Rear axle cracks/rust at corner or bushing arm (w/ pics)

Any competent welder could fix that but it may need removing to weld. Having removed the axle it would probably be quicker and cheaper to replace it with one from a front end damaged vehicle having obtained the part first.
The replacement axle should be scrubbed down and given a few coats of paint to avoid the problem again.

John (Britprius)

 

In structural engineering terms, this form of metal fatigue is called "stress corrosion cracking."

The heat generated in the original weld crystalized and modified the metal on each side of the weld.

Repeated flexing opened up microscopic cracks in the metal adjacent to the weld area, allowing water with other corrosive salts to enter.
Corrosion continues and will eventually cause the area to break off.

Those who have claimed that "rustproofing is NOT needed" should take heed.

From the looks of the photo, this car has had a hard life in an area with the profuse of road salt and other debris with little attention paid to cleaning of the undercarriage.

The only safe and permanent repair is a complete replacement.

Otherwise, the axle will eventually break when placed under stress on the road.

It is an accident waiting to happen.

Repair it NOW or have it break on the road to have it towed in to the shop, hoping you don't have an accident in the process.

 

Regarding the squeak when releasing brakes, that could be at the contact points between the rear brake shoes and their backing plates.

Typically that's 3 points, per shoe, top, middle and bottom. If you can release the shoe's retaining pin clip, then lift the shoe slightly off the backing plate, you can get a dab of anti seize compound into the gaps at contact points.

 

luise83,

Unfortunately, it is THAT dangerous. If it was an airplane, it would be grounded.

The state inspection is NOT comprehensive and is only to check basic systems on the car and rust penetration.

In you case, it is an accident waiting to happen. It is fortunate that it has been found. More often than not, it is found after the part fails,

I don't know how old you are, but your life or the life of anyone you affect is not worth a couple of thousand dollars.

 

If you are aware of any suspension and brake issues, those need to be immediately addressed:

1. Replace the rear axle.

2. Have the rear brake shoes examined. As previously suggested, it could be that a brake shoe is rubbing against the backing plate - the contact points are supposed to be lubricated with high temp grease.

3. The air conditioner compressor might be showing signs of wear. Or a servo motor which opens/closes the vent doors may be having a problem. As long as the AC is still cooling the car, you can ignore that particular problem.

 

Great info Mike. I think I'll be crawling under (my 2005 prius) tomorrow and inspecting that part. I'm very surprised to see a structural part so badly damaged by corrosion.

 

man. they must use an awful lot of salt up there. looks like its been in the ocean. look for a 08-09 axle, or one shipped from the SW.

 

Unfortunately the front end suspension is probably wiped out too. I wouldn't spend a dime on this until I have had the whole undercarriage completely inspected by a decent suspension mechanic. Down here the tire shops have pretty good guys who know the suspensions pretty good
so ask around. Avoid the dealer.

Probably cost about $50 to have it inspected. But at that mileage the car is way past end of life under those conditions. I would imagine the
the cv's and brakes and ball joint/a arm and struts are shot and thats just up front. Thats about $2500 right there.

 

I just crawled under mine to take a few pics. I gave it one quick wipe with a rag and could still see the original black finish intact.





This is a 2004/2005 model (built Dec 2004). It's lived it's whole life less than 1km from the Pacific Ocean.

Wow what a difference salt on the roads must make. It clearly trumps hot humid and being near the ocean when it comes to underbody corrosion!

 

Australia is one of the driest climates in the world. Maybe it's near the ocean, but, like you said, thy don't salt the roads.

Those of you who say that rustproofing is not necessary in some areas be warned.

Either they don't know about corrosion and metals or they are living in ignorant bliss.

Only gold, platinum and palladium does not corrode in the atmosphere.

Aluminum, stainless steel and titanium gets its corrosion resistance from the formation of an atomic level thickness oxide layer.

For steel, the welds and bolted contact boundary layers between mating parts is where rustproofing does the most good.

 

Averaged over the whole continent this is true, much of the interior is very dry. Near the coast however we get fairly good rainfall, particularly on the east coast. Where I'm located we get an average of about 47 inches per year (similar to say New York, and lot more than say San Francisco), and fairly evenly distributed. Not too much further north from here it gets more tropical, with quite a bit more rain and a more pronounced wet season / dry season asymmetry.

Anyway, the lack of rust on mine is certainly not due it being overly dry here. Lack of snow and consequent lack of salt on the roads seems to be the main factor.

 

Where in the world is the OP from? Must use lots and lots of salt on their roads.

That crack would be an immediate safety failure here. I have my annual MOT safety inspection next week and whilst it's always a time of trepidation, I'd rather than that ignore the hidden horrors shown in the ops pic.

To uart. Yes slat on roads really does rust cars - big time. It's also needed to stop you sliding into a ditch on a cold morning. Back in the 70's a car would last about 7 or 8 years before rusting away to nothing. With rust proofing cars will last 20 years or more, though mechanical or safety issues usually get them first. Some JDM cars don't have rust proofing and when brought to the UK they only last a few years before succumbing to tin worm.

Any slight accident damage will often rot away within a few years in countries where road salt it used too.



Be happy you have such a lovely climate

 

yes, salt is needed at times. but in this area, because of all the idiot pansies that work for and because of the federal govt., they use about 10x as much as is needed.
1/2" of wet snow which will melt on its own in a few hours? lets run 3 salt trucks down each road and plow the top layer of asphalt up! and most of those idiot pansies seem to have suvs-- the over-paid ones have bmw x-drives or MB 4matics. but if they see a snow flake = its time to drive 5mph on main roads.

 

Looks pretty bad to me. My point is don't spend to much money to fix this issue hence my dealer avoidance (Markup as you immediately guessed) suggestion.

Btw its very simple to mitigate that rust. Just spray some spray lube periodically on all the suspension components. They make a spray specifically for this application. The suspension will last much longer and no squeaks and rattles.

If and when you get that inspection have them look specifically at the lower ball joints. Failure of those on the road at speed are usually very very painful. I would imagine yours are original.

 

Like what?