i have '85 6.9 w/ a c6 which has a gear vendor on that. is the c6 a 3 speed? if so i only get 1 more shift from the tranny unless they are too subtle for me to feel them. also on my gear vendor dash switch (manual/auto) i have an indicator light that works intermitantly on the auto side and has never worked on the manual side. why? also there is a seperate switch on the dash that supplies power to the gear vendor although it seems to work w/o this switch being on. any ideas? what about maintainance for the gear vendor. oil change? anything else? thanks alan

 

Well, the c6 automatic is a non- overdrive, hydromechanical transmission. The Transmission itself only has 3 gears yes: 1st, 2nd, and 3rd is direct drive. Never owned a gear vendors unit, but i know a small amount about them. Sounds like you are talking about the add on after market over-drive unit. It probably has a manual switch to take it out of overdrive so that you dont fry your tranny when towing a heavy load I would guess... Not sure what tranny fluid or oil it make take or when to change it. Hope this helps. Im thinking that there is probably someone on this site that has it so you can find out through them.

 

I have one of those not being used.. except it's a Doug Nash version for the C6.. it essentially gives you two speeds in each gear.

It probably uses something thick like 90w, but you should go to their website and find a manual.