gtstcactus

I've currently got all H rated tyres on my Windom....

I've got 2 V rated tyres sitting in the boot which I'm having fitted in the morning. From what I've read on the web it seems that it's not really recommended to mix different speed rated tyres, but it should be ok with V & H rated tyres as V is the rating directly after H. The various websites generally recommend putting the higher rated tyres on the front axle to prevent over steer.

The V rated tyres have much more tread on them as they are almost new 90-95% tread on them where as the 2 H rated tyres I'm keeping have about 70-75% tread on them.

I've always worked on the basis that you put the tyres with the most tread on them on the driving wheels which in the case of a Windom/ES300 is the front, which doesn't fit with the recommendations I've read.

Does anyone have any actual experience with this? Is it likely to be problematic putting the V rated tyres on the front & the H rated on the rear?

I want to know so I can decide if I should rotate the tyres myself before I go to the tyre shop and have the new ones fitted. They charge for rotating the tyres and I'd sooner save myself a few dollars and rotate them myself by moving the ones I'm keeping to the rear and moving the ones I'm getting rid of to the front.

Jeremy-KY

Put your new tires on rear, and your old tires up front.

From my personal experience, with my Windom, the newer tires on front will produce over-steer, especially in the rain, I've spun out a lot of times to attest to this, it doesn't matter if they are H rated or V rated tires. The H and V Ratings on the tires are "speed rating", with real world driving, your Windom will never reach the speed of those ratings. (130 mph, 210 km/h for H rating; 149 mph, 240 km/h for V rating)

Always put new tires in the rear.

My best recommendation however is to get a complete matching set and have the wheels balanced.

tomf

If you can tell the difference in the handling and the ride of your ES300 depending on where the different speed rated tires are located you are a better person than me. IMO I wouldn't give it a second thought.

Conventional wisdom is to put the tires with the most wear on the front. Why? Supposedly the risk of the rear tires losing traction during hard braking or when in a turn under adverse conditions is higher if the more worn tires are on the rear. This loss of traction could be the cause of an accident and injury and/or loss of life. Of course if you have vehicle stability control that mitigates the chances of losing traction in a turn.

Personally and contrary to conventional wisdom, I put the the tires with the most wear on the rear. I think the benefit of greater traction in the front outweighs the risk I described above. I think that risk is overstated. And based on my personal experiences I'm happy with my choice. Last time I had new tires put on the front the tire store made me sign a waiver. LOL.

Jeremy-KY

This is so true, I've once tried different tires front and rear, I once had Toyo Proxies T1R's in the front, and Nexen N3000's in the rear (both were Z rated tires (Speeds greater than 149mph, 240 km/h)), The grip difference between the two tires was huge, In the dry, the car had literally no under-steer at all, however in the rain, the lack of grip on the rear of my Windom, made the vehicle rotate very easily even with Traction control on.

I can only imagine that if my vehicle had VSC, it wouldn't work properly either. I don't think VSC can compensate for differences in Tire Grip from front and rear. I would believe having tires matching front and rear would be optimal for VSC to work properly

And having different tires with a huge grip difference in the front vs rear, it was very easy to spin the vehicle taking any corner at any speed in the rain. even at low speed.

The Windom's weight distribution is pretty much front heavy, so having worn tires on the rear of this vehicle, will amplify its tendancy to spin in adverse conditions.


@ OP, If you are prepared for this, feel free to experiment, like they say experience is a good teacher.

Speed Ratings are one thing, but don't forget that there is more to a tire than Speed Ratings, you also have different compounds to deal with, different tread patterns, sidewall stiffness ... the list can go on.

I've learned from my experience, and that was from almost writing off my vehicle in a ditch because of different grip levels of the tire.

I'm not much of a risk taker, so I would personally rather be safe, than out of a vehicle the next day.

So if you can, just to be on the safe side of things, I would suggest waiting until you can afford two more of the new tires you have now.


There's no harm in mixing different speed ratings however, just as long as you put the new tires on the rear of the vehicle.


Stay safe out there, as you never know what kind of road conditions you might one day end up having to drive through.

Tire Rack has a wealth of information that might be handy for you to read, you can check it out here http://www.tirerack.com/tires/tirete....jsp?techid=35

gtstcactus

Some interesting advice there, you learn something everyday!

In all honesty I think the tyres I currently have on the rear are more likely to lose traction under any circumstances than anything I could put on there with decent tread... The rear tyres which I'm replacing have gone past the "time to replace indicators" - they've got tread left across about 3/4s of the tyre with less than 1mm of tread depth all round, however they are H rated...

The tyres I've got on the front at the moment at about 75% tread depth are quite some way off being replaced. I'm not really keen on replacing them at the moment, but will try and at least get V rated tyres as replacements, perhaps next time I'll have the $ to do a set of 4!

I'll just get the tyre shop to put the V's on the rear and leave the H's on the front for now and save myself the $20 it'll cost to rotate them and put it towards some transmission fluid.

Jeremy-KY

While were on the topic of tire wear, were your rear tires previously on the front? I find it strange for your rear tires to be worn more than the front, unless of course the worn tires were originally on the front, and then you had them previously rotated to the rear.


Either way, I suppose It wouldn't hurt to look into checking for any alignment issues later down in the future, because any uneven and accelerated tire wear, can come from out of spec wheel alignment.

tomf

The whole point of VSC is to detect when the vehicle is sliding. The VSC system, upon detecting a sliding motion, applies independent braking to prevent the slide. The VSC system doesn't know or care if the cause is worn tires on the rear or ice on the road or the car is hydroplaning. All it knows is the vehicle is sliding. Regardless of the cause the VSC mitigates the slide. +

I agree in theory, identical tires are the best. Of course we live in the real world and most people do not have the luxury of always doing the optimal thing. There are trade-offs in everything.

gtstcactus

When I got the car a couple of months back all 4 tyres where getting close to being below the legal tread depth limit of 1.5mm. On or around Xmas Eve, I replaced the worst 2 tyres with a good pair (75% tread approx) I got from a wreckers (H rated), and put them on the front - my logic being the driving wheels should have the tyres providing the most traction. That left 2 tyres on the rear needing replacement within a month.. I scored a pair a couple of days ago from another wreckers (V rated) which are now on the rear...

So all in all I think it's got to be much safer now than when I got it!

I'll try and get a wheel alignment done next week.

2GSKaizen

iTrader: (1)

Speed rating won't matter, as long as the tires sizes are the same outer diameter +/- about 5%

gtstcactus

Yeah tyres all the same size etc..

I'm glad I didn't pay for a wheel alignment when I got the tyres put on! I had a gut feeling when I put it in for a WOF that the things most likely to fail it that I couldn't easily detect myself was excessive play in the suspension or steering. It's not because the car is doing anything strange, or feels wrong. Previous experience with my Nissan Skyline told me those areas would be the only thing I'd probably not detect a problem with... Excessive play can be 1.5mm of movement when it's spec'd for 1mm, lol...So some would say it's splitting hairs but whatever - the rules are the rules and I'd prefer the vehicle is "safe", tho I think it is anyway.

So I just need to get the part id'd as the culprit changed in the steering rack and then I'll get the alignment done...

Jeremy-KY

Sounds good man =) Happy Driving!!