Changing car tires

[El Jeffo 42,118]

elattal comes from a country where they drive with their headlights off at night to improve mileage, so he must know what he's talking about.

[poohsan 2,486]

 

In older cars the speedo was driven by a cable directly from the gearbox output shaft. On newer cars the speedo can get its signals from one of the four "ABS Sensors" on each wheel. These sensors are actually called Phonic wheels.

 

They can but more likely than not they don't. the vehicle speed sensors that provides data to the speedometer are usually mounted on/inside the transmission on most newer cars.

[elattal 16]

 

elattal comes from a country where they drive with their headlights off at night to improve mileage, so he must know what he's talking about.

 

That's only when we run out of camel grains.

I give up on this discussion (it is also kind of off-topic). All I can say is that "most" of the information mentioned by all members is "relatively" correct. Appreciating everyone's eagerness to share his/her knowledge.

 

I am an automotive professional, but I don't claim I know everything. I just had to deal with speed sensors a lot :)

[elattal 16]

Further reading for whoever interested:

http://www.hotrodhotline.com/calibrating-speedometer#.U0xbovmSySo

http://books.google.com.eg/books?id=KZSbG-dVT3YC&printsec=frontcover&hl=de&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false (pp 55)

[HH_Sailor 3,529]

 

elattal: nope, they haven't done anything else but driving the car onto the elevator, pulling the winter wheels out, putting the summer wheels on, then driving it off the elevator. 57 euros in 5 minutes, I'm telling you IT is the wrong damn career.

 

I can only suggest that you shop around.

Local dealer advertises a "tyre hotel" and changes and stores for Eur 49,-

 

So I pay just short of 100 a year and twice a year they change wheels (I have winter rims as well as tyres).

 

To the folks who just drive and are not really up with the tech reasons

I have my 2c :

 

In winter - hang back and leave more space.

 

This whole "change the tyres depending on the season" smacks

to me of the German notion "find someone else to blame".

 

Of course the extra 3m braking distance could just perhaps maybe make a difference.

But changing driving style in icy conditions is IMHO far more successful.

 

I say all this living in the flatlands of north Germany.

 

In the Alps there could well be different experiences :rolleyes:

[Rankersbo 462]

 

horse shit...

 

The speed sensors are usually on the drive shafts..

 

Exactly, they measure the angular speed of the shaft not the forward velocity of the vehicle. With lower diameter winter tyres your car moves a shorter distance per rev of the drive shaft than with summer tyres.

 

AIUI recalibration isn't usually done, you just clock up more miles and your speedo reads higher over winter.

[murphaph 9,638]

 

For the ones complaining about the price, you can change the wheels yourself, it takes no more than one hour. And if you are lazy and/or weak you can invest in some tools, a good jack costs like 40 or 50 EUR and a torque wrench (Drehmomentschlüssel) another 20 or 30 EUR and you have equipment to do it without sweating.

A torque wrench for tightening up wheel nuts? I've put countless wheels on countless cars and never in my life have I used a torque wrench for it. The wheel brace that comes with the car is fine, but a decent trolley jack is a worthwhile investment alright.

[HH_Sailor 3,529]

I disagree...

 

The "wheelbrace" supplied with my car is only slightly longer than my hand.

I need more length (!) to get any torque applied.

 

A bit of pipe is OK so long as I am at home.

The torque wrench is a useful investment.

 

Putting all my not inconsiderable weight on the short spanner (by standing on it)

is not only dangerous if it slips, its also damaging to those

silly "key / lock" nuts.

 

BTW

Alu rims for summer and steel for winter?

The spare is probably steel too.

Don't forgt to keep a set of correct bolts** in the boot

next to the spare in case you have to change a flat during the season.

 

**if you have bolts and not just wheel nuts

[Grizzlor 157]

The use of a torque wrench is to ensure you don't over tighten, as opposed to helping you add more torque when tightening.

Over tightening can lead to dry welded taper surfaces, stretched studs (ooo-er missus) which can snap later when driving, increased play between nut and stud etc etc.

 

The classic pipe over shorter handled tool is much more likely to increases ones chances of over tightening, as the force you apply will feel less, but due to the increased radius you're putting a lot more torque onto the nut.

 

Having said that I've never experienced any of the above symptoms when I've not had a torque wrench available... but seeing as I do when swapping the wheels out at home, its as simple as checking manufacturer torque settings and apply them accordingly - as they'll be doing in a garage when you get them to swap them for you.

[Allershausen 6,414]

 

 

BTW

Alu rims for summer and steel for winter?

The spare is probably steel too.

Don't forgt to keep a set of correct bolts** in the boot

next to the spare in case you have to change a flat during the season.

 

**if you have bolts and not just wheel nuts

 

Some cars are required to have alloy wheels for winter tyres too, it's to do wth the brake cooling I believe. It will tell you in the Fahrzeugschein along with the size requirements.

If it has a spare, which many cars don't nowadays, it's probably a space saver which is speed restricted.

Some cars do require different bolts for steel or alloy wheels, for some reason French cars seem to, but most don't and certainly won't for a space saver.

Oh and it is very unlikely that the total diameter of a winter tyre is any more or less than the summer tyre. The wheels may be a smaller diameter, but the sidewalls are much higher (a higher aspect ratio, a calculation based on a percentage of the width of the tyre), thus giving you the same overall diameter, give or take a few millimeters.

[scoffer 440]

 

elattal comes from a country where they drive with their headlights off at night to improve mileage, so he must know what he's talking about.

 

Cool. Until I checked I mentally deleted the middle three letters and assumed he came from a country with an airline that didn't put its lights on at night to avoid being hit by surface to air missiles. How wrong can you be?

[DanglingPointer 29]

When do we change back to summer tires? End of March?

[Krieg 14,917]

O bis O = Ostern bis Oktober

[kaffeemitmilch 1,294]

11 minutes ago, DanglingPointer said:

When do we change back to summer tires? End of March?

 

There's no fixed date. You're just required to have the right tires for the conditions, so people go with the general rule of thumb and change tires in April and October. If the weather remains cold then you are basically expected to keep winter tires on as long as necessary, and if it gets cold early, put them on.

 

I have all-weather tires now, so I'm glad I don't have to deal with this (though I do have to rotate my tires).

[klingklang77 490]

In Munich I always change them around May (it always seems to snow once when you think it is finally spring). But I usually call them and they are booked so it tends to be the end of May. I skipped a year and drove around with winter tires all year. I know that’s not the best, but I have had the same car for 4 years and only put on about 8,000km, so that gives you an idea of how much I drive. 

 

I am planning on getting all weather tires when I move and lease a new car. 

[fraufruit 41,928]

We are selling the new summer tires that came on our new car and replacing them with all weather ones.

 

Looks like this is a good time to sell them since people will be changing.

[kaffeemitmilch 1,294]

I would have thought people in Munich would want winter tires given it's colder and closer to the mountains. Frankfurt is much warmer being in the Rhine/Main depression, so makes sense for us if we don't go to much colder climes that often. Winter tires are much better for real winter conditions.

[fraufruit 41,928]

We don't go in the mountains in snowy, icy weather. 

[yesterday 1,979]

Cannot really think of a day that you needed winter tires in the Munich area + Mountains this year, but of course I change them when I think I should

 

Cue Global warming

[Gambatte 897]

2 hours ago, fraufruit said:

We are selling the new summer tires that came on our new car and replacing them with all weather ones.

Looks like this is a good time to sell them since people will be changing.

This is interesting.

I hear a lot about people wanting to sell tires. I think unless the tires are not brand new, and yours obviously aren't, you can only sell them for next to zero.

After I had my car written off after an accident and I was left with the other 4 tires (including rims), I sold them on eBay for 5eur (=1.25eur each).

Please do tell us how much you sell them for, I'm curious.

In any case good luck.