We consider a class of SUSY models in which the MSSM gauge group is supplemented with a gauged U (1) B− L symmetry and a global U (1) R symmetry. This extension introduces only electrically neutral states, and the new SUSY partners effectively double the number of states in the neutralino sector that now includes a blino (from B− L) and singlino from a gauge singlet superfield. If the DM density is saturated by a LSP neutralino, the model yields quite a rich phenomenology depending on the DM composition. The LSP relic density constraint provides a lower bound on the stop and gluino masses of about 3 TeV and 4 TeV respectively, which is testable in the near future collider experiments such as HL-LHC. The chargino mass lies between 0.24 TeV and about 2.0 TeV, which can be tested based on the allowed decay channels. We also find 500 GeV, and 1 TeV. We identify chargino-neutralino coannihilation processes in the mass region 0. 24 TeV\(\lesssim {m} _ {{\tilde {\upchi}} _1^ 0}\approx {m} _ {{\tilde {\upchi}} _1^{\pm}}\lesssim\) 1. 5 TeV, and also coannihilation processes involving stau, selectron, smuon and sneutrinos for masses around 1 TeV. In addition, A 2 resonance solutions are found around 1 TeV, and H 2 and H 3 resonance solutions are also shown around 0.5 TeV and 1 TeV. Some of the A 2 resonance solutions with tan β≳ 20 may be tested by the A/H→ τ+ τ− LHC searches.. While the relic density constraint excludes the bino-like DM, it is still possible to realize higgsino, singlino and blino-like DM for various mass scales. We show that all these solutions will be tested in future direct detection experiments such as LUX-Zeplin and Xenon-nT.