So, my dad was rotating the tires today on his 2000 F150 to get it ready for a long camping trip and noticed some serious rust on his rear axle tube. Hadn't noticed it before because there's zero rust anywhere else on the truck. Never been in the salt. 75K miles.
Would this amount of rust concern you pulling a 5000 pound camper about 1000 miles?

 

It probably would't worry me, but without seeing it in person, who knows. If it is structurally sound, I'd probably wire brush it and smear the major pits with JB weld and brush paint the axle. You could just coat the axle with oil to stop the rust, but it'll be hard to tell if it starts leaking.

 

Serving suggestion:

1) Join Auto Club (AAA) if you are not already a member. Buy the maximum towing coverage.

2) Keep an eye on it during your trip. If it starts to leak, see number 1.

3) Replace the entire axle when you get back.

Alternate:

Pull the axle shaft and look inside. See if this is a dent or ding in the tube, and if so, see if it is still the same thickness as the rest of the axle. If there is no ding, I would expect this to be very thin where that crater of rust is.

 

I think I would PECK around with a welding hammer ( pointed ) and see how strong the metal in the PIT is..... I think I would chip off as much rust as I could, then wire brush to get 80% off........ then paint a RUST CONVERTER over the entire axle.. it will react chemically and form a black oxide hard surface........ then paint that with something like rustoleum..... you could fill the PIT with jb weld, but I would be temped to NOT fill and monitor for a drip in the future..... after dinging it several times with a chipping ( welding) hammer.

 

https://www.theruststore.com/rust-co...-faqs-w48.aspx

 

clean it up. weld a 1/8" steel patch over it, paint and call it a night.

 

It almost looks like something hit it and dinged in a dent.

 

I agree. It is not possible to gouge out that much metal without puncturing thru. You can verify it by pulling the axle and inspecting inside.

+1
Rust converter followed by a top coat.

 

Thanks for the input guys. I believe we'll clean it up, coat it, and head out.

 

I'd be interested to see an updated picture after you get it cleaned up, just to see what's under the crud.