I\'ve been unsuccessful in getting Emacs to switch from 8 space tabs to 4 space tabs when pressing the TAB in buffers with the major mode text-mode.
(customize-variable (quote tab-stop-list))
or add tab-stop-list entry to custom-set-variables in .emacs file:
(custom-set-variables
;; custom-set-variables was added by Custom.
;; If you edit it by hand, you could mess it up, so be careful.
;; Your init file should contain only one such instance.
;; If there is more than one, they won't work right.
'(tab-stop-list (quote (4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120))))