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Hot mattress

On our recent (maiden) trip from Iowa, we found that the mattress was really warm when we were ready for bed.  It would have been great if outside temps were near freezing, but not in this weather.  I think that I read that someone attached a foam board from Lowe's to the underside of the engine "lid".  I would appreciate any info on solutions.  This was not a problem with our Safari.
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8

Re: Hot mattress

Reply #1 –
Do you know if you still have the stock muffler?  Once I replaced that, the temperature of the bedroom and mattress significantly decreased, to the point of being almost exactly the same as the rest of the coach during the drive. 

It also allowed for at least an additional 50 lbs of cargo behind the rear wheels and resulted in room for an additional cabinet to be built in that space due to the sleek shape and size of the new muffler.  That stock muffler and the brackets for it are very heavy compared to the Magnaflow.

The new muffler itself was cheap, less than $100.  It was the design and welding to install it that took some brainpower and time.  Definitely the cheapest upgrade so far that was so exponentially beneficial.
Jennifer
2003 36' U295 (# 6070)
Thousand Oaks, CA

Re: Hot mattress

Reply #2 –
I know the PO replaced all the engine comp. reflective foam insulation + the mattress on ours.  No heat, even after a long day's cruise.
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Hot mattress

Reply #3 –
Does anyone run with  no muffler , just a straight pipe. Only asking because I've seen a few post on other forums about it. More hp and only minimal increase in noise ?

  As it relates to evacuating the exhaust heat out quicker verses trapping it in the muffler
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Hot mattress

Reply #4 –
Quote from: Bob & Sue –
Does anyone run with  no muffler , just a straight pipe. Only asking because I've seen a few post on other forums about it. More hp and only minimal increase in noise ?

Start a new thread  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Hot mattress

Reply #5 –
Afraid to open this post from the title. My e-mail sorter drops things with that kind of a title. Anyway, we had a sleep-number bed that got warm and was firmer after a long drive. Learned the hard way not to drain the extra pressure since it was cool and much flatter in the morning. Put the old muffler to rest and the heat went away for the most part. P.S. We now have a memory foam and really like it. The pressure in the sleep-number would change with atlitude...same problem with deflating and inflating.
Larry
1996 U295 36'
Build # 4805
Actually we sold it but just like to lurk

Re: Hot mattress

Reply #6 –
Sounds like an engine compartment venilator and more insulation could help. That, or parking much earlier than you expect to hit the sack, to allow things to cool off.
95 U300SE

Re: Hot mattress

Reply #7 –
Quote from: Sven and Kristi –
On our recent (maiden) trip from Iowa, we found that the mattress was really warm when we were ready for bed.  It would have been great if outside temps were near freezing, but not in this weather.  I think that I read that someone attached a foam board from Lowe's to the underside of the engine "lid".  I would appreciate any info on solutions.  This was not a problem with our Safari.
Ours was warm too....since the wife and I still work there have been many trips where we drive straight through from FL to MI taking turns driving and sleeping.  I replaced my old insulation in the engine compartment and used insulated foam board between the doghouse and mattress. No issues at all since then. 
Jeff & Carrie
2023 Geneva 31VA
1989 Grand Villa 36' ORED "The Button Pusher" - GONE 🥺

Re: Hot mattress

Reply #8 –

Adding a reflective insulation to the bottom of the bed is what you need.  The turbo and exhaust manifold on my C8.3 (and probably every other FT) are right under the mattress and contributed to an awful lot of heat to the bed.  Also check for any exhaust manifold leaks.

This stuff works well. 

Amazon.com: Thermo-Tec 14125 48" X 72" Two Sided Thermo Guard Flame Retardant...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Robert
Build # 5304
1998 34' U270 Cummins 6CTA8.3

Re: Hot mattress

Reply #9 –
Quote from: danieljeff545 –
Ours was warm too....since the wife and I still work there have been many trips where we drive straight through from FL to MI taking turns driving and sleeping.  I replaced my old insulation in the engine compartment and used insulated foam board between the doghouse and mattress. No issues at all since then. 
How thick is the foam board under your mattress and what kind of insulation did you use in the engine compartment?
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8

Re: Hot mattress

Reply #10 –
Quote from: rsihnhold –
Adding a reflective insulation to the bottom of the bed is what you need.  The turbo and exhaust manifold on my C8.3 (and probably every other FT) are right under the mattress and contributed to an awful lot of heat to the bed.  Also check for any exhaust manifold leaks.

This stuff works well. 

Amazon.com: Thermo-Tec 14125 48" X 72" Two Sided Thermo Guard Flame Retardant...
Did you put this under your mattress or install it over the engine?  If over the engine, did you remove the old insulation or sandwich the Thermo-tec between it and the bottom of the bed "lid"?
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8

Re: Hot mattress

Reply #11 –
Quote from: rvlooker –
Sounds like an engine compartment venilator and more insulation could help. That, or parking much earlier than you expect to hit the sack, to allow things to cool off.
I'd like to know more about the "engine compartment ventilator" - it would be good to blow the hot air out the back.  Do you have any information on this?
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8

Re: Hot mattress

Reply #12 –
Quote from: Bob & Sue –
Does anyone run with  no muffler , just a straight pipe. Only asking because I've seen a few post on other forums about it. More hp and only minimal increase in noise ?
Our coach has no muffler just a straight pipe. Was that way when we bought it. I don't find it excessively noisy, has a rather nice sound.

Roland
1993 U280 4341
2010 Jeep Liberty
The Pied Pipers

Re: Hot mattress

Reply #13 –
Plenty of various brand  resonators in use to replace muffler. Nice sound, lower back pressure
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: Hot mattress

Reply #14 –
Quote from: Sven and Kristi –
Did you put this under your mattress or install it over the engine?  If over the engine, did you remove the old insulation or sandwich the Thermo-tec between it and the bottom of the bed "lid"?

I'm pretty sure I posted pictures of it on here but I can't find them anymore (might have been on the old site and not transferred over?).  The old insulation was left in place and the heat reflective insulation mat was installed over the top of it with glue and washers and screws.  The edges were taped with aluminized tape.  There is no heat in the mattress after this was done.
Robert
Build # 5304
1998 34' U270 Cummins 6CTA8.3