Don't have a owners manual for my 1994dodge ram 2500 gas and would like to know where the four wheel drive fuse is which one it is.. I replaced the spider gears and everything and my four wheel Dr will not engage help
Your question says Dec 2018 so I don't know if you've had it repaired yet but I'd like to help. The 4x4 in your truck is not electronic but it has a light to tell you when it is engaged. Assuming the transfer case lever feels like it shifts okay when you go from 2wd-hi to 4wd hi, what you want to do is, 1)put the vehicle in park, leave truck in 2wd, key on engine off and parking brake on if it works. 2) Crawl under the truck from the passenger side and look at the front axle from the middle of the truck. There is a square, aluminum piece mounted to the axle with 2 vacuum lines going to it and an electrical connector hooked to it. 3) Unplug the electrical connector and jumper the 2 wires inside the harness while someone looks at your 4x4 light on the dash. The light should turn on. If it does then either the vacuum lines are rusted, plugged, unhooked, or the vacuum canister on the axle is bad.(Both are common) To test the vacuum canister you must have a vacuum hand pump tester or start the engine and feel the vacuum lines. One of them should have good suction at idle. They are bonded together but you can use the one with good vacuum by pushing it onto each vacuum nipple, one at a time to see if the axle engages. Remember to plug the electrical connector back in so you can see if the light comes on. That vacuum canister engages a slide lock to hook the inner axle to the outer axle. To see if it's working just jack the right front tire a couple inches off the ground and try to spin the tire. When it engages the front driveshaft will start to spin from spinning the tire. The truck being in 2wd and in park will stay put. DON"T LET ANYONE PUT IT IN GEAR WHILE YOU ARE UNDER IT!!! They also sell electronic axle actuator kits to eliminate the vacuum issue
Hope this helps.
1994 Dodge Ram...
on Mar 01, 2019