I have an 87 Lull Highlander 844 I use for masonry. I recently bought it, and I know this issue when I purchased it. The issue is it leaks spouts tranny fluid when in gear out of this little module on the upper part of tranny. Any ideas on the part this is, and how easy it is to fix? My first lift, and other than this its in great shape. 500 hours on new JD diesel and rebuilt tranny. This tranny fluid issue needs to be fixed though. In 3 days of use it will spout out so much it needs to be refilled. I've got a pic of it. Its got what feels like a rubber bulb on the end, and two wires going to it.
It looks and sounds like a pressure switch/sender. Guessing that end is a breather to outside pressure and the diaphragm is leaking inside the round crimped part. Take it off and plug the hole until you can get a new one. There might be numbers on there that will help you look up a replacement, or you might find a parts manual etc from Lull. Your choice whether you try to use it with the port plugged, you could disconnect the wires and see if one of the gauges (transmission pressure?) is affected to see how vital it is.
Thanks Delmer. What part of WI, you from?
What is the manufacturer and model # of the transmission in your 844?