Being a mechanic in Michigan I am a big fan of rust proofing and under coating. I have seen a lot of good cars that are rusted out on the bottom. I just picked my jeep up two weeks ago and I had mine done. You are going to get a lot of people telling you to do it your self or not at all. I like to have it done by the dealer or zebart. You could do it your self but it would not be as good as having the pros do it. The have tools to get in the door, quarter panels, rocker panels and all the other places you can't get to. Plus most of them will warranty there work against rust and will pay to repair it if yo do get rust. The way I look at it is its a lot cheaper to have it undercoated than to have to pay a body shop to replace the floor panes or rocker panels. The bottom line is is your jeep, your money. Only you can make the call

 

I "undercoat/rustproof" my vehicles with Amsoil HDMP and they still look new several winters later. A single can will easily cover everything under a JK or JKU. It sprays on like WD-40 and when dry, leaves a very thin wax-like finish that repels water and so far has held up to dozens upon dozens of underbody flushes.

How I apply it is simply spray it on and then hand-wipe it because it has a slight orange tint if you spray it too much in one spot. One thing it doesn't do is plug up any drainage holes. Something else the HDMP does is stop rust after it's formed; it just penetrates any rusty areas (i.e. ball joint areas, steering knuckles, trailer hitch receiver, nuts&bolts) and darkens them. The hitch on my Grand Cherokee still looks like new 2yrs later after a few salty Chicago winters. I've only had my JK this first winter, but a friends JKUR treated the same way with HDMP still looks almost like new underneath.

If there's a con to using the HDMP, all I can find so far is that the film it leaves has a bit of tackiness to it after it dries which can pick up dust to make gloss black frame paint look a lot less glossy. So, while my silver JK's black frame is protected and stays black, it is a dull black rather than shiny new, if you know what I mean. When I wash either of my Jeeps, the water beads off the treated undercarriage like water beading off a freshly waxed hood. Highly recommended, and it's cheap too.

 

In my area it would be a waste. In yours, maybe not. I can see the benefit where there is a ton of road salt. If I was up there and decided to do it the dealer would be the last place. If Zeibart or an equivalent does it then that's what I would use if I wasn't going to do it myself. Dealers, if they have a company come in and do it, will make a profit and pass the cost to you which is fine if there is no other choice.

 

Being a mechanic in Michigan I am a big fan of rust proofing and under coating. I have seen a lot of good cars that are rusted out on the bottom. I just picked my jeep up two weeks ago and I had mine done. You are going to get a lot of people telling you to do it your self or not at all. I like to have it done by the dealer or zebart. You could do it your self but it would not be as good as having the pros do it. The have tools to get in the door, quarter panels, rocker panels and all the other places you can't get to. Plus most of them will warranty there work against rust and will pay to repair it if yo do get rust. The way I look at it is its a lot cheaper to have it undercoated than to have to pay a body shop to replace the floor panes or rocker panels. The bottom line is is your jeep, your money. Only you can make the call

Being a Michiganian as well, i need to get this done. where did you get yours done at? This salt does very bad things.

 

I had my excursion done at zebart and had my jeep done by the dealer were I bought the jeep. I am happy with both.

 

Every time a dealer offers the undercoat option I don't go for it. Simply because I'm a cheap bastard. I've never had any problems (I live on the east coast) with rust and from what I understand, most new vehicles are pretty well protected from the elements.

 

Bet ya that your dealer is advising against it because they don't offer it in their list of junk they try to sell you after striking the deal. The total price for all the add ons I was offered was like $14k! Obviously declined everything but wtf.

If you want it get it, can't hurt.

 

Any difference between the two?

 

The zebart stuff is black. For the warranty you have to take it back to them once a year to have it touched up or they will not cover rust repair. The mopar one you don't have to have to take it back. The mopar product is more of a tan color.

 

Maybe crawl under there with a hose more often so the
road salts don't work through to the steel??

 

I used Ziebart for about 20 years, but quit on it a Toyota Forerunner and two Isuzu Troopers ago. Applied when brand new but in 8-10 years, the undercoating would dry out, become brittle, and start to separate from the underbody. Salt, moisture, dirt was trapped and started to accelerate the corrosion. The annual inspections would spot cover up the aging/failing undercoat. This is not the answer if you want to preserve your Jeep indefinitely.

 

Also a Michigander. When my ordered 2015 JKU arrived, I had the dealership take it to a local company that specializes in undercoating, detailing, etc. I also spray the undercarriage with Fluid Film each Autumn. Seems to be holding up well, and was not really an impediment when doing upgrades.

 

This question is from 2013. OP's last post was in 2017. I don't think he cares anymore.

 

I recommend watching Eric O's demonstration on how rubberized undercoating destroys cars by capturing moisture and accelerating rust.

 

has anyone used bed liner (x-line) on their frame? considering this over undercoating. Of course the guy at x-line is like yea.. great idea...

 

I think its a horrible idea. how would you ever work on it. just fluid film the thing every so often...cheap and easy....and it works.

ps yes I realize the original was a long time ago

 

Having lived for years where they really salt the roads (Massachusetts) I have to give a thumbs down on undercoating if the purpose is to prevent rust. The best advice I can give here is to get one of those hose attachments (or better the one for a pressure washer) for washing the underside of your vehicle and use it regularly. We had two vehicles, one with and without undercoating. My truck became rust eaten because the rust would travel under the undercoating because it is impossible to cover everything. This vehicle was done by professionals and was their "top of the line" translation "most expensive" offer. Both vehicles went through the car was and got the deluxe under-wash regularly. In between I used a wash-broom to clean the salt from the underside. The car wasn't affected by rust.

This was pretty much mirrored in what I saw in the vehicles of my co-workers.