When I first came on these boards I had a issue with performing tracert. I managed to find the problem, but it took some work. Recently, I found a super easy work around. Instead of
tracert google.com
just use
tracert -d google.com
I guess the issue isn't the ICMP packets but the name discovery the router is trying to perform from the packet responses. Turn that off, and quick as lightening. Useful when just looking for latency spikes. Cheers.