Ford 4500 industrial tractor common sump vent anywhere????

metalurge · May 2, 2019

Does anyone know if there is a vent somewhere for the rear end/ hydraulic sump on this tractor. I changed the brake rod boots the other day and noticed a sound similar to opening a soda bottle when I pulled the rubber boot off. Like it was a completely sealed system. I read a couple people mention that they had minor oil leaks on the rear axle seals on their ford 4000 tractors, and they thought it was probably due to the oil in the rear end heating up and having no place to go except out the seals. As if the system was not vented. My tractor does not use the common hydraulic / rear end sump to run the hydraulics. It uses the loader frame and a front mounted pump. I searched for a vent somewhere but could not find one.
My 3930 has a dipstick to check fluid levels. I assume that tractor could vent through it. The ford 4500 only has a pipe plug to remove to check the level of fluid. So is the 4500 rear end completely sealed off. I guess I could add a vent to the fill plug??? Maybe???

RickB · May 2, 2019

Some fill plugs have a vent in the side of one of the hexes that you would put a wrench on to remove. Some 3 cylinder tractors have a drilled bolt attaching the lift cover to the rear axle center section. I’ll check the Parts breakdown and post back later.

metalurge · May 2, 2019

RickB:
You steered me in the right direction. I checked the CNH parts diagrams for that tractor, and there it was!
I removed it from the top cover, and got that same whoosh sound again. Apparently there's two tiny holes drilled on the side of that little plug that were clogged. I had to drill them out. It took the tinyest drill bit I had. Hard to believe those two holes vent the entire hydraulic system and the rear end.
Thanks for the help