Undercoating before winter?

[truck69]

My 69 Chevy will be put away for the winter in a month or so and it will be put in a unheated but dry pole barn. The body is pretty good with no spots with rust coming thru. My question is should I get it undercoated before winter or just wait til next year? Or is it worth the money? It wont see a snow flake and wont be taken back out until all the snows gone. Any help would be great.

Thanks. Truck69

[Joe67]

Don't undercoat. Waste of money IMO.
I used to apply it at at shop in the Eighties. All it does is seal up the factory drain holes etc as well as make a mess.

Especially on a nice classic vehicle you plan to store indoors during the inclement weather. I would keep the vehicle off of the ground and try not to store it on grass/dirt if at all possible

[Dean]

Another thing to consider is rustproofing it. I bought the spray run for about $100 and the actual liquid cost about $25.00/gallon. It sprays a sticky clear liquid anywhere you want. Gun comes with nozzles to get in all the hard to reach areas. You have to do something around here in the salt belt or you will have swiss cheese cars.......lol

The stuff works as none of my daily driver vehicles has so much as a rust spot. And all of them are old vehicles now.

[cdowns]

spraying undercoatin on an old vehicle is a waste of money unless you get it down to bare metal and prime it first, all you do is cover the rust and give it an ideal place to grow

[truck69]

Thankyou for the info. I have a question. What is the difference between undercoating and rust proofing?

Thanks. Truck69.

[Smokin72on20s]

rust can still grow eventhough you have sprayed coating over it? does it have to be bad rust? what about just some surface rust? i plan on spraying underneath my bed with some 3M undercoating that i bought for my wheel wells, i do plan on sanding the surface rust and priming it, or should i just leave it alone?

[Alex Hayley]

truck69, I have used neither on any vehicle I have owned. I was always under the impression undercoating was a sounddeadener and rust proofing did exactly as the name implies.

[curbyk]

As I recall from my growing up days in the north, undercoating is usually the same product sprayed on accessible surfaces under the vehicle, while rust proofing includes spraying in doors, rocker panels and other rust prone areas, I know in the olden days they sometimes had to drill holes to get access to some areas and used plastic plugs to seal them

[cheyenne10]

Many new car dealers try to put hardsell on dealer installed undercoating. It was recently told to me to help prevent rust. Fact is factory installs some undercoating and rust proofing procedures at the factory. Dealer installed stuff is not worth it IMHO. I had a dealer loose a sale on a $38K car earlier this yr. It got down to they installed this process for $695 on all cars sold by them. It was an out of town dealer and local dealer was willing to sell me exact car for $700 less. Yes same car (vin etc) as they trade stock all the time. I ended up saving an additional $1800 with new incentives from even another local dealer in end on matching equiped truck.

Bottom line is the manufacturers don't want them to last forever. They ARE in the parts and service business too. Its very often been told to me that there is MUCH more profit in parts and service after the sale.

I am going to add the 3M undercaoting to dads 72 in fender wells to start and maybe more. Bought a case (6 ca ns)of the unpaintable version for just over $20. I will post pics when done.

[Dean]

Undercoating and rustproofing is not the same thing. My gun will spray either stuff but they are different. Rustproofing is almost like a waxy greasy looking stuff while the undercoating is a back tar looking stuff. I personally like the rustproofing much better being in the rust belt. It sure beats what we used to do which was oiling the whole car. That worked too but you had to do it every year and the car dripped for quite awhile.