Sudden transmission failure

I have a 1997 RR 4.0, last night while driving on to the entrance ramp of the expressway, I excelerated very hard to gain speed to enter the road. At about 50mph, my veheicle slipped out of gear as if in neutral and remained. When I try to put the car in forward or revearse gear, nothing happens. I do get an "Gearbox Failure message" on the dashboard. I also noticed my "Check Engine" light stays on now. Any ideas?

Thanks

My former 97 4.0 SE did the same this winter. $2000 later and a rebuilt transmission and all is back to normal...........Kenny

Thanks, I think it's my transmission also....At least that's what the shop thinks....I will now more later today.

Any news on this ?

:confused:

I think that switching to synthetic fluid hastened the transmission's dermise. Of course I will never know the actual cause................................Kenny