Spare wheel

[Buckman]

The spare wheel on our wheel is identical to the road tyres in all aspects except the width. The actual road tyres are 20" but the width of the spare tyre is 18". It is the same size as the tyres fitted to the basic version of the same vehicle so not exactly a space saver. As it is a normal tyre there is a speed limit printed on the tyre and it is well in excess of 50mph the limit for many space savers. Am I still limited to 50mph if using the spare and is there an issue with towing?

In addition, the spare is secure in the rear well under the boot lining and has not seen daylight and has never been used however it is now over 8 years old. I am guessing that there would be no need to change this tyre for another several years as it looks like brand new all round.

 

[otherclive]

The spare wheel on our wheel is identical to the road tyres in all aspects except the width. The actual road tyres are 20" but the width of the spare tyre is 18". It is the same size as the tyres fitted to the basic version of the same vehicle so not exactly a space saver. As it is a normal tyre there is a speed limit printed on the tyre and it is well in excess of 50mph the limit for many space savers. Am I still limited to 50mph if using the spare and is there an issue with towing?

In addition, the spare is secure in the rear well under the boot lining and has not seen daylight and has never been used however it is now over 8 years old. I am guessing that there would be no need to change this tyre for another several years as it looks like brand new all round.

It’s a quite contentious issue this one of “ non standard” or space saver spares. I’ve had cars where the manual says nothing, and some where it says put it on the rear. I tend to the view that the OEM spare is designed to take the cars load and it doesn’t know how that load is applied. For a normal space saver I would put it to the rear solo or towing then the cars steering characteristic is less affected. As per speed if it’s not stamped as 50 mph then presumably a higher speed could be used. But to be honest what’s the real difference between towing at 50 mph or 60 mph when a spare is fitted? Not a great deal.
Regarding life of a spare I’ve seen periods between 7-10 years. I use tyre dressing or Armorall about twice a year but wouldn’t extend life beyond 10 years if unused. But that’s just me.

 

[Beachball]

My spare wheel is same size as the ones fitted to the car but that is 2 years old now .

 

[ProfJohnL]

Quite simply you have to be guided by the car manufacturer's instructions in their handbook, and any information on the spare wheel itself. As OC points out the tyre does not know how the load its carries is created, so unless the car or tyre manufacturer specifically excludes towing, then it should be permissible.

Having said that, most space savers have a restricted driving range, and a maximum speed. Im also sure they smaller footprint of the tyre will have significantly reduced grip and increased wear so it really only used to get the vehicle to a tyre repair center.

 

[Buckman]

Quite simply you have to be guided by the car manufacturer's instructions in their handbook, and any information on the spare wheel itself. As OC points out the tyre does not know how the load its carries is created, so unless the car or tyre manufacturer specifically excludes towing, then it should be permissible.

Having said that, most space savers have a restricted driving range, and a maximum speed. Im also sure they smaller footprint of the tyre will have significantly reduced grip and increased wear so it really only used to get the vehicle to a tyre repair center.

As a matter of interest won't the load rating be on the tyre even a space saver? Obviously our spare as it is a normal tyre has a load rating of probably 500kg.

 

[otherclive]

Looking at the suppliers of space saver tyres they quote load ratings which vary between tyres sizes.

 

[JezzerB]

As this isn't a space saver it probably isn't necessary to stick to 50mph; for minis for example you can have 15,16 ,17 ,18 inch rims with tyres of different profiles so th e rolling circumference is exactly the same-this way the speedo and miles read correctly. If this applies to your tyre then you can drive to the speed limits BUT if the profile means the car isn't sitting straight I wouldn't exceed 50mph anyway to be on the safe side-as all the others have said-doesn't make much difference anyway does it tbh? HOWEVER as per Clive 10 years would be the absolute limit for me for any tyre on any road vehicle and earlier preferably-I'd be keeping a close eye for tyre wall or tread cracks after 7 years old tbh. Wouldn't want to risk a blow out.

 

[otherclive]

As this isn't a space saver it probably isn't necessary to stick to 50mph; for minis for example you can have 15,16 ,17 ,18 inch rims with tyres of different profiles so th e rolling circumference is exactly the same-this way the speedo and miles read correctly. If this applies to your tyre then you can drive to the speed limits BUT if the profile means the car isn't sitting straight I wouldn't exceed 50mph anyway to be on the safe side-as all the others have said-doesn't make much difference anyway does it tbh? HOWEVER as per Clive 10 years would be the absolute limit for me for any tyre on any road vehicle and earlier preferably-I'd be keeping a close eye for tyre wall or tread cracks after 7 years old tbh. Wouldn't want to risk a blow out.

Agreed I would only keep an unused and stored spare up to 10 years. Road tyres on cars like you never more than 7 years. But generally they are down to 3 mm before then anyway.

 

[ProfJohnL]

As a matter of interest won't the load rating be on the tyre even a space saver?

I believe every road tyre sold lawfully has to include the manufacturers name, size, manufactured date, speed and load rating. If the car manufacturer supplies a spare with a vehicle, then they must also supply any additional fitting and usage limitations in the owners manual. If the manufacturer does not instruct any reduction in load, then the supplied spare should be able to handle all of the cars loads within its specification.

As with all vehicle maintenance and usage, it is up to the driver to ensure no limits are exceeded and that replacement parts encompass the specification for the standard vehicle.