Lexus IS300h rear wheel losing grip

[Sazabi2001]

Hi Everyone.

I got my IS300h about half years now, I love almost everything about this car.

But there is still a small problem, the rear wheel always tends to lose grip / traction. It gets worst if it is in a turn slightly uphill or downhill with a little bit of wet, even in eco-mode I have to press the accelerator gently.

Some said it's about the tyres, so I change all 4 wheels to Yokohama AD-08R, that should be the one of the best grip tyre. It's better now but still slides.

Some said it was the common problem for RWD, but I had a vintage 911 still better than the IS300h in terms of grip.

225 tyre dose not seem  small size for 220bhp car, and I don't think it should need a bigger tyre.

====

Anyway, I was told that Toyota build all their car for drifting, I should live with it.

[alpine]

2 minutes ago, Sazabi2001 said:

Hi Everyone.

I got my IS300h about half years now, I love almost everything about this car.

But there is still a small problem, the rear wheel always tends to lose grip / traction. It gets worst if it is in a turn slightly uphill or downhill with a little bit of wet, even in eco-mode I have to press the accelerator gently.

Some said it's about the tyres, so I change all 4 wheels to Yokohama AD-08R, that should be the one of the best grip tyre. It's better now but still slides.

Some said it was the common problem for RWD, but I had a vintage 911 still better than the IS300h in terms of grip.

225 tyre dose not seem  small size for 220bhp car, and I don't think it should need a bigger tyre.

====

Anyway, I was told that Toyota build all their car for drifting, I should live with it.

911s are rear engined, so of course have better traction in icy conditions.

[Sazabi2001]

2 minutes ago, alpine said:

911s are rear engined, so of course have better traction in icy conditions.

If modern 911, that's true.

For old 911, especially those torsion-bar one, traction is only available in straight line.

[rayaans]

1 hour ago, Sazabi2001 said:

Hi Everyone.

I got my IS300h about half years now, I love almost everything about this car.

But there is still a small problem, the rear wheel always tends to lose grip / traction. It gets worst if it is in a turn slightly uphill or downhill with a little bit of wet, even in eco-mode I have to press the accelerator gently.

Some said it's about the tyres, so I change all 4 wheels to Yokohama AD-08R, that should be the one of the best grip tyre. It's better now but still slides.

Some said it was the common problem for RWD, but I had a vintage 911 still better than the IS300h in terms of grip.

225 tyre dose not seem  small size for 220bhp car, and I don't think it should need a bigger tyre.

====

Anyway, I was told that Toyota build all their car for drifting, I should live with it.

Its not BHP you need to worry about. Its the torque. 

The IS300h has instant torque so in slippery conditions, you can cause it to slip very slightly until the traction control kicks in

Also, I would say its probably the size of the tyre. The higher trim levels have 255's on the rear which are better for outright grip. 

Its also worth remembering its been extremely cold, therefore the tyre compound is going to be harder and provide less grip anyway. Below 7 degrees they tend to go harder and you might consider getting winter tyres which would help.

[GSLV6]

Tyre grip isn't always about tyre width!  That's a bit of an urban myth, because grip is = force =pressure x area, and depending on a car's weight, driving wheels and axle loading, sometimes width isn't everything as grip is derived from tread pattern deformation (ie the heat generated from the tread (not the sidewall) deforming under torque, vertical loading or cornering forces.

The point at which width becomes relevant to move up to a wider profile is when 1) cornering forces over-stress and overheat the tyre tread, or 2) when torque and acceleration forces overheat and over-stress the tyre tread.  In both cases, a loss of grip will occur.  However, there comes a point, especially in the wet, where loss of grip can go hand in hand with wider tyres which don't have sufficient pressure generated over the tread area to overcome some of the loss of friction of wet conditions.

I have driven the IS300 in the wet and wouldn't say it generated as much torque low down as say our diesel vRS which outputs maximum torque from not that far above tickover!  We can drive that in the wet without losing traction, albeit that is fwd.

There are other things that it could be.  When you lose grip in the wet, you say it is worse on a corner, especially of up-hill or down hill?  In each case, you are either loading the suspension and asking for traction, or slightly unloading the rear on drive (downhill where some force is transmitted to the front axle) but loading it in lateral motion, whilst applying torque from gentle throttle movements.  It is possible that your wheel geometry could be slightly out, which can cause break of traction sooner than expected, especially in the wet, or simply that with the combined mass of the rear axle loading, cornering and acceleration force, tyres are being overloaded.  I would just have a look at the suspension before drawing too many conclusions.

If the suspension is fine in relation to geometry, then suspension stiffness, combined with the heavier axle load of a hybrid might, combined with electric torque, take more getting used to and care in the wet.

[olliesgrandad]

Very surprised you are having grip issues with the IS. It is in my opinion one of the best balanced rear wheel drive cars I have driven.

The worst I have ever owned was a 2.8 BMW Z3. Pull away too sharply on a dry road and it was a big sideways experience!

[dargoion]

You can check if the tiers are not over inflated and also change the rear ones with the ones from the front being a rear traction they tend to get used faster. I have a bit of traction loss on mine but traction control gets it back in no time

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[Sazabi2001]

6 hours ago, GSLV6 said:

Tyre grip isn't always about tyre width!  That's a bit of an urban myth, because grip is = force =pressure x area, and depending on a car's weight, driving wheels and axle loading, sometimes width isn't everything as grip is derived from tread pattern deformation (ie the heat generated from the tread (not the sidewall) deforming under torque, vertical loading or cornering forces.

The point at which width becomes relevant to move up to a wider profile is when 1) cornering forces over-stress and overheat the tyre tread, or 2) when torque and acceleration forces overheat and over-stress the tyre tread.  In both cases, a loss of grip will occur.  However, there comes a point, especially in the wet, where loss of grip can go hand in hand with wider tyres which don't have sufficient pressure generated over the tread area to overcome some of the loss of friction of wet conditions.

I have driven the IS300 in the wet and wouldn't say it generated as much torque low down as say our diesel vRS which outputs maximum torque from not that far above tickover!  We can drive that in the wet without losing traction, albeit that is fwd.

There are other things that it could be.  When you lose grip in the wet, you say it is worse on a corner, especially of up-hill or down hill?  In each case, you are either loading the suspension and asking for traction, or slightly unloading the rear on drive (downhill where some force is transmitted to the front axle) but loading it in lateral motion, whilst applying torque from gentle throttle movements.  It is possible that your wheel geometry could be slightly out, which can cause break of traction sooner than expected, especially in the wet, or simply that with the combined mass of the rear axle loading, cornering and acceleration force, tyres are being overloaded.  I would just have a look at the suspension before drawing too many conclusions.

If the suspension is fine in relation to geometry, then suspension stiffness, combined with the heavier axle load of a hybrid might, combined with electric torque, take more getting used to and care in the wet.

That sounds fair.

Well, I certainly don't hope there is a problem in rear suspension, since it is a pretty new car.

It is not bad traction, just not as good as I wished.

It is the most expensive car I ever own, maybe I just need to get used of it.

[Sazabi2001]

4 hours ago, olliesgrandad said:

Very surprised you are having grip issues with the IS. It is in my opinion one of the best balanced rear wheel drive cars I have driven.

The worst I have ever owned was a 2.8 BMW Z3. Pull away too sharply on a dry road and it was a big sideways experience!

Well, other than an old 911 that too slow to lose traction, I've never driven any other car that has 'sportiness' in it. All cars I used to have was just some diesel car with small engine.

[Sazabi2001]

1 hour ago, dargoion said:

You can check if the tiers are not over inflated and also change the rear ones with the ones from the front being a rear traction they tend to get used faster. I have a bit of traction loss on mine but traction control gets it back in no time

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I'll check the tyre pressure.

Maybe I just not getting use to the traction control thing yet.

[dargoion]

Yea and if you change tyers from front to back at least you are sure the tyers are not to blame

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[GSLV6]

If your car is equipped with the TPMS system, you may not be able to swap fronts with rears because the valve sensors will be coded to each specific corner of the car (they were with my GS).  If this is your first RWD car, it's just likely that you need to get use to it.  Change of gradient (up or down) and a wet, tight corner usually means low grip section of road, along with adverse cambers.  If it doesn't do it on flat corners or in the dry, I'd just get used to it but as mentioned, check tyre pressures before anything else.  Under inflated tyres can cause excessive roll in corners and this can also lose you control as well as over inflated tyres which will reduce (not increase) grip levels, especially when cold and damp.

[marrat]

17 hours ago, olliesgrandad said:

Very surprised you are having grip issues with the IS. It is in my opinion one of the best balanced rear wheel drive cars I have driven.

The worst I have ever owned was a 2.8 BMW Z3. Pull away too sharply on a dry road and it was a big sideways experience!

I thought such cars were build to be driven sideways most of the time 

[alpine]

On 25/01/2017 at 11:39 AM, Sazabi2001 said:

If modern 911, that's true.

For old 911, especially those torsion-bar one, traction is only available in straight line.

You wouldn't say that if you'd seen Bjorn Waldegaard wiping the floor with the Escorts at Lydden Hill in the 1970s! And of course, with limited slip diffs, traction is not just available in a straight line.

[dutchie01]

Hi Yong,

This sounds wrong.

i strongly suggest to visit the dealer and have the traction control system inspected.

I just cannot drift spin or whatever with my IS as the traction control steps in immediately if wheels loose traction. The engine immediately looses power revs drop regardless what you do with the throttle and the brakes are active on the wheel(s) neccesary. All this is instant and without hesitation or possibillitiy to influence. BMW has a more forgiving TCS that allows a certain drift angle before the system pulls you right but not the IS. I am told this is to prevent the rear wheels spinning and overrevving the electric motor.

Anyhow, your story seems there could be something seriously wrong with the TCS system is it functional is it working?? 

 

take care

 

Dutchie 

[200h]

traction control on toyota / lexus hybrid is normally quiet servere as in it cuts in quiet quickly

get yourself a 4 wheel geometery check and have it adjusted if necessary ,either lexus

can do it but it does become quiet pricey at about £100 for a 1 time check & adjust,

most kwik fit centres have the hunter hawkeye tracking system these systems are absolutely

spot on you can pay £120 to have your tracking adjusted up to 8 times in a 2 year period

so better value for money.

 

 

 

[DanD]

Actually this is a very good point: could you maybe have switched the traction control off by mistake?

[dargoion]

Even if you switch it off it will come on again when you start the engine for what i know you can't switch it off permanently

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[olliesgrandad]

On ‎27‎/‎01‎/‎2017 at 11:30 AM, 200h said:

traction control on toyota / lexus hybrid is normally quiet servere as in it cuts in quiet quickly

get yourself a 4 wheel geometery check and have it adjusted if necessary ,either lexus

can do it but it does become quiet pricey at about £100 for a 1 time check & adjust,

most kwik fit centres have the hunter hawkeye tracking system these systems are absolutely

spot on you can pay £120 to have your tracking adjusted up to 8 times in a 2 year period

so better value for money.

 

 

 

I never use Kwik Fi having had a bad experience many years ago.. My local tyre company I use in Gloucester (Chris Mullins Tyres) has the full works and I got him to do a full 4 wheel alignment and geometry check  when I bought my car. It was all spot on and done for free. He knows I will be back for tyres .(He is ex Protyre and his prices usually are a couple of pounds per cover cheaper). He tells me that Lexus usually run with a slight negative camber.

Regarding the traction control it is far less obtrusive when it cuts in than any other car I have owned.

[200h]

when on ice or snow the traction control cuts in and cuts power so you can end up becomming stuck

this is why there is a snow button to help you get out of trouble,it cuts in quickly to protect the motors

on the early CT's there isn't a snow button and you can become stranded.

[Sazabi2001]

On 1/26/2017 at 6:34 PM, dutchie01 said:

Hi Yong,

This sounds wrong.

i strongly suggest to visit the dealer and have the traction control system inspected.

I just cannot drift spin or whatever with my IS as the traction control steps in immediately if wheels loose traction. The engine immediately looses power revs drop regardless what you do with the throttle and the brakes are active on the wheel(s) neccesary. All this is instant and without hesitation or possibillitiy to influence. BMW has a more forgiving TCS that allows a certain drift angle before the system pulls you right but not the IS. I am told this is to prevent the rear wheels spinning and overrevving the electric motor.

Anyhow, your story seems there could be something seriously wrong with the TCS system is it functional is it working?? 

 

take care

 

Dutchie 

Hi Dutchie:

 

It is not really that spinning or drifting, and the traction control did cut in and reduce the power.

But..

I used to drive a diesel Passat, same driving style, and the traction control didn't come in as often as the IS.

Also, sometime you can feel a little bit wheel spinning before the power reduced.

But sure, I'll have my IS suspension check in next service.

Thanks.

[Sazabi2001]

On 1/26/2017 at 2:15 PM, alpine said:

You wouldn't say that if you'd seen Bjorn Waldegaard wiping the floor with the Escorts at Lydden Hill in the 1970s! And of course, with limited slip diffs, traction is not just available in a straight line.

Well, I don't have the LSD on it.. It's too expensive, and I don't do track day things other than go-kart.

[Sazabi2001]

16 hours ago, olliesgrandad said:

I never use Kwik Fi having had a bad experience many years ago.. My local tyre company I use in Gloucester (Chris Mullins Tyres) has the full works and I got him to do a full 4 wheel alignment and geometry check  when I bought my car. It was all spot on and done for free. He knows I will be back for tyres .(He is ex Protyre and his prices usually are a couple of pounds per cover cheaper). He tells me that Lexus usually run with a slight negative camber.

Regarding the traction control it is far less obtrusive when it cuts in than any other car I have owned.

I do notice that Kwik-Fit centres usually have very good wheel alignment tools, and I plan to do this for may old car.

But I also know their service is crap so I'll watch them do it.. I guess.

[200h]

7 minutes ago, Sazabi2001 said:

Hi Dutchie:

 

It is not really that spinning or drifting, and the traction control did cut in and reduce the power.

But..

I used to drive a diesel Passat, same driving style, and the traction control didn't come in as often as the IS.

Also, sometime you can feel a little bit wheel spinning before the power reduced.

But sure, I'll have my IS suspension check in next service.

Thanks.

yes that is a diesel Passat you now have a hybrid lexus , the lexus has electric motors that need protecting

this is why it cuts in quickly ,I personally don't think there is anything wrong with your car its just different to

the Passat.

[Sazabi2001]

16 hours ago, 200h said:

when on ice or snow the traction control cuts in and cuts power so you can end up becomming stuck

this is why there is a snow button to help you get out of trouble,it cuts in quickly to protect the motors

on the early CT's there isn't a snow button and you can become stranded.

So the snow button is not really for icy days, it is only for getting out from the ice?