New winter tyres but no rear stability

dcmraad

Hi guys. need a little help.

I have my winter tyres on for the last 3 days FWD, the difference is very noticable.

I now have the problem of the arse of my car trying to overtake me on right angle bends or roundabouts at very slow speeds, under 15 mph.

I dropped the pressure in the rear tyres to 15 from 32 and it was still the same.

Anyone any ideas

JJJJNR

Have you winters on the front driven wheels only, you need them on all four.

johnos1984

JJJJNR wrote: »

Have you winters on the front driven wheels only, you need them on all four.

I've only got them on the front but with a gently style of driving they have been great and I have really tested them.

OP if they are on the front and you are turning sharply the rear will step out.

Check if they are directional tyres and if they are on the correct way round. I had to swap mine

MagicMarker

Yeah, I would have the thought the answer was quite obvious.

Either buy 2 more tyres or slow down even more.

Irish Steve

dcmraad wrote: »

Hi guys. need a little help.

I have my winter tyres on for the last 3 days FWD, the difference is very noticable.

I now have the problem of the arse of my car trying to overtake me on right angle bends or roundabouts at very slow speeds, under 15 mph.

I dropped the pressure in the rear tyres to 15 from 32 and it was still the same.

Anyone any ideas

What sort of load is in the vehicle? We used to have a Talbot Sunbeam ( 20 years ago) and it was a nightmare on the Swords Ashbourne road in the mornings until we found the answer, which was to put a few concrete blocks in the boot, and that helped big time to nail it down. Other alternatives would be bags of rock salt, (useful in ice) or gravel or sand, whatever, at least 2 25 Kg bags.

Steve

johnos1984

Irish Steve wrote: »

What sort of load is in the vehicle? We used to have a Talbot Sunbeam ( 20 years ago) and it was a nightmare on the Swords Ashbourne road in the mornings until we found the answer, which was to put a few concrete blocks in the boot, and that helped big time to nail it down. Other alternatives would be bags of rock salt, (useful in ice) or gravel or sand, whatever, at least 2 25 Kg bags.

Steve

Thats a great idea in RWD cars for anyone with issues.

I've been carrying the two tyres without winter tyres in the boot and this had probably helped me a bit also

Biglad

dcmraad wrote: »

Hi guys. need a little help.

I have my winter tyres on for the last 3 days FWD, the difference is very noticable.

I now have the problem of the arse of my car trying to overtake me on right angle bends or roundabouts at very slow speeds, under 15 mph.

I dropped the pressure in the rear tyres to 15 from 32 and it was still the same.

Anyone any ideas

Protyre is keen to dispel the idea that drivers should reduce tyre pressure for driving in snow. This can be both illegal and dangerous.

For best traction in these conditions, all tyre pressures should be maintained at the manufacturer’s recommended pressures, details of which can be found in the vehicle’s handbook.

2 or 4, what have you got...

Matt Simis

Biglad wrote: »

Protyre is keen to dispel the idea that drivers should reduce tyre pressure for driving in snow. This can be both illegal and dangerous.

For best traction in these conditions, all tyre pressures should be maintained at the manufacturer’s recommended pressures, details of which can be found in the vehicle’s handbook.

Exactly and when using Winters (Im also not clear if the OP has Winters on the rear) you are explicitly told to run at normal pressure always, do no reduce it. Reason being they have the thread to "bite" into Snow and Slush, the higher the pressure (within reason) the better they bite. Deflating them reduces their effectiveness.

but43r

Only other thing that I can think of would be rear wheel alignment? This could be caused by bent suspension parts in the rear or the alignment could just be out. Check if both wheels appear to be parallel to each other.

Could your handbrake be jamming by any chance???

Edit: Just read the post again and its hard to understand what you mean. Do you mean you have four winter tyres on you FWD car or you have winter tyres just on the front wheels of your FWD.
If it is just two tyres on front wheels than back kicking out will be pretty normal even when driving slowly.

snowman707

Biglad wrote: »

Protyre is keen to dispel the idea that drivers should reduce tyre pressure for driving in snow. This can be both illegal and dangerous.

For best traction in these conditions, all tyre pressures should be maintained at the manufacturer’s recommended pressures, details of which can be found in the vehicle’s handbook. [/B..

for the last couple of weeks I have repeated advise here to reduce tyre pressure in snow,

yet when this was suggested on a U.K. site on which I contribute, the OP got a yellow card for offering dangerous advise

johnos1984

snowman707 wrote: »

for the last couple of weeks I have repeated advise here to reduce tyre pressure in snow,

yet when this was suggested on a U.K. site on which I contribute, the OP got a yellow card for offering dangerous advise

It is dangerous.

HOWEVER

AFAIK if you are badly stuck reduce the pressure to get the car going.

Don't drive far though. Drive safely and appropriately before going to the nearest garage and inflating your tyres to the correct pressure.

If I'm incorrect I apologies however that is my understanding.

Biglad

snowman707 wrote: »

for the last couple of weeks I have repeated advise here to reduce tyre pressure in snow,

yet when this was suggested on a U.K. site on which I contribute, the OP got a yellow card for offering dangerous advise

That advice seems to be wrong and dangerous so...

leeroybrown

If you only have two winter tyres on the front end of an FWD car you're asking for trouble unless you're incredibly careful. They'll lull you into a false sense of security with the improved grip for acceleration, braking and turn in, then the rear end grip will eventually let go leaving you in a nasty spin.

Biglad

johnos1984 wrote: »

It is dangerous.

HOWEVER

AFAIK if you are badly stuck reduce the pressure to get the car going.

Don't drive far though. Drive safely and appropriately before going to the nearest garage and inflating your tyres to the correct pressure.

If I'm incorrect I apologies however that is my understanding.

The whole deflating thing only works on surfaces that you drop in to afaik like soft sand. It makes no sense to me to increase the foot print on a slippery hard-ish surface and the end result would be the opposite as the weight is distributed over an even larger area. It would only allow the tyre/car to slide more easy, but i could be wrong ofcourse.

johnos1984

Biglad wrote: »

The whole deflating thing only works on surfaces that you drop in to afaik like soft sand. It makes no sense to me to increase the foot print on a slippery hard-ish surface and the end result would be the opposite as the weight is distributed over an even larger area. It would only allow the tyre/car to slide more easy, but i could be wrong ofcourse.

I hadn't seen it done until my neighbours done it. It was soft snow on a hill out of the driveway. I was amazed how well it worked

I'd never do it on ice though, soft snow only.

As I said though, a last resort and straight to a garage after

Biglad

I hear you johnos, and if it get's somebody out of a hole, great. It's the people going around bosting that they deflated their tyres by 15psi and get around "grant" because of it that do my head in. I had one calling up to my house on Sunday last and he did not make it up my drive...

but43r

leeroybrown wrote: »

If you only have two winter tyres on the front end of an FWD car you're asking for trouble unless you're incredibly careful. They'll lull you into a false sense of security with the improved grip for acceleration, braking and turn in, then the rear end grip will eventually let go leaving you in a nasty spin.

You are right, braking would be very dangerous as the rear would be pushing car forward while the front wheels are trying to stop the car.

Then again think of the fun you could have in an empty car park It could be as good as driving RWD car...

johnos1984

Biglad wrote: »

I hear you johnos, and if it get's somebody out of a hole, great. It's the people going around bosting that they deflated their tyres by 15psi and get around "grant" because of it that do my head in. I had one calling up to my house on Sunday last and he did not make it up my drive...

You know this explains a lot to me.

I've passed an unusual amount of cars pulled in with punctures, blowouts and tyres leaving the rims in the past few days.......a nice B4 Legacy on the M7 today was one which sticks in my mind

As I say.....I know I'm repeating it a lot but Biglad it needs pointing out for the great unwashed still driving about in blissful ignorance, low pressure for an emergency only. INFLATE IT ASAP

dcmraad

johnos1984 wrote: »

You know this explains a lot to me.

I've passed an unusual amount of cars pulled in with punctures, blowouts and tyres leaving the rims in the past few days.......a nice B4 Legacy on the M7 today was one which sticks in my mind

As I say.....I know I'm repeating it a lot but Biglad it needs pointing out for the great unwashed still driving about in blissful ignorance, low pressure for an emergency only. INFLATE IT ASAP

I tried it at 15psi and it behaved the same as at 32psi so I pumped it.

I think the poster that suggested out of allignment could be on the money.

I will change the rear tyres tomorrow to match the fronts and see how it goes.

glaston

I got 4 second hand winter tyres for a 118d and I'm not too impressed.
Two pneumant 150 wintec (very good thread depth) on the back.
Continental TS810 on the front (decent thread depth).
4 bags of cement in the boot!
I know the Contis are probably a superior tyre but I figured the better thread depth should go on the back??

I dont need to drive too much at the moment but I took it out to test:

Conditions: Very slippy compact snow covered with about three inches of fresh snow (bit like the first test here).
On the flat: Fine, took off as expected, a bit of slip at first but then ran grand.
On a slight incline: Not good, lots of slip, felt like I was running the regular tyres tbh, had to reverse up and get a bit of a run, no good if I get stuck on a hill in traffic!!

Any suggestions? Anybody selling a Subaru?:pac:

johnos1984

Not being smart but have you tried moving off in second gear?

glaston

Yeah, tried that on the flat and incline (with a spectator to accurately judge wheel spin). Same result on the incline, got a bit more spin on the flat, dropped the revs to the point of cutting out!

(I had to use third to get a petrol FWD car moving the other day)

woody33

New tyres can need up to 500 miles on them (apparently) before they scrub off the slippy release agent needed to get them out of the manufactoring mould.

Stealthirl

did you check the tire pressure with a good gauge ?
u could try swaping the wheels around aswell ?

glaston

Tyre pressure was over 30 (probably about 34), I dropped it to 25 but no difference. I also tried with stability control turned off (i.e. dynamic traction control).

I have been driving with the tyres for the past few days in very cold icy conditions sometimes on roads with ice ridges, this was the first test in proper snow.

kennyb3

glaston wrote: »

I got 4 second hand winter tyres for a 118d and I'm not too impressed.
Two pneumant 150 wintec (very good thread depth) on the back.
Continental TS810 on the front (decent thread depth).
4 bags of cement in the boot!
I know the Contis are probably a superior tyre but I figured the better thread depth should go on the back??

I dont need to drive too much at the moment but I took it out to test:

Conditions: Very slippy compact snow covered with about three inches of fresh snow (bit like the first test here).
On the flat: Fine, took off as expected, a bit of slip at first but then ran grand.
On a slight incline: Not good, lots of slip, felt like I was running the regular tyres tbh, had to reverse up and get a bit of a run, no good if I get stuck on a hill in traffic!!

Any suggestions? Anybody selling a Subaru?:pac:

Dont mean to be bad sound like you got bad second hand tyres. I put 4 new dunlop 3d sports on my undriveable 3 series and it is now like a 4x4 with no weight in the boot. I ve been going evrywhere with no issues, even up big hills that plenty of fwd cars have got stuck on.

dcmraad

Hiya.

My new tyres are 10mm, and they are 8 ply, and run 55psi.

2nd winter tyres with 5 or 6 mm on them are not as effective at all, it looks like you have a lot of thread but you don't really.

glaston

Thread depth is 7mm, whats ply about??

I ve been going evrywhere with no issues, even up big hills that plenty of fwd cars have got stuck on.

Have you tried stopping on a hill or am I asking too much?

kennyb3

glaston wrote: »

Thread depth is 7mm, whats ply about??

Have you tried stopping on a hill or am I asking too much?

I have, i ve done plenty of hill start where other cars have had trouble and no problems. On one particularly icy slope i had to stop and it did take a few seconds to bite, with bit of spinning but i got up fine, all others the traction control light never even came on.

Compare that to 3 weeks ago when i couldnt get up a small hill out of my estate.

galwaytt

dcmraad wrote: »

I tried it at 15psi and it behaved the same as at 32psi so I pumped it.

I think the poster that suggested out of allignment could be on the money.

I will change the rear tyres tomorrow to match the fronts and see how it goes.

I'll wager the alignment is fine.

What you've done by having winter's on the front only is changed the slip angles on the different ends of the car: whereas they were both similar, and related, due to having the same types of tyre, you have now altered that, solely by tyre choice.

Consider, you previously had little/no grip at front, and car would understeer easily. Rear, therefore, had little/no influence.

However, now you have good grip on the front, but still the little/none at rear. Car now understeers far less at front.......which exposes the rear-wheel oversteer - all down to tyres.

dcmraad

galwaytt wrote: »

I'll wager the alignment is fine.

What you've done by having winter's on the front only is changed the slip angles on the different ends of the car: whereas they were both similar, and related, due to having the same types of tyre, you have now altered that, solely by tyre choice.

Consider, you previously had little/no grip at front, and car would understeer easily. Rear, therefore, had little/no influence.

However, now you have good grip on the front, but still the little/none at rear. Car now understeers far less at front.......which exposes the rear-wheel oversteer - all down to tyres.

Getting new rears fitted now

macnab

Its all down to physics.

If the grip is better on the front, then when you brake or slow down the rear will have more momentum so it will try to overtake the front (called swapping ends in racing speak)

The slowing down problems tend to be the case in front wheel drives more than RWD, as in the latter the rear wheels will loose momentum due to loss of drive/backlash etc.

JJJJNR

Thanks folks im here all day..

SouperComputer

Car is unbalanced, simple as. Given that you are generally sliding around in the snow a little anyway, the rear is going to be loose if its not proprtionally tyred to the front. You could try adding weight in the boot as a stopgap measure, its unlikely to balance it but it may make it a bit more stable.

biko

woody33 wrote: »

New tyres can need up to 500 miles on them (apparently) before they scrub off the slippy release agent needed to get them out of the manufactoring mould.

Shure nothing that a couple of burnouts on a dry road won't fix...

*I don't advice this