I just got a G35x 2004, very clean car with the exception of underneath, where there is a fair amount of rust on some components.

Is this very unusual?

Can I just replace the components that have rusted?

Any suggestions?

I guess the thing that worries me the most is the oil pan

I am confident your exhaust has a leak, and a pretty bad one.

The other parts are really rusty - I have never seen anything so bad on a G35 until today. Where is your under cover panel that goes under the engine area?

That other component in the 2nd image looks pretty bad as well.

Where do you live? I am in Canada - and have nothing like this on my car. (Roads are heavily salted in the winter, my car is driven through each winter)

Oil spray / undercoating will not help you now. Looks like the last owner did not do those things previously.

Thanks for the response.

Michigan.

I guess I went against my better judgement on this one as the rest of the car was so clean.

I will do what I can to clean it up and look at replacing the exhaust.

I am sure the car is fine overall. Post pics of the entire car.

I would recommend a really good underwash, and then after completly dry - oil spray. I don't think this will stop further rust from occuring, as once started - I don't know if it can be stopped, but I am sure it can be slowed down.

A muffler shop will be able to take care of that leak for you for a low cost, or you can replace the complete system.

Have a mechanic, or anyone check out that rusty part in the 2nd image, so see if it is as bad as it looks.

yeah, this is more rusty than what one would expect. this car was driven in the snow, with salt on the roads. i would fix the exhaust, or just replace it with a used exhaust - look at your local car classifieds. as far as oil pan goes, that can be removed, cleaned and repainted - or outright replaced with a used part - but that's a fairly big job, and i wouldn't attempt to do it myself as a DYI.

Was this car garaged? Almost looks like it where it is run on roads with salt, etc. on it and then placed into a much warmer garage and thawed out.

I think it must have been garaged - the interior and exterior are almost perfect - with the major exception of the stuff underneath.

I will post pics when I get home from work.

There is a mechanic that I trust, I am going to take this to him this week.

If I do the exhaust should I go OEM or 3rd party?

Any suggestions if I am not looking for louder?

If you go OEM, shop for the following:

Coupe Midpipe
HR Y Pipe
Reuse the old muffler, or if bad shop the forums.

Note: I had a Stillen Stage II and hated the drone, and loudness - but the HP / Torque increase was noticable. I would strongly suggest you stay away from that, unless that is specifically what you are after (noise = torque / hp)

I went with the coupe midpipe and HR Y Pipe and am very happy as it is better then the stock sedan sound with minimal drone. Don't care much about the loss in HP/Torque compared to the Stillen Stage II, as I don't race the car - nor will 20-30hp really make a difference in the real 'commuting' world.

I would also recommend a coupe intake, and a plenum spacer - all low cost upgrades.

Thank you.

This is really helpful.

I will start with these replacements / upgrades and hopefully I can get the other rust spots under control.

Good luck!

I don't think this will stop further rust from occuring, as once started but I am sure it can be slowed down by oil spray or you can replace the complete system.