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Old 05-01-2018, 05:31 PM   #1
Join Date: Apr 2018
Posts: 64
Bed size

Just bought a 2018 Cougar 367FLS fifth wheel over the weekend. The mattress don’t look like much. My wife would like a memory foam mattress. We were told it is a king mattress. Mattress tag says 70x74. King mattresses that I have looked at are 76x80. Anybody tell me what size mattress will work and a website to find? Thanks

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Old 05-02-2018, 07:02 AM   #2
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We have the same model. We bought a king size memory foam topper at Costco and cut it down to size

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Old 05-02-2018, 12:57 PM   #3
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Congratulations are in order for your new Cougar purchase!

We waited way too long to make the change-over to a "real" mattress... fighting sheets that did not fit etc etc.

Do yourself a favor and do what we did and get a true mattress. We purchased a Queen size from IKEA (for platform beds). Best upgrade ever.

I cut down the OSB board platform to the actual Queen size mattress. Now you can purchase sheets that are to your liking & fit! You will also have the luxury of about 5 inches extra on each side of the bed area!
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Old 05-02-2018, 02:23 PM   #4
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You have to be careful about the size. If you buy something new that's longer than the length of the king bed that's already in there, you could have an issue with the slide closing. For example, I used to have a Keystone Retreat destination trailer. The king bed was on a slide-out, and I purchased a longer length mattress than what was originally there. As it turned out, the slide couldn't fully retract because the mattress was too long and it hit the dresser at the foot of the bed. All that I'm saying is to take things like this into consideration prior to buying something new.
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Old 05-02-2018, 03:58 PM   #5
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Bed size

We have been very pleased with our king size 4” gel/pillow-top memory foam topper. If you decide to go that route we found the neatest trick for cutting to size! We traced the original TT mattress size on to the foam. Then we used an electric kitchen knife to do the cutting (picked this up from a YouTube video like the one linked below). It cut the foam like a hot knife on butter and the topper fit the mattress perfectly.

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Old 05-04-2018, 04:35 AM   #6
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Will a 'standard' king fit the space? Can that space be altered somewhat to fit a 'standard' king by adding extensions? I have seen a few instances where RV owners have installed a drop down extension to the actual bed platform length to accommodate a 'standard' mattress. I have not seen any side extensions but a 3"/side extensions may work in the allowed space.

Unfortunately RV builders seem to think that there 'special size' fits all. It doesn't if you are over 6' tall which many Americans are these days
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Old 05-04-2018, 06:05 AM   #7
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I put an Ikea King in mine. I cut new OSB for it. The head of it has to 'squeeze about 1x3/4 inches to fit. Being memory foam its not an issue. The length was fine. It goes to about 1" from the dresser at the bottom. I can take a picture of it if you want. It was amazing what a difference that 6" of width makes. Add that to being able to use sheets you can find anywhere makes it totally worth it.
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Old 05-04-2018, 06:40 PM   #8
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Congrats on the new trailer. We upgraded our mattress after about the 4th night. I told DW I was not going to spend one more night on it. Now we sleep better in the 5er than we do at home. We ordered ours to fit, a standard size would not allowed the half bath door to open all the way.

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Old 05-05-2018, 11:54 AM   #9
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No size issues on ours, but the mattress (full queen size), was not exactly the most comfortable thing that we've slept on. It didn't take long and we decided to put the sleep number bed mattress that was in our house, in the camper. We then purchased a new sleep number system for the house. After all, we sleep in the house a lot more nights than we sleep in the camper, so that part was a no brainer. Now, when we go camping, we have the same exact settings in the camper bed as we do in the house bed.
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Old 05-07-2018, 01:38 PM   #10
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+1 for adding a topper instead of replacing the mattress. It was DW's idea to try that first, and I was amazed how big a difference it made.


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