We present the universal form of η-symbols that can be applied to an arbitrary E d (d) exceptional field theory (EFT) up to d = 7. We then express the Y -tensor, which governs the gauge algebra of EFT, as a quadratic form of the η-symbols. The usual definition of the Y -tensor strongly depends on the dimension of the compactification torus while it is not the case for our Y -tensor. Furthermore, using the η-symbols, we propose a universal form of the linear section equation. In particular, in the SL(5) EFT, we explicitly show the equivalence to the known linear section equation. * The gauge algebra of the generalized diffeomorphism is closed if the following section conditions are satisfied [11,22]:where Ω IJ is the antisymmetric tensor intrinsic to the E 7(7) group. Under the section condition, all fields can depend on at most d coordinates (see [24] for a proof in the E 7(7) EFT).In the above conventional formulation, the Y -tensor and the section condition strongly depend on the dimension d, and when we consider applications of the E d(d) EFT, we need to specify the dimension d explicitly. A hypothetical "underlying EFT" (or 11D EFT), which reproduces all E d(d) EFTs (d ≤ 8) from simple truncations, has been proposed in [25], but the program has not been completed yet. In this paper, we investigate such uniform formulations from a different approach. In our approach, the Y -tensor is expressed in terms of SL(d) [or SL(d − 1)] tensors and E d(d) tensors are not used. Accordingly, the truncation to lower d can be easily performed.The present paper is organized as follows. In section 2, we introduce η-symbols as a natural generalization of the O(d, d)-invariant metric η IJ in DFT and explain how the η-symbols are related to branes in M-theory/type IIB theory. The Y -tensor is expressed by using the ηsymbols and the Ω-tensor. In section 3, we find the explicit form of the η-symbols and the Ω-tensor. In section 4, we show the explicit form of the section condition and the generalized Lie derivative. In section 5, we propose a new linear section equation, and show that it reproduces the known linear section equation [11] in the case of the SL(5) EFT. Section 6 is devoted to conclusions and discussion.