Roof and Body

I have a 2004 PC 2350 (Ford E350 w/V10) we love, have had it now about four years.  We have never had the roof sealed, and I notice that the coach body is oxidizing quite a bit and leaving white streaks down the sides, and on the cab windows.  Up until this last winter it was parked uncovered, but this winter we put up one of those flimsy carport things that's working quite well.

First the roof:

I am a bit unsure as to what to use to seal it.  All the seals around vents, etc. are cracking. 

Dealer wants almost $300 to seal it; is that a decent price?  If I decide to seal it myself, what product is recommended?  I don't want to get the wrong stuff and have separation problems.

Then the body:

What to y'all recommend for the coach body for cleaning and sealing and polishing it to look as best as it can?  It's lost its gloss and the graphics are starting to peel on the edges. 

Thanks for any advice!

I had a 2005 with the same issue. I first removed all the top front cab decals with a heat gun and scraper.  I found that I liked the new look so I didn't replace the graphics. It took me three days to get rid of the oxidation, seal, wax and then polish the unit. I did it all with a electric buffer. And then another 2 days to tape and repaint the bottom.

So if they are going to get rid of oxidation and polish/wax the entire unit $300 sounds like a great deal.

Here is a picture of the finished unit.  I also installed all new LED marker lights, new window gaskets and repainted the mirrors.

Hi CABass,

We owned our first motorhome for 24 years.  It had a seamless fiberglass body like the Coach House and Chinook brands.  CLICK HERE to see many pictures of our old rig.

Exactly as you describe with your PC, that first rig of ours did the same thing.  I found it very hard to keep it looking nice and we had it garaged for all but the first 5 years.  Like zolman says, the best way to restore the finish is through a restoration process.  This is what I recommend for best results with least effort.

Buy a rotary/spinning polisher like THIS ONE.....not a random orbital one.
Buy THIS EXACT ultra cut compound.
If you want it to look even better, do it a second time with a more mild abrasive compound like THIS ONE.
Once all good and shining again, I would use a product like NuFinish

When ordering our new PC back in 2007, I went with the full body paint job "specifically" to avoid dealing with the same issues.  If ordering a brand new PC with plans to leave it outside in the elements, I highly recommend an ALL WHITE full body paint job, painting only the house portion to match the original Ford cab portion.  The white paint will hold up extremely well to the sun and will also keep your PC interior cooler than dark colors.  The white paint will protect all your plastics from UV damage & yellowing.  I imagine the cost of doing so would also be quite affordable.  I don't know about painting a 2004 all white in the year 2021, but if I owned one with your situation, I would do some research on the cost and preparation for painting.  If we did not have a garage for our old and current motorhomes, I would have considered getting them painted all white.

For reference on my recommendation for restoration with the rotary polisher and heavy cut compound, last year I bought a 2007 Saturn Sky that required a mild restoration.  The paint was weathered up but could be rescued.  I started with this.


This is after using just the first step with the rotary polisher and heavy cut compound.  It left fine swirl marks which you don't see here.  On a white gel-coat fiberglass body, I don't think you will notice any.


Using THIS random orbital buffer and the second mild compound, I got it to where I wanted to get to.


CLICK HERE to see many pictures of the end results.

I'm not sure what do do about the roof itself.  Regarding the sealants - Use lapseal to reseal at the vents, frig exhausts, etc.  This will flow out on the flat surfaces and look like what is there now (sort of.....).  You need to first clean the old sealant very good so this will stick, or remove it but that would be a big job.  For all the other joints - roof to sides, roof to rear cap, roof to front cap, vertical seams on sides, horizontal seams behind there cab doors, etc, use the ProFlex product.  For this, clean joint very good, tape both sides of joint, apply, smooth out with soapy finger, remove tape.  Looks better than new....

If they are charging $300 to clean and reseal all the vents, ac as well as the entire seam around roof to the sides and top cap that’s a bargain.  Oh you can do it yourself and save money but from a labor standpoint it’s a great deal IMO.

Clean everything with a brush first, then again with mineral spirits before applying the Dicor self leveling lap sealant. I would not remove or disturb  the original sealant around the rooftop components unless replacing a part or investigating a leak.  Inspect all the plastic vents for  deterioration too. On mine the bathroom vent lid and holding tank vents were brittle and ready to crumble. Personally, I would apply the Dicor myself and spend $300 to hire a detailer, then apply a uv inhibitor polish wax or sealant every 6 months so it won’t oxidize again.  Like Ron  said, it’s going to be a 2 step process at minimum to attack the oxidization with compound then apply a polish wax.

I'm not sure what do do about the roof itself.  Regarding the sealants - Use lapseal to reseal at the vents, frig exhausts, etc.  This will flow out on the flat surfaces and look like what is there now (sort of.....).  You need to first clean the old sealant very good so this will stick, or remove it but that would be a big job.  For all the other joints - roof to sides, roof to rear cap, roof to front cap, vertical seams on sides, horizontal seams behind there cab doors, etc, use the ProFlex product.  For this, clean joint very good, tape both sides of joint, apply, smooth out with soapy finger, remove tape.  Looks better than new....

Dicor also makes a non-leveling sealant.

You MUST clean all surfaces where the sealant will flow until they look brand new with no dirt even in the cracks.

$300 is a good bargain to have a shop do it.

I just paid $600 to have a shop cleanup the fiberglass (on my 2551) and it looks great, nothing will cleanup the decal stripes.

I too feel $300 is a bargain.

Dicor is  ~ $10 per tube.  The self leveling stuff is a bit runny, but If  you use too much on the roof no one will ever see it, unless it’s at a proper  car show where they won’t judge it if you leave the  hood closed.  I will probably use too much Dicor  when installing the King Jack antenna and solar panel array, but it won’t leak.

If your going to apply self leveling roof sealant do it on a warm day in the sun. I've made the mistake of doing it in a garage on a cool day and the sealant didn't spread level.

And I only use Dicor. I've used other brands of sealants and they quickly picked up a "dirty" look that even acetone could not remove. Dicor didn't do that at all.

I had a 2005 with the same issue. I first removed all the top front cab decals with a heat gun and scraper.  I found that I liked the new look so I didn't replace the graphics. It took me three days to get rid of the oxidation, seal, wax and then polish the unit. I did it all with a electric buffer. And then another 2 days to tape and repaint the bottom.

So if they are going to get rid of oxidation and polish/wax the entire unit $300 sounds like a great deal.

Here is a picture of the finished unit.  I also installed all new LED marker lights, new window gaskets and repainted the mirrors.

Beautiful rig!   That $300 is only for sealing the roof - the rest of the stuff they don't even do at the dealership I purchased it from.  I know of one place in town here that details RVs and they charge by the foot -- but I don't recall how much per foot at the moment.  They do an excellent job from what I've seen, usually big beautiful diesel pushers.

Exactly as you describe with your PC, that first rig of ours did the same thing.  I found it very hard to keep it looking nice and we had it garaged for all but the first 5 years.  Like zolman says, the best way to restore the finish is through a restoration process.  This is what I recommend for best results with least effort.

Buy a rotary/spinning polisher like THIS ONE.....not a random orbital one.
Buy THIS EXACT ultra cut compound.
If you want it to look even better, do it a second time with a more mild abrasive compound like THIS ONE.
Once all good and shining again, I would use a product like NuFinish

When ordering our new PC back in 2007, I went with the full body paint job "specifically" to avoid dealing with the same issues.  If ordering a brand new PC with plans to leave it outside in the elements, I highly recommend an ALL WHITE full body paint job, painting only the house portion to match the original Ford cab portion.  The white paint will hold up extremely well to the sun and will also keep your PC interior cooler than dark colors.  The white paint will protect all your plastics from UV damage & yellowing.  I imagine the cost of doing so would also be quite affordable.  I don't know about painting a 2004 all white in the year 2021, but if I owned one with your situation, I would do some research on the cost and preparation for painting.  If we did not have a garage for our old and current motorhomes, I would have considered getting them painted all white.

Thank you, Ron, for the exact advice!  Very good description and recommendations and it looks like an excellent job.  I also prefer basic white - all the swirling graphics on modern RVs does nothing for me and I'd rather be a little less conspicuous (but at the same time, the most important thing to me is how it runs and drives and camps, etc.).  But I HATE having a dirty, oxidized rig.

I'll give your tips a try!

I'm not sure what do do about the roof itself.  Regarding the sealants - Use lapseal to reseal at the vents, frig exhausts, etc.  This will flow out on the flat surfaces and look like what is there now (sort of.....).  You need to first clean the old sealant very good so this will stick, or remove it but that would be a big job.  For all the other joints - roof to sides, roof to rear cap, roof to front cap, vertical seams on sides, horizontal seams behind there cab doors, etc, use the ProFlex product.  For this, clean joint very good, tape both sides of joint, apply, smooth out with soapy finger, remove tape.  Looks better than new....

Thank  you , WillLloyd!  I appreciate it!  I know that there is some reason to be careful about which sealants to use with the fiberglass roof.  I watched a YouTube video by a guy who used FlexSeal in gallon cans and squeegied the stuff all over the roof and it came out great - a year later it was still looking like new and didn't have any holes or cracks in it.  It looked amazing ... but I'd sure hate to use the wrong stuff and have seal separation issues.

Clean everything with a brush first, then again with mineral spirits before applying the Dicor self leveling lap sealant. I would not remove or disturb  the original sealant around the rooftop components unless replacing a part or investigating a leak.  Inspect all the plastic vents for  deterioration too. On mine the bathroom vent lid and holding tank vents were brittle and ready to crumble. Personally, I would apply the Dicor myself and spend $300 to hire a detailer, then apply a uv inhibitor polish wax or sealant every 6 months so it won’t oxidize again.  Like Ron  said, it’s going to be a 2 step process at minimum to attack the oxidization with compound then apply a polish wax.

Thanks, CalCruiser!

If your going to apply self leveling roof sealant do it on a warm day in the sun. I've made the mistake of doing it in a garage on a cool day and the sealant didn't spread level.

And I only use Dicor. I've used other brands of sealants and they quickly picked up a "dirty" look that even acetone could not remove. Dicor didn't do that at all.

I wondered about that.  I only use Dicor and it looks like crap it’s so black with dirt sticking to it. I had hoped maybe another brand would be better. I think it comes down to heat. If you live or ever use your rig where it gets hot expect it to look like crap if there’s ever a dusty day when the temps are over 100.  So based on your findings Dicor holds up better than the others under high heat.  I wonder if there’s any that do better than dicor.

And your right even acetone won’t help once the dirt sets in.