Transtar cabs

I understand the Transtars had real quality issues with their cabs cracking up. Does anyone know of the problems?

Remember some of them having a problem with the radiator hatch opening starting to crack and then spreading quickly outwards.
Also seen and heard of some where the pedestals that the cab tilt attached to the floor used to work loose and eventually punch holes through (the floor).
Both problems seemed to be more prevalent in the full sleeper cab (extra weight??) over the slimlines, although someone or other told me they used more alloy in the skinny cabs.
Dave

GM Diesel, member (ex) on here has one and I sourced a few bits form him, he was pleased to get the pedestals that seem to include the tilt hinges and other mounting bits. Apparently these were prone to cracking and excessive wear. Chocs is another missing member who would know the answers.

Cab construction from the parts manual.