Tires: Damage to transmission due to different tire sizes, wheel drive car, tire guy

Question
QUESTION: If a front wheel drive car has different tire sizes on the two front wheels can this cause damage to the transmission?

ANSWER: Herman,

It might cause damage and it might not.  It might cause some additional wear, however, most of the time no harm is done.   

And, of course, the liklihood is dependent on many factors including how different the tire sizes are.

---------- FOLLOW-UP ----------

QUESTION: A tire was damaged and replaced under warranty by the tire dealer.  They put on a larger tire by mistake and put it on the front of a front wheel drive Acura.  A few weeks later the transmission failed and was very costly to replace.  I think that they will take responsibility for their error if I can give them an authoritative statement that driving for several hundred miles can damage at transmission.  I recall that use of a small "donut" spare tire should not exceed 50 miles.  Is that correct?  Can you give me a link to a site that says this?  Thanks.

Answer
Herman,

Looking at it from different perspectives:

1)  If the transmission failed, then you'll need someone to say that there was damage as a result of something related to the differential part of the transmission - and not an internal part of the transmission that is involved in gear selection and the like.  Needless to say, the amount of miles on the differential and the maintenance practices are going to play a role here.  

2)  The "50 miles" is a limitation for the tire and not for the transmission - and in particular, the differential.

My advice:  See if they will "pony up" just based on the circumstances.  Otherwise, you are looking at getting a failure analysis of the transmission - and a statement from a tire guy whose expertise is not transmissions isn't going to help you much.