Yellow/green fluid rear axle

[York]

During Sundays snowstorm while driving in 4A I noticed a strong sulfur smell. After parking and moving it the next morning I saw bright yellow drippings on the snow under the rear axle in the middle. Thinking it’s rear differential fluid. Anyone else experience this? At the dealer now. CHT says it’s definitely rear differential fluid fluid from M220 and a known issue.

Sponsored

 

[WarthogJr]

Looks like you peed in the snow and made up a story about it.

 

[York]

Bizarro response buddy.

 

[Brian_B]

Sure you don’t have stray dogs or cats in the neighborhood?

Sure it’s possible to be gear oil, but I wouldn't say rear end leaks are a common Bronco aliment - at least any more than any other RWD vehicle.

 

[HighVelocity]

What's it taste like?

 

[Brian_B]

What's it taste like?

This is really the only way to know.

 

[BlueWaffle]

This is really the only way to know.

A nice deep sniff would tell a guy..

 

[BobbySaggz]

I saw bright yellow drippings on the snow under the rear axle in the middle. Thinking it’s rear differential fluid. Anyone else experience this? At the dealer now.

CHT says it’s definitely rear differential fluid fluid from M220 and a known issue.

You saw evidence of a leak from a place that holds that color fluid. Did you look at the differential? Surely there would be an oily residue at the bottom of the diff, or around the cover mating surface.

I hope "CHT" isn't referring to ChatGPT or some other AI assistant, but I'm not holding my breath. You're 90% of the way there, but instead of using your eyes for a definitive answer, you ask a computer?

 

[PWillette]

During Sundays snowstorm while driving in 4A I noticed a strong sulfur smell. After parking and moving it the next morning I saw bright yellow drippings on the snow under the rear axle in the middle. Thinking it’s rear differential fluid. Anyone else experience this? At the dealer now. CHT says it’s definitely rear differential fluid fluid from M220 and a known issue.

Possible pinion seal leak. If it's dripping that much any residue should be pretty obvious.

 

[BroncoChallenger]

I'm not sure what's in the Bronco's rear axle, but I have never seen differential fluid that color, nor has it ever smelled like sulfur - and I've been around plenty of axles in my life and worked on more than my fair share. That looks more the color of antifreeze, but unless you have a coolant system leak it shouldn't be dripping from the rear axle.

Now, all that said, if they're using a different fluid in the rear axle now that I'm not familiar with, then yeah, it could be that. I would have crawled under the rig with a light and looked for an obvious fluid leak, as after sitting overnight that is quite a bit of fluid to have melted down into the snow like that.

 

[Brian_B]

Gear oil is usually either clear, or a very light brown when it's new. It tends to age toward gray/silver as it gets metal wear bits in it. It has a very distinctive odor, some may say sulfur although I wouldn't describe it as that.

Sulfur I would say would be more an indication of exhaust with an inadequate / failing catalytic converter or poor engine operation. It could also drip condensate that could be yellow or green in color. But to have that without a CEL or something else would be extremely unusual and it wouldn't be the first thing I would suspect.

Getting underneath and physically looking is the first step. If it's the rear diff the leak would be pretty obvious - oil residue where it's leaking, and if it's bad enough, it'll throw oil everywhere and it'll be a big mess -- just have to clean it off, then look shortly after cleaning to pin point the cause.

 

[BlueWaffle]

...nor has it ever smelled like sulfur

Just how much Colombian marching powder did you yeet up your nose back in the day? That shit'll ruin your sense of smell ya know..

I feel like I can smell gear lube through an unopened bottle it's disgusting.. and I've done my fair share of marching lol.

 

[BroncoChallenger]

Just how much Colombian marching powder did you yeet up your nose back in the day? That shit'll ruin your sense of smell ya know..

I feel like I can smell gear lube through an unopened bottle it's disgusting.. and I've done my fair share of marching lol.

I have never had it smell like sulfur. It does smell strong, but not like sulfur. I've been playing in various oils most of my life, and come across some smelly stuff, but I wouldn't call gear oil disgusting...just oily.

 

[VirginiaHeritage]

Getting underneath and physically looking is the first step.

Honestly, it’s something every Bronco owner should do on the regular, smells or no smells. Ford should throw in a Bronco branded creeper as standard equipment.

 

[helifino16]

Here's a picture of the dog expressing his opinion of the Bronco:

Sponsored