Abstract. The SL(3) Kuznetsov formula exists in several versions, and has been employed with some success to study automorphic forms on SL(3). In each version, the weight functions on the geometric side are given by multiple integrals with complicated oscillating factors; this is the primary obstruction to its use. By describing them as solutions to systems of differential equations, we give power series and Mellin-Barnes integral representations of minimal dimension for these weight functions. This completes the role of harmonic analysis on symmetric spaces on the geometric side of the Kuznetsov formula, so that further study may be done through classical analytic techniques.The classical Kuznetsov formulas serve as a bridge between Fourier coefficients of Maass forms and Kloosterman sums. They are a necessary step in most proofs of subconvexity for Lfunctions, in a variety of equidistribution problems, in proofs of bounds and asymptotics for Maass forms, and in many applications of the circle method to problems in additive number theory. In attempting to generalize the Kuznetsov formula to study Fourier coefficents of SL(3) Maass forms, we encounter difficulties due to the lack of knowledge of the generalized Bessel functions that appear. The goal of this paper is to solve those difficulties for the spectral Kuznetsov formula.There are essentially four versions of the spectral Kuznetsov formula: The first, due to Xiaoqing Li, appears in [9, Thm 11.6.19] and uses an idea of Don Zagier with bi-K invariant test functions and spherical inversion. The second, due to Valentin Blomer, appears in [3] and uses the classical construction with the inner product of two Poincaré series. In [10], Dorian Goldfeld and Alex Kontorovich applied Lebedev-Whittaker inversion to Blomer's construction to obtain an arbitrary test function on the spectrum. Finally, in [7], the author worked out the first part of the integral transform on the geometric side of Li's version to obtain a slightly more usable formula -the main thrust there being an approximation to the geometric Kuznetsov formula.These four versions have been used with varying degrees of success. Li was able to obtain some results on spectral averages of the 1, 1 Fourier coefficients of cusp forms, weighted by their Whittaker functions [12]. Blomer has given a non-optimal version of the spectral large sieve inequalities and Lindelöf on average for the second moment of SL(3) L-functions [3]. Blomer, Raulf, and the author have given results on the distribution of the Fourier coefficients of SL(3) forms, including a Sato-Tate law on average [4].