I recently bought a 2000 coupe from upstate New York and previous to that it was in Chicago. It had 17,000 miles on it when I bought it.

For the first time, my shop put it on a lift to install a tunnel plate and some other items. The entire underneath of the car had a white powderery coating and some metal lines had rust on them. The mechanic was concerned about under the battery area and is going to pull the computer and clean it up and remove any white powder, if there is any; he said it is important to do. They also recommended to power wash the underneath of the car. I've never used this shop ( J & M Corvette ) and I hope they are straight up in what they tell me/do. I will give them the benefit of the doubt.

The exterior of the car is spotless and underneath it was not. It looks like it was driven in snow and salty weather.

Am I to be concerned about this corrosive looking underbelly ? Are the underneath of these cars normally clean or normally corrosive looking ?

Any comments will be appreciated.

777

 

I would doubt that a 2000 with only 17,000 saw much (if any) winter driving - it has to have been a garage queen. The original batteries in 2000s were known to leak, so I am wondering if this is the cause of the powder.

 

Im sure a leaking battery wouldn't cause corossion to the entire underbody of the car. I wouldn't be suprised if Chicago dumps butt loads of salt though. It only takes one trip in a wet salty road to cover a car.

 

I live in upstate NY. If that car was driven in the winter at all, the undercarriage is salted. Heck, this may sound crazy, but lick your finger, touch the white powder and taste it... betcha it tastes like salt (have a big glass of water handy to rinse and spit out afterwards).

They dump TONS of it up here. My C5 is hides in a garage from the first snowfall untill the sring rain finally rinses that corrosive crap off the streets. The newer "green salt" is even clingier (it looks green on the truck but the white crust on your car is tougher to rinse off).

Wash the undercarriage completely. Flush the water through the spaces between the door opening and fenders, hood cowl, etc... If possible find the drain holes in the frame, and back flush with water.

I have lived in CNY my entire life. Salt finds its way into spots you would think were impossible to get to... and given time, it will create its own drain holes! .

Chuck

 

Salt you can almost bet, I don't know if I would taste it though

 

My last Corvette I had driven in Chicago in the winters when there (I thought) was no salt around. The frame ended up rusting out so to me an ounce of prevention is worth the problems it could cause you down the road.

 

Along these lines, when you pull the panal and expose the ECU, is it normal, due to age, for it to be covered by white powder or is that condition the result of battery acid leakage ?

Is white powder the kiss of death for the ECU and harness or is it of no concern ?

777

 

Alot of people think because the body of a Corvette is not metallic, it means their cars won't corrode. That couldn't be further from the truth. The frame is made of steel, suspension components, engine components, exhaust system, all are made of materials that can corrode and electrical grounds are very easily corroded, even if your vette hardly sees bad weather. I'm not saying you should never drive in the rain because that's just silly but things like winter salt on the ground can hurt your vette or any vehicle, long term.

 

Another reason why I left Rochester. Not much (if any) salt here in Nashville.

 

I used to live in Chicago. TONS of salt on the roads.

 

What comes after winter?
Spring!!

What comes with spring?
April showers!

Drive your car all year long like me and Shermon. April showers work wonders in washing away the winter salt.

Charlie

 

Also avoid yellow snow.

 

Salt hasn't hurt my car at all. It's been driven every single winter.

Life is too short to worry about silly things such as this.

 

The owner's manual says:

Underbody Maintenance
Chemicals used for ice and snow removal and dust control
can collect on the underbody. If these are not removed,
accelerated corrosion (rust) can occur on the underbody
parts such as fuel lines, frame, floor pan and exhaust
system even though they have corrosion protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this for you.
---------------------------------------

A lot of the C5 underbody is aluminum (including suspension), it's really good looking and functional. Although older corvettes had some serious rusting problems, I think the C5 is much better. None the less, I do ocassionally hose off the bottom of my car. I have used underbody drive threw (brushless and trackless) car washes and drove up on ramps using a hose.

 

I'd have to agree that it sounds like salt on the underside. Just clean it up as best you can and avoid driving on salty roads as best you can.

 

I flushed the underbody last night! Yup, got caught in, and drove in, a huge downpour. The underbody is now cleaned of any accumulated salt from the winter and I'm good to go until the next snow and salt season.

Charlie

 

driving through a good rainstorm or two is a good way to remove any salt.

 

Drive it in the rain. That will clean the salt off

 

If the battery tray and metal below it is rusty or severely corroded, then there was a probably a battery leakage issue. Pull the battery and the battery platform. Get a can of CRC Battery cleaner and spray all of the affected area. Wash down with soap and water. Thuroughly dry. Look for any 'heavy' corrosion damage. Sand any rough corroded surfaces smooth. Primer the affected areas. repaint with Black semi gloss chassis paint or (I used) semigloss engine enamel. Check your HVAC system operation. Make sure all selection modes for air flow work. If they don't or only one mode (all vents) works, you probably have a vacumn system leak. The hoses run under the battery and may have been damaged by the original leaking battery acid. Search the forum for repair hints. Not uncommon a problem. If you're really concerned about the white powder stains, then I'd get the car on a lift and check underneath for any rust spots and address them also with TLC and some fresh paint. Use a strong cleaner like Simple green and scrub as much of the corossion powder of as you can using a scotch pad you use in your kitchen for Teflon pots/pans. If used lightly, it won't remove the under chassis paint, just the corrosion. If that doesn't work, then, after cleaning, paint the affected area. Good luck.