Underbody Rust

[hookedon4wding Advanced Member Find all posts View Profile Close hookedon4wding]

I was under the car the other day checking out the diff breather locations and noticed the exhaust and muffler have surface rust all over them. Is this normal? Never had any on the exhaust of the Pajero.

Cheers, Sam.

[dannyson Member Find all posts View Profile Close dannyson]

Re: Surface Rust on Exhaust

Had a look at mine the other day ..... 10 month old 150 ... UK - LC4 (VX In Aust.) - covered in rust :shock: - my 7 year old 120 had NONE ........ whats that all about .......... :?

[dannyson Member Find all posts View Profile Close dannyson]

Re: Surface Rust on Exhaust

Nobody else got it? ... :shock:

[dannyson Member Find all posts View Profile Close dannyson]

Re: Surface Rust on Exhaust

For goodness sake :shock: ... can nobody go out and look at theirs to give me some peace of mind that its just not me!!? :shock:

[Bert Junior Member Find all posts View Profile Close Bert]

Re: Surface Rust on Exhaust

mine had surface rust at where it joins with the muffler to the tail pipe. the muffler had rust on the underside and pit marks. looking further up found rust at the exhaust manifold. i had just had it checked out by Toyota at the 1000km "service" this morning and they told me this is "normal" ! ?? and that the pit marks are weld points in the muffler. ?? i have owned quite a few cars but this is the first time i've seen rust on the exhaust. anyway they said they polish off the rust. i will check it in a weeks time and post what i find. just a few weeks old and the exhaust starts rusting- what are they using? mild steel? btw, i don't live near the seaside.

[BNEGXL Member Find all posts View Profile Close BNEGXL]

Re: Surface Rust on Exhaust

2010 D4D, original Toyota stainless system, 4,000 k's, not a spot of rust,

[Bert Junior Member Find all posts View Profile Close Bert]

Re: Surface Rust on Exhaust

Good day BNEGXL,

what's the cost to have it changed to S S ?

[hookedon4wding Advanced Member Find all posts View Profile Close hookedon4wding]

Re: Surface Rust on Exhaust

Well I had the bash plates off over the weekend to put a new TJM Underguard on and there is also rust on some of the other components as well.

Does anybody know what the Toyota corrosion warranty covers? The car is due for it's first (10,000km) service in a few weeks and I need to know the situation before confronting the dealer.

Surely it can't be normal to be rusting already :? . I have had it on the beach for a very small amount of time (nowhere near the water) but I was vigilant in spraying the under body and the rest of the car with a high pressure hose as soon as possible afterwards.

Cheers, Sam.

[hookedon4wding Advanced Member Find all posts View Profile Close hookedon4wding]

Re: Surface Rust on Exhaust

Ok, to add some spice to this thread, here're some photos of the rust under my 9,000km old Prado.

I would've thought this isn't good???









Cheers, Sam.

[BNEGXL Member Find all posts View Profile Close BNEGXL]

Re: Surface Rust on Exhaust

Bert,

You've got me wondering now, I was told by an aftermarket exhaust supplier that standard D4D exhaust is stainless, I had a look before replying to this thread, it certainly looks like Stainless, so this morning I tried to stick a magnet to it, it sticks!

So either it's not stainless or it's poor quality stainless.

I then tried the magnet on our Falcon exhaust, it's suposed to be stainless too, magnet sticks again.

Maybe exhaust stainless steel is a lower grade? Maybe the exhausts aren't stainless? Buggered if I know.

Anyway, our D4D exhaust is unmarked and as new with almost 4,000 k's on it.

Our 2005 V6 120 exhaust was covered in surface rust from the cat back almost from new and stayed that way until we sold it a month ago with 90,000 k's on it. The manifolds were rust free.

[Bert Junior Member Find all posts View Profile Close Bert]

Re: Surface Rust on Exhaust

the pics from Sam is getting me worried. i wonder when shipping, it encountered sea spray or when loading/unloading? which means the batch is affected. or is the manufacturing plant near seaside. Fiat cars had that problem years ago.

what can we do about it? collectively check our exhaust, post results then launch a complain to Toyota?

or do we fix it ourselves? does anyone know of any high temp antirust paint? if memory serves me right, there was a light blue colored exhaust manifold paint used on the toyota Supra 1970's model. point is, the paint does exist. anyone know where we can get it? i'm going this way as i was disappointed with the toyota service (1000km inspection and answer any query). they were quick to palm me off. i had a few points listed and only 2 were addressed. 1 was to have the remotes programmed to open and close windows. this was good. 2. half addressed. there was rust on 2 areas of the exhaust (so far as i can see) surface rust at the manifold and the joint bet. muffler and tail pipe. they polish the rust off at the joint and left the manifold one for me to clean off.
what a feeling.

Bert

[Riv39 Advanced Member Find all posts View Profile Close Riv39]

Re: Surface Rust on Exhaust

Wow those pics look bad after so few km's, surely salt water must be involved? My D4D has no rust on the exhaust or anywhere else for that matter after approx 7600km (April 2010 delivery). Plenty of grease on the exhaust from the slip joint, maybe that helps :shock: however that is another story altogether.

[Photographer Lurker Find all posts View Profile Close Photographer]

Re: Surface Rust on Exhaust

....So either it's not stainless or it's poor quality stainless.

I then tried the magnet on our Falcon exhaust, it's suposed to be stainless too, magnet sticks again.

Maybe exhaust stainless steel is a lower grade? Maybe the exhausts aren't stainless? Buggered if I know.

In my past life (1971-1999) I was an exhaust system specialist so I guess I would be qualified to answer this question.

There are basically three grades of stainless steel commonly used in the manufacture of motor vehicle exhaust systems.

302 and/or 304 grade (non magnetic) is used to make the muffler internals, end plates and barrels, it is a lower grade than 316 used to make things such as kitchen sinks.

The problem arises with the pipework where a lower grade again, 409 (magnetic) material is normally used, it has a lower % of chromium and rapidly discolours to a dirty brown finish which may look like rust. The reason 409 grade is used for the pipework is that it is much easier to bend so it gives a more reliable bend without collapse with less wear on the tooling.

[hookedon4wding Advanced Member Find all posts View Profile Close hookedon4wding]

Re: Surface Rust on Exhaust

Wow those pics look bad after so few km's, surely salt water must be involved? My D4D has no rust on the exhaust or anywhere else for that matter after approx 7600km (April 2010 delivery). Plenty of grease on the exhaust from the slip joint, maybe that helps :shock: however that is another story altogether.

Never been in salt water. Only time it's been near the stuff was on our Eyre Peninsula trip where we did less than an hours driving (in total for the trip) on the sand. The underbody was thoroughly pressure washed within a day or so after any sand driving.

I am going to forward the photos to the service manager and see what he says.

Cheers, Sam.

[Riv39 Advanced Member Find all posts View Profile Close Riv39]

Re: Surface Rust on Exhaust

Maybe the D4D has a differnent grade of SS on the exhaust.....it doesn't explain the other areas though.