I can say that my cherry tree is suffering from a fungus because of the cool, damp temps we've been having. Perhaps your tree will come back fine next year under more favorable growing conditions than we've had this year. I wouldn't necessarily blame the soil, mine are planted in clay too and one of them is doing fine....the other was a year end purchase at Lowe's and it has yet to do anything although it has been in for 4 years (it gets taller, no fruit or flowers).

Leaf curl is something I've experience on other trees and you can spray for that with dormant oil in the spring.

Your best bet IS to take in a branch with the fruit and the leaves still on it, and with leaves from the ground and to take it to your extension agency. They will be able to tell you what it is and what to do about it far better than we can guessing at the problems (temps, moisture, etc.) without a picture and without knowing the conditions your area has had.

I hope this helps.

michigoose, thank you for taking your time to reply quickly.
I broke my ankle bones 12 days ago when I was coming down the hill and it takes at least 4 weeks more to heal.
Yes, I am going to take leaves with fruits attached plus leaves fallen on the ground to PA State Extention office and let them check for me.
I am sure they are going to tell me what I need to do to save my two Asian pear trees.
Needless to say, they are going to give me information of exactly what kind of disease these trees have.

When I was in Japan, my family raised all kinds of fruit trees and Asian pears were one of them.
As far as I remember, my family never had any problem of Asian pear trees and every summer we had more than enough juicy sugar sweet, mouth watering pears.

I feel for you....in 2005 I moved to Ohio from CT. I thought I had clay in Ct....this soil is great for making pottery...and breaking my back.

I purchased a bunch of trees in late August, planning to plant them on the weekend. I went to my daughter's cross country meet on Saturday morning, and promptly broke a metatarsal....I had all these trees I had to sit and water for 10 weeks until my foot healed and I could dig, so I know exactly how frustrating it is!

Can you post pictures?

Jean001, here is picture.
http://plantpath.caes.uga.edu/extension/plants/woodyornamentals/PearEntomosporiumLeafSpot.html

Leaves of my two Asian pear trees are same as picture of leaves above.
Only difference is leaves of my Asian pear trees are curled.
Thank you for your concern.