I agree with Rick that it's unclear how the error message relates to the problem you described. It sounds like you are able to ping across the lan link fine but it only fails when you ping across the GRE tunnel. You have the MTU set to 1476 on the CE tunnel int but not on the PE. Can you set the MTU to 1476 on the PE tunnel int 10013 as well and test?
It would be easier to know if it were normal if we knew exactly what debugs you had running and what version of IOS you were running.
This message on the CPE indicates that you did receive 3 packets over the tunnel, which would seem to be the icmp that you sent:
IP: s=10.36.85.146 (Tunnel1), d=10.36.85.145 (Tunnel1), len 100, rcvd 3
It is not clear whether you sent responses and if not why not. I assume that this debug was from debug ip packet on CPE. Are you running this debug also on PE? If not it would help to see that debug on both routers.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...