Solved by ptrblck in post #2 
              
              
                You can specify the kernel_size, stride, dilation, and padding for each dimension separately and using a single scalar value is a convenient way to set all dimensions to the same value. 
This should thus work: 
x = torch.randn(1,3,1,128,128).cuda()

layer = nn.ConvTranspose3d(
    in_channels=3,
   …