I recently purchased a rebuilt turbo for my 1986 300SDL.

I had my certified mercedes mechanic remove hte old and install the new.

The previous turbo has seized.

As is required a new oil line was installed, and oil pump checked for proper operation.

While drive on the freeway at 70mph, the turbo failed. I immediately drove to my mechanic. There was a "rattling" noice coming from the turbo. After the turbo cooled he removed it. Upon inspection he found the inner shaft to have been snapped in two. There was no smell of burnt oil, there was a large amount of oil inside the turbo, and when the engine was cranked a proper amount of oil flowed from the oil line.

When the rebuilder recieved the turbo, he pointed the finger at the car and the mechanic, saying that either the mechanic installed it improperly ie: didnt use new oil line or the oil pump was not working properly. That the lack of oil was the only reason a failure as mentioned above could have occured. He stated this was further established as the break in the "shaft" was exactly at the point oil came into the turbo.
(not sure what,if anything, this has to do with it, but he said it did).

My problem as you can see if that I am caught in the middle here, and havent a clue what to believe. My mechanic stood to make more money if he stated my oil pump need to be replaced, but stands firm that it is operating properly and is strong. He says the "shaft" was faulty or the turbo wasnt rebuilt properly.

The Turbo rebuilder says if he has to replace the turbo this time, he will NOT warranty it further (not sure he can legally do this if the car was an is operating under proper spec's).

I dont want the turbo to fail again, and am not sure what to do here. Do I replace an oil pump my mechanic says if functioning properly just to appease the turbo rebuilder?

Can anyone offer me some advice? Has anyone had this problem? Anyone familiar with the inner workings of turbos?

Thanks,
Chris