the dreaded rust!

:)
morning boys!

THANK YOU for all the great advice i got here.

my friend and i changed my brakes, and he saw a TINY bit of rust in the wheel well. i have always kept this car washed and totally waxed, and undercarriage washes in the winter. Massachusetts.
took it to a GOOD body shop. he found rust starting at the bottom of 3 of the 4 doors.

said it would take 3 days and $400-$500 to fix.

dumb questions
1. should i have him fix it? i am leaning towards yes.
2. how to prevent this rust again?

2008 cadillac DTS. bought new. 54,000 miles, always totally washed and waxed, stored in garage at home and work. daily driver. body looks GREAT.

thanks to all for your great help!

have a great day!
bob

Did you see the rust? Is it starting to perf the doors? Did you look at your warranty to see what kind of perforation coverage you have?

Back in the old days the drains at the bottom of the doors would get clogged (from dust, pollen, dirt, leaves), and the water that comes in around the window seal would back up and rust the door...not so much when they started to use galvanized steel. If you have a mechanic that doesn`t do body work, maybe you can get his opinion on it? He`s got nothing to gain by telling you that you need body work, the way the body shop does.

thank you! rust is superficial. warranty expired. i believe i will fix it. when you lift the rubber gasket on the bottom of the door, you see a thin stripe of rust all along the bottom of the door, in 3 of the 4 doors. i figure to pay $4-500 to make it last 3 years is worth it! car is paid off. mechanically just fine!

thank you! bob

From what you`ve described, I think you`re making the right move. Rockers and door rust can take off in a hurry. Make sure you trust your bodyshop. It`s no secret that proper prep is what makes this job. No sense in throwing money at it only to have rust bubling through come spring.

In my experience the rust n the door bottoms usually start on the inside at the seams. Dirt and moisture collect in the bottom of the door and it rusts from the inside out. No matter how well you maintain the outside the damage is already done. I have countered it on my `06 Gran Cherokee by having it rust proofed every fall with some type of "oily" stuff that drips down inside the seams. So far my doors are totally rust free. I did have to repair the rear lower section of my front fender though this year. Rust popped out where the plastic rocker panel wraps around the metal fender. When taken apart I found a large amount of mud and debris had collected behind the fender and started the dreaded "rot". Get it fixed or it will only spread but I`ve found that once it starts you never totally get rid of it and end up repairing it again down the road. Part of living in the rust belt.

Im with mi Amigo, Gearhead-1 on this too -

As always, have the people tell you first - where is the source of the rust and what are they going to do to remove that source ??

As an example - were the (if they have them), door bottom drain holes plugged up, causing the rust to start inside the bottom of the door panel, and then it went through to the outside, etc.. ?

If its going to go away for good in those places, it has to be removed, cleaned, treated with a chemical rust removal/preventative, then sealed and primed, and repainted...

You live in Mass., so assume they salt the roads in the winter... too bad... that stuff kills more metal than anything.. :(

Good luck with this !
Dan F

thanks guys! great advice!!!!

my plan: treat it now, get it inspected for rust each spring. a friend has a dodge 2002 diesel truck. 300,000 miles. totally rusted out. he bought a truck for $1500 from florida, no rust, will use the body for parts. mechanically, his truck is fine! lots of salt on the roads here!
best,
bob

Bobwax- I`ve dealt with this many times, starting back in the `70s, and as noted it`s hard to do a permanent fix. So hard that I`d expect a (honest) shop to warn you that their repair probably won`t last. I have had this work out OK, both jobs done by Pros and jobs I`ve done myself, but the successes are a small percentage of the attempts and even with the best work and the best products, IME it`s simply a crapshoot.

Hint#1: Some of the newer "paint over rust" products are much better than the old standbys like POR15, and those can make for *great* primers when doing this type of work. Don`t stop at three coats. If topcoating, I`d do it *without* sanding because that sometimes compromises the paint over rust product. Yeah, that can pose problems, but IMO how it looks isn`t as important as keeping it rust-free.

Hint#2: do the same rust remediation/paint-over-rust priming/etc. on the inside of the doors too; get those seams totally sealed up with the stuff.

Hint#3: rustproof the repaired seams from inside the door with something that`ll wick into the entire area in question *without leaving any gaps or pockets*. That last bit is utterly critical and IME determines which products to use for this. If using a pro undercoating gun, I`d use ValuGard`s product, but I have *NOT* done all that well with their aerosol version. Yeah, probably "user error" but I`m not the dullest tool in the shed (note that I learned rustproofing from a very experienced pro and I`m quite meticulous about how I do such stuff) so if it`s not Accumulator-proof then I can`t recommend it. Likewise, my usual fave rustproofing (at least for areas that show), Eastwoods` Black Heavy Duty Anti-Rust, just doesn`t wick well enough for this application IME. (Ditto for the Wurth products I`ve tried.) The aerosol stuff that *has* worked OK for me is Cavity Coater by KBS (who also sell some very good "paint over rust" products and a *GREAT* industrial-type clear). Same ol` same ol`...don`t stop after just a coat or two.

THANK you accumulator! I printed your answer out, will discuss with body shop, dec. 15!

have a super thanksgiving!
bob

the body guy was very honest, and said he cannot guarantee it, but he has been doing this since 1977, and thought it would last 3 years on those spots. OK, so once a year or every 2 years, I pay $400. better than a $400 car payment!

thanks so much
bob

Bobwax- Glad to help, though I`m sorry I couldn`t be more positive about the whole thing.

Note that the issue isn`t so much the need to redo, it`s that eventually you *can`t* redo because you run out of metal and then it`s new panel time.

Oh, forgot to mention, for the "treat the area with acid" step, I`ve found that a product called "Metal Blast" works *much* better than anything I`d tried previously. They all do basically the same thing (dissolve the rust and leave a zinc-based film behind), but for some reason that stuff just outperforms the competition for me...no idea why. The competition always *appeared* to work fine, but I had more problems with recurrance than I have with Metal Blast.

Again, I`ve found that using the right stuff, and those are fairly new products, makes all the diff in the world. As I understand it, the newer (paint over rust and rust preventative) products seal out moisture and air better than older stuff.

Glad you`re trying to keep the car OK, they`re not making DTSes any more and I`ve always liked how they look.