hankooks with the taller sidewall?

I thought they were a steal for under $500 so i got them. But I gotta admit that the grip is really good. Atleast, the ESP doesnt kick in now.

Get an alignment ASAP there's no tire out there that would cause all that u describing

Well, to be fully honest, Hankook V12's are pretty well known to be crummy summer tires. HTR ZIII's far surpass them in every category from my understanding. I know Hankook came out with their V12 Evo 2's -- not sure how they perform though.

I'm on an 8.5" front wheel so yes, I'm on 245/35/19 right now.

I'd try to put some heat into them to burn off the initial "layer" of the tire. It's commonly known that new tires can feel a bit uncharacteristic at first.

I just switched my rears only to these. I have 275/19s on a 9.5 rim and I am noticing some of the same conditions you are describing with the soft sidewall feel. Previous tires were Toyo T1Rs on the rears in the same 275 width. These sumitomos definitely feel softer. It's only been about a week since I put them on when taking off my winter set on 18" with continental DWS.


The new continental DWS 06 model has the exact same tread pattern but the sidewall is stiffer according to tirerack. I have yet to try the newer model DWS 06 tire but the difference between the DWS and the HTR Z III is noticeable from my part in similar ways as described by the OP.

Wait DWS or DW? The DWS is an all-season. I've had these and they made my M3 feel like a yacht.

That being said, I can promise DWS's feel nothing like HTRz's. (HTRz's should be light years stiffer, sharper, etc. -- all season vs. summer tire)

Yes, DWS, those are my winter tires.

Gotcha. So are you saying that there isn't much of a difference between the DWS and the HTRz's?

You mention your findings to be pretty similar to OP's -- soft, lazy. etc. so am a tad confused because normally moving from an all season to a max summer, or any summer tire, should feel much, much better.

Similar in respect to the HTR Zs I just switched to as the OP did, but to clarify, I did not experience what I'm experiencing now with the DWSs.

I just had the DWS06s mounted and they're awesome. I don't drive in the rain/snow/wet conditions (and I rarely go with all-seasons for my cars as they're fun cars for me not daily drivers), but mostly was looking for quiet tires with excellent dry traction. I wanted the MPSS but wanted to try something different. The treadlife, dry traction, and quiet ride sold me on the tires.

I'm very happy with them. Sidewall is softer than I'm used to, but that's fine for my purposes. I'm not a tracker or anything like that, just some spirited drives here and there mostly.


Anybody else have the DWS06s can comment? I personally think they're great for the price, only other tire I had that was better were the Nitto Innvos. Another great tire for the price, had those on the E55.

That is still to high. You should be running around 40 psi 'cold' at all corners. That is per the tire label on the car

True, but remember that the sidewall already feels too soft. Lowering the pressure will just make it worse. OPs problem isn't a pressure issue.

So it looks like the tires need some breaking in.... I think I might take a shot at these, I need some new tires soon!

Ya stay away from those tires. I want them to stay cheap so I can still buy them at a discount!

Honestly though I've been rolling on them for a while now. 19" and frankly I have been super happy with them. Great traction too boot. I run them up in the mountains with cars way faster than mine and I keep up very well.

Funny the comments on the conni's as we put them on a friends G35 and it was like driving a yaut as others stated.

Very curious if stock suspension or alignment have anything to do with it. I'm on coils and fairly low.

My set at 8000 miles tread wear and a few but outs. Tread wear is good esp on rear. No track use as these tires are not meant for that.


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