Tire pressure Scamp 16'

[BatDude]

I added a tire pressure/temp sensor system to our Scamp for the winter trip. Wayne at Scamp suggested keeping tires around 48-49 lbs for smoother ride and sticker indicates cold pressure to be 50 lbs.

The sensor was set for 45 lbs as low and 55 lbs as high-pressure warnings.
When cold pressures are set to 50 lbs and traveling on Interstate 65-70 MPH pressures went up to 55 lbs on one warmer day. Cooler days pressures remained+/- 52-53 lbs. When we stopped to bleed a bit of air out the 55 lbs day to 50, all was well for towing, but then when we restarted the following day the cold temps were <45lbs and alarm screaming again.

Wow, a lot of fluctuations. There has been some discussions Re:filling with other gas vs. straight air for more stable pressures. Pondering efficacy/value of that.

Still on the learning curve. In the past w/o active data monitoring, I was oblivious to these wide pressure changes. Sort of like how many control (or not) their diabetes with little or no testing. This is why it is often referred to as the silent killer.

I will see how our Scamp pulls with new TV once it arrives.

[gordon2]

Those readings are similar to what I see with my TPS. 48,49,50 is within the limits of the accuracy so no worries there. In other words if someone tells you to inflate to 48 or 49 and it is supposed to be 50, most guages are not accurate enough to discern 49 from 50 so it makes no difference. (I also doubt that one or two PSI makes any discernible difference in ride quality)

On the other hand, 45 is too low and the recommended inflation is "cold inflation," i.e. before driving. So when the temps dip, the pressure lowers, as it will do according to Boyles law. It is common to need to add air when the weather changes drastically and the temps fall. On my car this only seems to happen first thing in the morning when I'm late for work and its cold, and usually snowing

Less often you will find the pressure too high after a sharp warm up and need to release just a little air. But base your inflation on "cold inflation," not afternoon readings or after driving.

One thing to note if your TPS also reads the tire's temperature... I have seen the reading skyrocket when the camper was parked with one of the tires in direct and intense sunlight. Those black tires really absorb the rays! The temp returned to close to the same as the other tire after a few minutes on the road after it was not in the sun all the time. So if the temp goes up, sunlight is one possible cause.. but still monitor and investigate if it the temp does not lower when expected.

[Paul O.]

My "unfairpoint" dropped the line on me, so I have to retype. I'll be brief. I got my TPMS a couple of years ago, and also learned a few things using it. By letting out 5psi at warm, you reduced the cold pressure by pretty much the same and got below the alarm. I set the low warning at 40, cold inflate about 48psi.

Nitrogen fill? Not worth the hassle, we are not on a race track. I have the TPMS to be warned about a fast leak (a nail or a sharp rock) which needs immediate attention, or a slow leak that can lead to overheating and a blowout, with many bad consequences.

[Darrin S]

Just curious what brand and model did you get.
Thanks Darrin

[Wayne Collins]

We had a 16 ft Scamp DLX Side Dinette. Fully loaded for travel it weighed about 2900 lb. that is 1450 lb per tire.
With ST185/80R13 tires we ran with 35 - 40 psi air pressure.
You don't need any fancy gizmos. Just stop after about 50 miles at high speeds, and feel the tires. If you can hold your hand on the side walls, they will be warm, you are good to go. And, BTW, your tires are rated for 65 MPH, max. ..unless you have special high speed tires.


50 psi. is only for if the tire is carrying the max load.
Looking at a LOAD/INFLATION chart -
If you have 185/80R13 tires:

30 psi = 1100 lb per tire and 2200 per axle
35 psi = 1200 and 2400 lb and this is the max for "B" rating tires
40 psi = 1300 and 2600
45 psi = 1400 and 2800
50 psi = 1480 and 2960 lb, the max for "C" rating tires

You must weigh the trailer as loaded for travel; and set the pressure accordingly.
50 psi will give you a harsh ride, a lot of bouncing. And the tires are more susceptible to damage from sharp edges, rocks, etc.

[BatDude]

Looks like I will reduce the low-pressure alarm on the unit and not run the tires up to 50 as cold temp pressure.

I did stop at a TSA Cat scale for a quick estimate of our rig.

Scamp platform was 2,420 lbs and TV +/- 4,800 lbs.
Since we were connected this was not a Scamp only weight and will look for an SKP smart weigh site on our winter travels.

The old Ford Freestyle is allegedly limited to max tongue wt. of 250 lbs and 2,100 tow weight due to the constant velocity transmission. The regular AUTOmatic trans version with the same frame and power plant had a 3K lb tow limit.

The new TV when it arrives with a class III load balancing factory installed receiver hitch has a max 5K lb tow weight with 500 lb tongue weight.

Cheers,

Bat Dude

[Paul O.]

Originally Posted by Darrin S

Just curious what brand and model did you get.
Thanks Darrin

This one, two sensors:
https://tsttruck.com/product/2-tire-...toring-system/
The truck, 2013 Tacoma, came with its own.

[Paul O.]

...actually stands for Continuously Variable Transmission. Here is a little video:

https://www.youtube.com/watch?v=PEq5_b4LWNY

[Darrin S]

Originally Posted by Paul O.

This one, two sensors:
https://tsttruck.com/product/2-tire-...toring-system/
The truck, 2013 Tacoma, came with its own.

Thanks Paul

[gordon2]

For two wheel TPS I bought and recommend the TST 507R from this seller.

You must put in metal valve stems if you have rubber ones.

---------

Originally Posted by Wayne Collins

..

50 psi. is only for if the tire is carrying the max load.
....
You must weigh the trailer as loaded for travel; and set the pressure accordingly.
50 psi will give you a harsh ride, a lot of bouncing. And the tires are more susceptible to damage from sharp edges, rocks, etc.

This has been argued a million times plus one, I think.

IMHO with a properly working torsion axle and assuming a typical Scamp which is maybe 70-90% of the tire's weight rating, the difference in ride is so negligible as to be inconsequential. Personally, I go with 50 PSI and my camper does not noticable bounce. If you were running at 50% or less of the tire's weight rating then that would be different.

The risk of a puncture might be slightly increased but again I think its negligible. On the other hand, under inflation is all too common and more often a higher risk. I would tread carefully (pun unintended) if you want to run lower pressure on a typical Scamp. Your milage may vary, both literally and figuratively.

[Darwin Maring]

We set the pressure at the required PSI and when the monitor beeps, we read it and understand what is going on and ignor the warning. Should there have been a problem we would know. For us - The false notification is acceptible to us. Should we not have the device(s) then with a real emergency we would be in real trouble.

[floyd]

Originally Posted by BatDude

I added a tire pressure/temp sensor system to our Scamp for the winter trip. Wayne at Scamp suggested keeping tires around 48-49 lbs for smoother ride and sticker indicates cold pressure to be 50 lbs.

The sensor was set for 45 lbs as low and 55 lbs as high-pressure warnings.
When cold pressures are set to 50 lbs and traveling on Interstate 65-70 MPH pressures went up to 55 lbs on one warmer day. Cooler days pressures remained+/- 52-53 lbs. When we stopped to bleed a bit of air out the 55 lbs day to 50, all was well for towing, but then when we restarted the following day the cold temps were <45lbs and alarm screaming again.

Wow, a lot of fluctuations. There has been some discussions Re:filling with other gas vs. straight air for more stable pressures. Pondering efficacy/value of that.

Still on the learning curve. In the past w/o active data monitoring, I was oblivious to these wide pressure changes. Sort of like how many control (or not) their diabetes with little or no testing. This is why it is often referred to as the silent killer.

I will see how our Scamp pulls with new TV once it arrives.

This discussion has been covered ad nauseum.
Minimum weight /pressure charts be d@^^ned...
Fill your tires with air and Set your pressure to 50PSI cold.
( plain black or chrome cap)


...
If you really wish to impress your neighbors at the campground... forget Nitrogen and use Xenon gas to inflate your tires... its inert, it costs a real fortune, and the name sounds "Xotic" (Use a bright blue valve stem cap)

Or you could try Radon, capture it in your basement... It might make your tires glow in the dark, adding to safety to balance out the possible effects of the radiation. (Use a Yellow valve stem cap)

Try Neon for a nostalgic look (red cap of course)

Try carbon dioxide, it has the advantage of sequestration and may even get you a government subsidy. ( clear blue cap)

Methane gas is a good choice, collect it from cows to reduce your guilt from eating beef. It might be embarrassing to reduce tire pressure when anyone else is around but you can always point to your neighbor and giggle! (brown cap)

There is always Helium which may make your tires squeal like Mickey Mouse when you have a flat, giving you fair warning! Possibly making less unsprung weight! (Alert Orange cap)

Don't bother with filling your tires with a vacuum there's nothing to it...
but it "sucks", run flat trailer tires are scarce, and even when its "perfect" you can only go 30"(towing with a Mercury)!

[BatDude]

I am using the TST 507 system with only 2 sensors.
I ordered from a Casitia website that offered the system with only 2 sensors rather than the full truck complement of 4-6-8 etc.

HTH

Bat Dude

[The Minimalist]

I recommend filling your tire with a gas mixture that is 80% Nitrogen.........air will serve as an adequate substitute.