Weird rear end issue. Fluid e'rwhere!

[Astro]

So, something weird going on at my rear end.

I went under there to mess with my body mounts and discovered a bunch of fluid residue on the fuel tank, the rear pumpkin, the exhaust, the axle housings, and the bottom of the bed.

Super confused. Touching the fluid, its kinda thick where it's not pooled, but thin where I found a drop. Come to think of it, it was thick only on the exhaust.

Also, annoyingly, it has no damned smell. It doesn't smell like gear oil. I checked my brake reservoir and its still full. I figured if it was the pinion seal, there would be a drop there, but there was only residue there, no drops or anything else.

Anyway, it's either brake fluid or rear end fluid, right?

How would you guys go about checking this?

 

[GoToGuy]

If it's being flung out , say pinon seal it should be in a centrifugal, pattern left to right. Use a white paper towel to sample for what color it is ? Regular gear lube has " that " smell. Check diff fluid level? Check axle vent tube/ line plugged.

 

[Astro]

If it's being flung out , say pinon seal it should be in a centrifugal, pattern left to right. Use a white paper towel to sample for what color it is ? Regular gear lube has " that " smell. Check diff fluid level? Check axle vent tube/ line plugged.

Thanks for your reply! I can't tell if it's being flung. But I guess it being everywhere sorta suggests that huh?

I'll have to pull the vent line off and check if it's clogged.

It looks almost clear, which made me think brake fluid, but the the brake fluid levels were still good in the master. Also, the paint on the bottom side of the bed isn't coming off, haha.

IDK man, I'm stumped. I went under there and tried cleaning it as best I could with brake cleaner.

 

[Hipster]

Taste test it lol

 

[Hipster]

Kidding aside, look around, stuff can be coming from something more forward and landing on the diff. Nothing dripping out of brake backing plates, tailhousing, front engine crossmember wet , blown oil cooler line, leaking oil filter or mount, blown rear main, etc,???? Check fluids, what's low?

 

[Astro]

Definitely haha! I looked everywhere and it's centralized around the rear end. Its annoying because as a band aid until I can afford to tear into it, I put a little stop leak in it for the drive shaft seals, but it looks like it broke it instead, lol.

I'm thinking I gotta change out the seal. I've been looking for info on how to retorque the nut after the change, but haven't been getting anything consistent.

 

[someotherguy]

Stop leak.

Richard

 

[evilunclegrimace]

Definitely haha! I looked everywhere and it's centralized around the rear end. Its annoying because as a band aid until I can afford to ear into it, I put a little stop leak in it for the drive shaft seals, but it looks like it broke it instead, lol.

I'm thinking I gotta change out the seal. I've been looking for info on how to retorque the nut after the change, but haven't been getting anything consistent.

The best band aid is to mark the pinion nut and the pinion. Count the number of threads showing above the nut, remove the nut,change the seal and retighten the nut back where it was and turn it just a bit more past your marks. It is not the correct way but it has been done many times to get a seal changed and out the door.

 

[GoToGuy]

I would crawl around under, what if there is a leak forward , and the airstream is carrying it back . The axle is big target.
Rear trans seal? Transfer case seals? Rear main? ATF cooling lines fittings? Power steering lines? Oil cooler lines, hose?
Something spilled leaking in bed?

 

[Astro]

Yeah I checked that initially when I discovered it. There's nothing else forward of the pumpkin. And some of the spots, for instance, just to the left on the part of the gas tank that's near the seal, couldn't have been done by anything forward of it.

I pressure washed the undercarriage yesterday and hopefully I'll get a little bit of a better idea of where it's coming from over the next few days.

Also was wondering about the vent being clogged. Do you guys think loading and lots of heat could force fluid out of the front seal if the vent is clogged? Might be a thing.

In addition to the counting threads and marking, I saw somehow measure rotational torque with a dial torque wrench as a way to verify it was the same before and after. Seems like a good addition or safety measure.

I really appreciate you guys giving me tips and some direction!