(NBC News) Open any trunk on many late model cars offered today and chances are you'll be surprised to discover there's no spare tire.
There may be a spot for the spare to fit in the trunk, but more and more automakers have gotten rid of the spare.
Automotive experts at Edmunds.com estimate a third of new cars do not have a spare because they've been focusing on something else.
"Carmakers started looking at getting rid of first the full sized spare, and then the temporary smaller spare tire, in order to make room for stuff, and to reduce the weight of the car," explains Carroll Lachnit of Edmunds.com.
Reducing the weight improves fuel efficiency.
Automakers also had research showing most motorists called for roadside assistance to fix a flat, even when there was a spare in the trunk.
GM and other manufacturers are putting a tire repair kid in place of spares.
They're portable air compressors loaded with a sealant that can fix some flats enough to get to a garage, but the key is knowing what's offered before you buy.
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