Simple setup for filling trans fluid

[SS_Dave]

Sometimes the simplest stuff makes a huge difference. Threw this together today to refill trans fluid. Super simple. Worked great. Didn't spill any. Highly recommend. Funnel was just the right size to sit up top in engine bay and dump a full quart of Synchromesh, then go below and open the valve. Repeat for all four and on the last one just lift the line a little to empty it all in. Simple is good.

It's just a sprinkler valve, some tubing and a funnel.

[J35Y2]

I had trouble posting photos, but I got this huge plastic pail siphon. One of the ends threads into the pail, and the other port by the “t”-shaped handle, is for the pail feed to siphon the output. I usually get a whole 4-5 qts/L’s filled into the trans (or whatever else), in roughly 6-8 full pumps of the handle.

They sell it at Autozone, and the siphon includes only one clear hose. I haven’t measured the diameter, but it’s probably 1/2” or wider. Problem with this method, is that you have to use hose clamps or spring clamps on the hoses, and the plastic degrades over time from either pumping ATF or gear oil through it.

O’Reilly recently started stocking 2 other siphon pumps, which are made of metal and seem to have bigger adapters for the ports/hoses. Looks like this pumps might be a little more efficient than the common style siphon pumps, with the pump having 2 threaded cap ends. Problem I have with the coiled up hosing/tubing that comes with the common style siphon pump, is that the hose either coils up or kinks when I don’t want it too; or the hose is simply too stiff and I can’t get it to move properly to where I want it to go (usually inside of a quart or gallon container.

Also, I tend to change the trans fluid with only the front end lifted up off of the ground (with rear wheels fully chocked off). This helps the drain port empty out more efficiently, due to the angle. However, the angle causes the trans to be under-filled, if you simply stop pumping/siphoning fluid into the fill port, as soon as it starts overflowing or dribbling out.

To counteract this, I usually have an extra 0.25-0.5 qt of trans fluid, and I “overfill” the trans (yes, literally). If you don’t do this while the front end is up, you’ll notice the transmission shifting poorly once you finish filling, since there’s not enough fluid circulating around in it. I usually try to get anywhere from 4.25-4.5 qts out through my pump, before I yank out the hose from the fill port, as quickly as I can. You have to pretty much close the fill port as quickly as possible, but I usually try not to lose too much fluid. Seems like over-filling a small amount does more good in my case anyways.