How many are using garden sprayers (the type you pump up) to change your drive oil? Or should I just use the old push pump on the 2.5 gallon jug.

thats what we use ( garden sprayer)

Us too ...........

the hand pump on a 5 gal bucket workes good for me

I rigged up a garden sprayer and it works like a champ.

how do you use the garden sprayer?

a tire valve mounted in the sprayer that you pump up with your air compressor works good and saves a lot of hand pumping

Yep. Same here with the garden sprayer.

Just cut off the metal end of the sprayer (leaving the valve intact, of course), zip-tie the clear plastic hose with the drive's screw-in fitting onto the end, and viola! And as mtgbiker mentioned, you can drill a hole into the canister and install a tire valve so you can fill it with compressed air and not have to pump. Works awesome.

Something like the pic below.

Oh, and this sprayer tool also works excellent for bleeding brakes on your truck!

slap the word "marine" on the side of that and market it for $64.99.

I use a 5 gallon bucket and the lid with a big pump on it....but my drives take 4.5 gallons each. It works quite well for me.