2000 JIMMY SLS. Acceleration/Tranny Issue, help

Hello, first about the truck
Canadian 2000 JIMMY SLS, 99000 km. Auto, 4x4

I just went on an errand to the store, I was stopped at a light making a right hand turn. I accelerated around the corner when the issue happened.

I was accelerating moderately fast to get up to traffic speed. When the truck went to shift into second gear there was a loud clunk-pop, I lost power, the RPMs shot up and there was a loud 'spinning-whizzing' noise from the transmission area. It seemed it popped out of gear, exactly the same as what would happen if when driving a standard under hard acceleration you pull it out of first gear instead of shifting.
The 'whizzing-whirring' sound concerned me as I could hear it in the truck with the window slightly open., the noise slowed on its own.
This all happened within seconds, so I quickly put it in neutral then back in drive and i had power and drove to the store, except now it was really acting strange.
The whizzing-whirring sound stayed. And also now, the truck does not seem to shift until it is at 3-4000 rpm depending how quickly I accelerate. Around 20-30kmh or so. This is MUCH higher than normal.
Same after I stopped, at the store, and drove home.
I can't tell if it is missing second gear and going straight to third or is shifting late into second.
I drive in 1 and it had power. I stopped, put it in 2 and it went but did not seem to shift into second gear. I put it in 3rd and it downshifted same as it did in D. This was just a quick test though, I want to try the '2' test again to see if it shifts at all into second.

Also, if I engage 'TOW/HAUL' the RPM just shoot up.. nothing there.

so.... did I blow a tube? break second gear? blow a valve?

help, please.

Regards,
Cam

OK.. so I did more searching.. I do not have REVERSE either.. I think the tranny is f**'d.. based on what I have read elsewhere I am thinking the neck on the sun shell gear broke off.

Anyone have experiences or stories getting this fixed.??

Reverse,2nd. 4th lose is the weak leak in the 4L60E trans called the sun shell and at www.tciauto.com they show it and explain where it breaks at the small neck under the GM section. Here's the info:

New! 700R4/4L60E/4L65E Beast Sun Shell
Have you ever suddenly lost reverse, 2nd and 4th gears in your street machine? You're not the only one as the OEM sun shell assembly is a known weak point in the 700R4/4L60E. SPX Filtran has retooled the sun shell and improved it by making it thicker and revised the splined area that is prone to fatigue failure in the OEM parts. If you've got a heavy vehicle or an excess of 450 horsepower, the TCI® 373900 Beast sun shell is a cheap insurance policy against failure.