Oil-Trans. Shift-Tunnel
 

Going with a Short-shifter & new bushings.. I would like to know how much Oil to put in the shift - tunnel ? And would you use ;Tranny oil or gear oil ?

I had the same question last year. https://www.rx7club.com/3rd-generati.../#post12245511

80 - 95 mL (2.7 - 3.2 oz), and you can use the same 75w90 that you would fill the transmission with. Any fluid that goes into the shifter "turret" as it's called will stay separate from the fluid that lubricates your gears and etc. Note that you'll have to suction out any old fluid that might be in the turret unless you've recently disassembled your transmission.

A nice 5$ 200ml syringe works great for this with a small rubber hose attached. They can be found on Amazon.

Good luck!
-M

Personally I wouldn’t bother with siphoning the old gear oil unless it’s been contaminated somehow, or if/ when the transmission is ever dropped. You're messing with gear oil INSIDE the car. There’s little load on it, it stinks and there’s not much chance of successful clean-up if it’s dripped or spilled. Just don’t forget the grease per the FSM. My .02.

I'll take the old oil out of the [turret] I'm changing the tranny oil also and wondered if the second plug , not the fill plug, the one down from it might drain the turret ? thanks for the help; I like to get it right ,the first time ! Brian

I agree. And a step in that direction is to look at a copy of the Factory Service Manual. Free down load in the FAQ sticky.
The 75w-90 gear oil contained in the shifter reservoir is isolated from the rest of the transmission. As such it won’t drain from either drain plug and must be siphoned if it’s to be removed. Changing the 75w-90 gear oil in the transmission is a wholly separate operation. But the good news is that since those parts submerged in the reservoir are not under load (wear) or subject to typical contamination or heat, there’s very little reason to change it. If you’re just adding a short shifter, CAREFULLY remove the stock assembly, grease the ball and lower bushing of the new per the FSM and install. Done.