SOLVED: FW #716: Metzeler tire-test-truck by Kässbohrer, Büssing TU5000 based, 1956

[fromwien]

Please be so kind and identify this vehicle and what purpose it was built for

[Trip]

Kässbohrer truck for testing Metzeler tires?

[fromwien]

Great! You are very near to complete the solution:
Yes, the bodywork of this truck came from Kässbohrer. The purpose the truck has been built for, was tire testing. In this case for Metzeler.
What's still remaining to complete the answer:
1) What was the base of the truck?
2) When?
3) Furthermore there was a nickname for this vehicle..
I feel sure, you will find the answers easily.
LOCKED for 'Trip'

[Trip]

1) Büssing TU 11
2) 1956
3) The Elephant

[fromwien]

1) Büssing TU 11
2) 1956
3) The Elephant

ad 1) I know, that some sources mention 'Büssing TU11' as base chassis of this vehicle. My source claims that it is a different Büssing chassis.
ad 2) 1956: correct
ad 3) One word missing: 'The ....... Elephant'

[Trip]

Büssing TU 7? The white elephant?

[fromwien]

TU is correct, but an older one than 7 or 11
Not 'the white elephant', but an elephant how he can't do in nature

[Trip]

Is it just a TU? And if the elephant isn't white maybe it's pink?

[fromwien]

Is it just a TU? And if the elephant isn't white maybe it's pink?

It's TU, followed by some digits
The missing word we are searching for of the nickname doesn't relate with the colour of the elephant

[Trip]

TU 5000, the flying elephant.

[fromwien]

Exactly! Congratulation to your second point! Keep on puzzling!

[Trip]

Thank you so much! 

[Wendax]

In total, four of these tire test vehicles were built differing in details: one for Veith B. F. Goodrich, two for Fulda and the one for Metzeler.

[fromwien]

Photos of the Fulda- and Veith B. F. Goodrich-tire test vehicles