Goin to be reinstalling the vss gear soon, and going to drain and fill the trans. Would be ok to refill via the vss gear hole? Seems like it would be much easier to refill from there versus a vertical fill.
Nobody has commented so here goes: Automatic, or manual? 4 Wheel drive? if 4WD, the speedo cable will be behind the transfer case. Trying to remember, but I think the automatics use motor oil for the transfer case and ATF in the tranny. If it's a 2wd and automatic, you should be okay (maybe, I've never tried it). If it's a manual, I think you can get away with it. FWIW, I have refilled several manual trannies with a small hand pump oil can. Takes forever, and you get a good grip workout. For automatics and the NO DIPSTICK, many have put a pan under the fill area and run a small clear plastic hose into the fill hole and then up the right fender to a higher spot and filled with a small funnel. STUPID DESIGN. Dennis
The VSS on a 2WD 4L30e is not actually mounted to the transmission, it is mounted to the transmission extension housing so you cannot refill as you suggest. Buy a pump and pump it in or use a long hose and a funnel. Be aware that the ATF level is only correct when is up to the top of fill hole with the engine running and the ATF warm to the touch.
The Motive pump I use can be pressurized so all you have to do is open the valve to transfer the ATF.
that pump is nice, but not likely inexpensive.
I have had got results using a cheap bug sprayer pump from the home center.
my first attempt involved cutting the spray nozzle off and using heat to shape the tube in to a hook shape to allow insertion.....that didnt work
What did work was a short section of steel brake line bent in to that hook and clamped on the the hose.
I use this Fumoto mini ball valve along with the pressure pump. Pump in extra ATF with pump when you fill up. Disconnect the pump shut the ball valve and start the engine. When the ATF is warm open the ball valve and drain off the extra into bucket. When the extra is drained off remove the ball valve and install the fill plug. No mess to clean up.
The valve is a Fumoto 106-N, about 25 bucks on amazon. I added an 14mm extension to the valve for clearance. The same valve will fit in the engine drain oil. You could leave the valve installed for quick oil changes if you wanted to flush the engine.
I remember when those valves became popular in the import car scene a few decades ago. The big fear of course, was leaving one installed and hitting something that could break it off while driving and dump all your oil.