i think i have a problem...driveshafts

[blueb8llz]

for those of you that has a 3905, i suggest you guys check your center drive shafts as well. mine never twisted, but the allen screw, is always loose after every run!
so maybe its because the allen screw is loose, which causes it to twist. for some reason, its only the center driveshaft....all the other driveshafts screws never needs tightening.
the driveshaft im talking about, is the one where you tighten from the top of chassis (that little hole in front of the gearbox) i have the rpm center skid plate.

[JThiessen]

The reason for twisting center shafts is because it takes the largest amount of the torque. The grub screw has nothing to do with that. On yours, you should try replacing the end of the shaft, or put some loctite on it.