Revived Trailer Tire Thread (formerly on the 5th Wheel Forum

Here is the data from this weekend. I went to Flying Jay today and created 4 new fresh sets of weights.

The camper was filled with fresh water. 32 gallon fresh tank over the front axle, 6 gallon HW heater plus water in the lines = 42 gallons total.

There is some scale error in these numbers. This is normal for semi scales. Here is the raw Data. All numbers are in pounds.

TV & TT with WD engaged

TV Front Axle: 4,020
TV Rear Axle: 5,480
TT Axles: 8,300
Gross Combined weight: 17,800

TV & TT with "NO" WD
TV Front Axle: 3,620
TV Rear Axle: 6,040
TT Axles: 8,120
Gross Combined weight: 17,780

TV & TT with WD engged - TT axles split on 2 scales.
TV Front Axle: Front of TV off the scale
TV Rear Axle: 5,500
TT Front Axle: 4,340
TT Rear Axle: 4,040

TV Only
TV Front Axle: 4,100
TV Rear Axle: 3,760
TV Gross weight: 7,860

I also redid all the force jack figures with fresh water. I was trying to find the 300# plus pound error. I made it better but cannot get it to match the Cat scale numbers. Some of this may be the rubber equalizer and the method. Today I saw the wheel load change right before my eyes. Watching the force gage it would slowly drop, in some cases by 200#. Finally figured it out with my calipers across the EZ flex equalizer. At time zero the weight was the highest and the rubber not as compressed. Then after a minute or two it changed and the equalizer came together more. That changes the axle loads. Jacking the camper up and letting it down the rubber flexes until it settles. The force jack is weighing heavy on the axles so it is a safer number in this location. I was able to get the force jack to within 220# total verses the Cat scale axle numbers.



Here is a larger one, click it once it fires it will get bigger: Larger on Photo Bucket

If 15% reserve per location is the need, I have 3 tires locations not meeting this.

I also learned I am heavier then my last weight slip. I added hanger upgrades and a ladder and holder under the camper. And I'm sure some other things. It all adds up. The biggest eye opener was the loaded tongue weight. By using the force jack and a Sherline tongue scale it comes out at 1,500# here in my yard. Doing the math on the Cat scale slips comes out to be 1,800#. I have yet to figure out this difference since the force jack is weighing heavy at the axles and the Sherline matches it. I did measure the static load radius on each location just for data. It for sure is not conclusive.

New tires and rims will be in my future. The decision now comes down to E load range ST's in 15" that fit the camper or bit the bullet and go to 16" LT commercial truck tires and deal with the raising the camper. Both can do the loads with reserve however the commercial truck tire may be better in the reduction to cuts and other road hazards. These ST's sure seemed to get cuts which must be from camp ground stones and my driveway. Spending all this money and not addressing that keeps pushing me to the commercial tire.

Anyone seeing anything I missed please point it out.

A take away from this is direct to CapriRacers point. You need to know each wheels actual weight. Some how this needs to be an easier process then how I did it but this is what I had to work with.

I am also fortunate I have a camper built with the running gear to take the full GVWR of the camper. And even that is not enough if we want 15% or higher reserve capacity. Those who do not have this feature are even more at risk of being at or above the max of the tire in one or more locations.

Tireman9 and I are trying to work out something to analysis my failed tire to see if we can add to running it at only 12% reserve may or may not of affected it.

Hope this helps someone else working through this.

Thanks

John