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Originally Posted by thewitzclan
.... we just had some bouncing. It's hard to explain. We figured it may have had something to do with the roads because it wasn't happening all the time. I think it may also have been something to do with the air pressure in the tires. The tires say 65 PSI and we were at about 58 PSI, and we weren't at full load capacity. I'm thinking we should have had the air pressure in the tires a little lower. Am I wrong? Should we have had 65 PSI?
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Both 58PSI and 65PSI were probably way too much. In post #2 of this thread,
http://www.trailmanorowners.com/foru...ead.php?t=3357
I used the 3023 as an example of tuning down the tire PSI to match your load. The 3023 is the "worst case" of standard TM models for needing reduced tire pressure. (My non-standard 2619 is even more extreme, but that's because I requested the big axle.)
If you were loaded light, but had your water tank full, you were probably at about 3800-4100 lbs total load. (TM doesn't count the A/C in their "dry weight" figure, you DO need to count it.) If your WDH was set (properly) to torque about 1/3 of the tongue weight back on the TM axle, then roughly 200-300 lbs was being taken by the TV via the tongue. So you had only 1700-1900 lbs on each tire. According to Goodyear's chart for the Marathon ST225/75R15, this would call for 45 PSI or even less.
Perhaps as little as 35 PSI, though I
wouldn't go down that far-- the Dexter axle has a lot of Spring, and you definitely don't want to be too low. But 58 PSI is way too hard, for sure.
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B&D have a 2720 (14" rims, I didn't put that chart into my post. But it is in the pdf:
http://www.goodyear.com/rv/pdf/rv_inflation.pdf
That gives them about 800 lbs less load capacity than you have. According to Goodyear, the maximum load for the ST215/75R14 tire is only 1870 lbs at 50 PSI. And of course, the Dexter with the 14" wheels is officially good for only 3500 lbs. Starting from 50 PSI, rather than 65, leaves a lot less room for "tuning". And the small Dexter has a lot more flex. So even empty, I'd never dream of putting a standard 2619 or 2720 tire below 40 PSI minimum. B&D running at max (50 PSI) is WAY closer to "optimal" than you running at 58 PSI on your much larger and more load-capable tire.
Is the small tire the ST215, or the ST205? The ST205 obviously needs MORE air pressure, loosing about 100 lbs load capacity at each PSI value in the table (in comparison with the wider tire). With either tire, you hit the Dexter limit before you hit the tire limit.
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More recently, Goodyear has allowed people to add up to 10 lbs, even exceeding the 65 lb limit, for driving at high speeds (on freeways). But this should only be done on smooth pavements, such as the Interstates.
If you're not using Marathons, or Goodyear's newer tire, then these numbers don't apply-- be VERY conservative about reducing pressure to match load with other brands.
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The other thing which can lead to excessive bouncing is insufficient torque on the WDH. If there's too much load on the TV rear tire, that's terrible at both ends: Your front tires, the ones you need for STEERING and BRAKING, don't have a fair share of the weight, that's REALLY BAD, and the TM tires are also a little lighter than they should be, causing a small increase in tendency to "bounce". Do you measure your TV height changes, or do you only guess? I'd measure carefully, at least once.
Getting ready for our first trip.
. We get condensation on the walls with 4 people sleeping/breathing in the TM, especially if it's raining. We just wipe down the walls when they need it, and sometimes place dry towels at the bottom of the walls in the rear bed (that seems to be the worst place for the condensation). 
3023 should use *MUCH* lower tire PSI, most of the time
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