diff --git a/dumux/linear/seqsolverbackend.hh b/dumux/linear/seqsolverbackend.hh
index 103961b4b78a1cc5d7557a0e912a07d9f2461c95..17a120a71718179d81fb84a00b590b1e0bc16f45 100644
--- a/dumux/linear/seqsolverbackend.hh
+++ b/dumux/linear/seqsolverbackend.hh
@@ -52,95 +52,6 @@ class IterativePreconditionedSolverImpl
 {
 public:
 
-    template<class Preconditioner, class Solver, class SolverInterface, class Matrix, class Vector>
-    [[deprecated("Removed after 3.8. Use solver from istlsolvers.hh")]]
-    static bool solve(const SolverInterface& s, const Matrix& A, Vector& x, const Vector& b,
-                      const std::string& modelParamGroup = "")
-    {
-        Preconditioner precond(A, s.precondIter(), s.relaxation());
-
-        // make a linear operator from a matrix
-        using MatrixAdapter = Dune::MatrixAdapter<Matrix, Vector, Vector>;
-        MatrixAdapter linearOperator(A);
-
-        Solver solver(linearOperator, precond, s.residReduction(), s.maxIter(), s.verbosity());
-
-        Vector bTmp(b);
-
-        Dune::InverseOperatorResult result;
-        solver.apply(x, bTmp, result);
-
-        return result.converged;
-    }
-
-    template<class Preconditioner, class Solver, class SolverInterface, class Matrix, class Vector>
-    [[deprecated("Removed after 3.8. Use solver from istlsolvers.hh")]]
-    static bool solveWithGMRes(const SolverInterface& s, const Matrix& A, Vector& x, const Vector& b,
-                               const std::string& modelParamGroup = "")
-    {
-        // get the restart threshold
-        const int restartGMRes = getParamFromGroup<int>(modelParamGroup, "LinearSolver.GMResRestart", 10);
-
-        Preconditioner precond(A, s.precondIter(), s.relaxation());
-
-        // make a linear operator from a matrix
-        using MatrixAdapter = Dune::MatrixAdapter<Matrix, Vector, Vector>;
-        MatrixAdapter linearOperator(A);
-
-        Solver solver(linearOperator, precond, s.residReduction(), restartGMRes, s.maxIter(), s.verbosity());
-
-        Vector bTmp(b);
-
-        Dune::InverseOperatorResult result;
-        solver.apply(x, bTmp, result);
-
-        return result.converged;
-    }
-
-    template<class Preconditioner, class Solver, class SolverInterface, class Matrix, class Vector>
-    [[deprecated("Removed after 3.8. Use solver from istlsolvers.hh")]]
-    static bool solveWithILU0Prec(const SolverInterface& s, const Matrix& A, Vector& x, const Vector& b,
-                                  const std::string& modelParamGroup = "")
-    {
-        Preconditioner precond(A, s.relaxation());
-
-        using MatrixAdapter = Dune::MatrixAdapter<Matrix, Vector, Vector>;
-        MatrixAdapter operatorA(A);
-
-        Solver solver(operatorA, precond, s.residReduction(), s.maxIter(), s.verbosity());
-
-        Vector bTmp(b);
-
-        Dune::InverseOperatorResult result;
-        solver.apply(x, bTmp, result);
-
-        return result.converged;
-    }
-
-    // solve with RestartedGMRes (needs restartGMRes as additional argument)
-    template<class Preconditioner, class Solver, class SolverInterface, class Matrix, class Vector>
-    [[deprecated("Removed after 3.8. Use solver from istlsolvers.hh")]]
-    static bool solveWithILU0PrecGMRes(const SolverInterface& s, const Matrix& A, Vector& x, const Vector& b,
-                                       const std::string& modelParamGroup = "")
-    {
-        // get the restart threshold
-        const int restartGMRes = getParamFromGroup<int>(modelParamGroup, "LinearSolver.GMResRestart", 10);
-
-        Preconditioner precond(A, s.relaxation());
-
-        using MatrixAdapter = Dune::MatrixAdapter<Matrix, Vector, Vector>;
-        MatrixAdapter operatorA(A);
-
-        Solver solver(operatorA, precond, s.residReduction(), restartGMRes, s.maxIter(), s.verbosity());
-
-        Vector bTmp(b);
-
-        Dune::InverseOperatorResult result;
-        solver.apply(x, bTmp, result);
-
-        return result.converged;
-    }
-
     // solve with generic parameter tree
     template<class Preconditioner, class Solver, class Matrix, class Vector>
     static bool solveWithParamTree(const Matrix& A, Vector& x, const Vector& b,