Rock(er) On

[Mike_Windsor]

Well, in the process of getting my 1986 Mercury Grand Marquis LS all fixed up, it was determined this morning that both of my rocker panels are rusted out. Badly.

My mechanic says he is going to fabricate some at his other shop, but he needs the dimensions.

Frankly, I don't even know what a rocker panel is.

Does anyone here happen to know what the dimensions are?

Thanks.

[Mike_Windsor]

I tried looking on Rockauto.com and it didn't know what I was talking about.

I don't blame it, frankly, because when I woke up this morning I wasn't certain what a rocker panel was, either.

[Tiggie]

Rocker panels are the panels that run below the doors. They also make up the lower part of door jambs.

There is an inner and outer part. My inner part has been rusted out for years. Look under the car about midship, at the part of the car body that is just opposite the frame. It's tight in there. The outer is starting to go as well but the aluminum trim under the doors covers all that up nicely.

Rocker panels are a pain to fix right if it's to the point that your mechanic is concerned. I wonder how bad it is? Can you get some pics?

[Mike_Windsor]

Well he showed me as he tapped with a hammer the 31 years of iron oxide that rained down.

He explained that the body would fall apart around me if I didn't get this addressed. Obviously, cars falling apart while being driven isn't "in", so I opted to have this rectified.

No photos, but he said that the tiny drain holes Ford drilled into them was inadequate for water drainage and that contributed to a great deal of it. For what it's worth, he checked the rest of the underside and it's solid; it's just the rocker panels that are shot.

The driver's side aluminum trim started to detach about a year ago.


So he said he'd charge me some $2700-ish to repair the problem. New panels, painted, coated, aligned, etc. Sucks, but it's not one of those "I'll let it go" deals.

[gadget73]

The problem with rotted rockers is that when you start cutting the bad out, you're liable to find that it doesn't end. Somewhere you have to have good metal to weld to, and if there isn't any, basically you replace the car.

[Hearsesrock427]

Yeah the boxes have some problems with the rockers. The outer panels like to rust out thanks to that stupid trim trapping water. I found this out with the '89 after I saw what looked like dirt or mud peeking out from the pass side rocker trim. I was curious so I yanked the trim off, and what I found behind it wasn't mud or dirt- it was a big surface rust scab. Now I was pissed the fuck off at that point so I ripped the driver's side rocker trim off and found some small scabs there too. Thankfully both outer panels were solid, but it would've rotted through in less than a year had I not gotten the rust cleaned up and the metal repainted! Happily sold all that stainless shit for scrap the first chance I got, along with a bunch of other trim pieces that I took off that day. Can't go wrong with less weight and less water traps.

The inner pieces rust out nicely because like your guy said, the drainage was sub-par at best. Which means you have to periodically clean out the rocker drain holes, plus all along the door bottoms and door jambs. You'd be surprised how much water can accumulate around there even from mild showers. If it sits there long enough it'll rust right through the metal. After every rainstorm, get towels and pipecleaners and go to town. Might as well check/clean out fender drain holes while you're there. That's the only way to keep these from rusting from the inside out. It's something to do whilst waiting for the motor to build oil pressure at idle when you first start the car, least that's how I look at it.

Also if the rocker is shot I'm confident at least one of your door bottoms will fail the finger test; these problems tend to go hand in hand. Whatever happens, make sure they don't just do some dinky welds and then cake bondo over it. It's not going to be structurally sound and it won't last for long like that even if you keep the car out of the nasty stuff. My '85 will eventually be getting a new driver's side rocker (it failed the finger test in about 8 different places) so I'll be dealing with that down the road. Do it once, do it right.

[Mike_Windsor]

Well he did inspect the rest of the underside and said everything else is solid, so I am reasonably confident there's still un-compromised metal to weld onto.

We'll see what happens, I guess.

[Hearsesrock427]

It's not like the car was just sitting out in a field for 20 years. (Those are the worst, trust me on that!) I'd be pretty confident with the repair too. Wasn't your '86 rustproofed or something by a previous owner? Would explain why the majority of the car has weathered the salt storm well.

[Mike_Windsor]

I'm so close now, I'm not about to let a potential lack of metal stop me.

[DerekTheGreat]

$2,700 is new car time. If your rockers are toast it's because they rotted from the inside out and there's no way the rest of the car is solid like that guy claims. What's more is even if he puts the new rockers on they will be bare on the inside or at least where he welded and that's where they'll rot out again only at double time. Forget it.

[Mike_Windsor]

Hmm.

[marquisman]

Having bought my current wagon from alberta, I can understand how only odd areas on these cars rust out. Basically because, alberta does not have the typical winter salt problem My wagon is very solid, was never undercoated in it life in alberta and only had some rot behind the rear wheels(where they normally rot, due to holding in damp road dirt). So, with out pictures, its kind of hard to say if its worth fixing or, buy another car. Pics of the rockers, frame rails and floor would be very helpful in giving a final answer.

[Mike_Windsor]

Well, he went underneath the car and examined everywhere for rusting-through - while I stood there and watched - and he pronounced the car as solid, sans rocker panels.

He wouldn't have offered rocker panel replacement as a viable option if it wasn't viable.

Does nobody know what the dimensions for the rocker panels are, by the way?

[sly]

I've never measured them. Most folks I know that have replaced them, pulled them off another car.

[DerekTheGreat]

I'd like to see pics, NFW is it clean everywhere else aside from the rockers. We looked at a Town Car back in early February that looked clean aside from a spot on the driver's side dog leg... Got my flash light out and looked at the frame, rust spots everywhere. Guess that's solid to some people but not me. Don't make me upload a pic of my Townie or Ashley's old one lol. I'd also like to see the area where the front door hinges bolt to the A pillar, that's a common area for rot too.