katahdin_lubricants

This morning on way to work out of the blue the car jumped into neutral at 80mph. I shifted back into 5th and as soon as I gave it throttle it popped back out. I again put it back into 5th and put pressure on it. As soon as I gave it throttle I could feel it pushing back against me and it popped out of gear again. I shifted to 4th and left it. I called local GM dealership and talked to lead mechanic and told him what is going on. He doesn't think it's internal, told me to adjust shifter linkage and check roll pins. I swung into dealer after work and picked up roll pins and came home.
Now I've been trying to get the roll pins out but they won't budge. I'm afraid I'm going to have to drop tranny again (new clutch 3 weeks ago) to replace these damn things. If I knew about them I would have replaced them when tranny was sitting on my garage floor.
Now the lever has some vertical play in it, about 1/8-3/16" in any position. I've tried holding that up and tapping a new pin in, tapping with pin punch, even removed strut and hub and tried tapping from wheel well side. I cannot get these to budge.
If my tranny has to come out, is there an easy way to check 5th gear synchro behind that cover?
I'm beyond frustrated at this point....

Viperoni

I had to use a 5lb sledge to get enough force to knock my pins out, but I did it from the top (dropping the tranny a bit) and didn't have much room to swing. They do come out eventually.

katahdin_lubricants

I wound up pulling tranny. I had a broken bolt in front tranny mount that I couldn't Get out so off to the machine shop it went. Once it was on the floor the pins came out ok, they were bent so it took some effort to budge.