Haug, who had a long involvement in the DTM via his role at Mercedes, is concerned about the budgets required to run a team in the series and feels in-season testing is having a detrimental impact on the quality of racing.
“The DTM is still far too expensive," he told Bild. "There is far too much testing. That's a sustainability issue! You can't keep burning tyres and fuel senselessly in the future.
"I would abolish testing altogether, at most allow it on the simulator. Formula 1 doesn't test at all and the DTM does unlimited testing. So that can't be the right formula.
“Without testing, the races will be better and more exciting. There are more moments of surprise, the drivers are more decisive and more in the spotlight."
The DTM lifted its ban on private testing when it switched from Class One to production-based GT3 cars in 2021. GT3 cars are used in a wide variety of championships around the world, mostly with the same Pirelli tyres currently used in the DTM, thus making it difficult to regulate any running outside of race weekends.
At present, the top teams in the DTM hold 10 private test days per season, mostly at tracks that are already on the calendar.
Haug, who continues to attend every DTM race after retiring from Mercedes, is unimpressed by the amount of money teams spend to go testing every year.
"In some cases, ten sets of tyres - 40 tyres or even more - are used per car on a test day for short qualifying exercises," he said.
"A single day of testing costs 40,000 euros and more. That has no future.”
Based on Haug’s figures, a top team could be spending a total of 400,000 euros for 10 days of testing in a season. That could constitute a major amount of a team’s budget, which is estimated at 1.4 million euros per car.
A revamp of the current weekend format is currently being evaluated by the ADAC, which would help bring the costs down, following a meeting with the teams at the Red Bull Ring last month.
This would see qualifying being moved just before the race and practice being moved to Saturday, thus shortening the length of a DTM meeting from three days to two.
Haug feels the cost of running a team in the DTM would fall down considerably if teams have to take less equipment to each race weekend.
"I would also shorten the free practice sessions," he said. “Whether a race has to last 60 or 50 minutes is a different matter.
“If less equipment is needed, teams can travel to the tracks with two trucks instead of four, and half the fuel is used. The teams' overall budgets could drop by about 30 percent that way."
