Those of us that have Equal-i-zer weight distributing hitches are familiar with the process of checking WD setup by measuring at the front wheel well. I cannot speak for others, but I have ALWAYS had a very difficult time reading the tape measure, because the difference between the various measurements is so small. So I was elated to receive an offer from Equal-i-zer to purchase a new laser tool developed just for taking these measurements. It's called the OnTarget Towing Tool, and it's basically a laser measuring tool with a whole bunch of cool features built in.
So today, I had time to actually go give it a try and see if it was worth the money. My short answer is... it's okay. Well... better than okay. But I had some difficulties with it and I think there is enough margin of error to be cause for concern. In spite of that, I think the numbers I obtained in my test were very reasonable.
During my test, I only obtained one complete set of measurements. One set consists of measuring from the lip of the wheel well to the ground three times. First with the tow vehicle and trailer uncoupled (A), then with the trailer coupled and the weight on the Tow vehicle, but without WD engaged (B), and finally with the trailer coupled and the WD engaged (C). The percent of WD is calculated by dividing the difference between the first and third reading (C-A) , by the difference between the first and second reading (B-A) and multiplying by 100. If you want to see more about that, I am including a link below where you can watch a YouTube video.
So here are the results of my test...
Measurement A was 38.58 inches
Measurement B was 38.90 inches (+ 0.32 inches) with a tape measure I usually read a difference of 3/8" so this is reasonable.
Measurement C was 38.74 inches (+ 0.16 inches) with a tape measure I always looked for it to come back down at least 3/16" so again, this is reasonable.
One cool feature is that it will make the WD calculation for you. In this case it was 50% ((0.16/0.32)x100)
The next phase of my test was to assess my ability to make repeat measurements. So I took 10 measurements in a row with the Tow Vehicle in my garage on a level floor. Seven of the 10 measurements were exactly the same (38.19"). The other three were also the same, but 0.04 inches less than the other seven (38.15"). So I assumed that I could reasonably make measurements that are within +/- 0.04 inches of the "true" measurement. (i.e. margin of error).
I assumed that the numbers I obtained from the tool were "accurate", and then I plugged them into a spreadsheet and calculated the percentage of WD for each set of numbers, varying all of them within the margin of error. What I found is that if the "true" (A) was +0.04, and the true (B) was +0.04, and the true (C) was - 0.04 The percentage of WD calculated to 25%. (low extreme) When true (A) was -0.04, and true (B) was -0.04, and true (C) was +0.04, calculated WD was 75% (high extreme). More importantly, 20 out of 27 of the values fell between 35% and 65%. With numbers like these, I feel pretty confident in increasing the amount of WD from the hitch and I will do that the next time I plan to tow the trailer.
My only concerns with this instrument center around being able to take repeatable measurements, as you have to get the measurement in exactly the same spot each time. It comes with a handy target to aim the laser at and I found this to be very helpful. I also had a little trouble with inadvertently pushing buttons and having to start over. This is probably just a "needs practice" issue.
In addition to making the WD measurements, the tool will also measure distance, and calculate areas and volumes. I'm not sure what else it does as the instructions are very brief. Overall, I'm not disappointed.
Link to YouTube:
https://youtu.be/w9L-g9n-VPg
Measurements made during my "test"
Bob
So today, I had time to actually go give it a try and see if it was worth the money. My short answer is... it's okay. Well... better than okay. But I had some difficulties with it and I think there is enough margin of error to be cause for concern. In spite of that, I think the numbers I obtained in my test were very reasonable.
During my test, I only obtained one complete set of measurements. One set consists of measuring from the lip of the wheel well to the ground three times. First with the tow vehicle and trailer uncoupled (A), then with the trailer coupled and the weight on the Tow vehicle, but without WD engaged (B), and finally with the trailer coupled and the WD engaged (C). The percent of WD is calculated by dividing the difference between the first and third reading (C-A) , by the difference between the first and second reading (B-A) and multiplying by 100. If you want to see more about that, I am including a link below where you can watch a YouTube video.
So here are the results of my test...
Measurement A was 38.58 inches
Measurement B was 38.90 inches (+ 0.32 inches) with a tape measure I usually read a difference of 3/8" so this is reasonable.
Measurement C was 38.74 inches (+ 0.16 inches) with a tape measure I always looked for it to come back down at least 3/16" so again, this is reasonable.
One cool feature is that it will make the WD calculation for you. In this case it was 50% ((0.16/0.32)x100)
The next phase of my test was to assess my ability to make repeat measurements. So I took 10 measurements in a row with the Tow Vehicle in my garage on a level floor. Seven of the 10 measurements were exactly the same (38.19"). The other three were also the same, but 0.04 inches less than the other seven (38.15"). So I assumed that I could reasonably make measurements that are within +/- 0.04 inches of the "true" measurement. (i.e. margin of error).
I assumed that the numbers I obtained from the tool were "accurate", and then I plugged them into a spreadsheet and calculated the percentage of WD for each set of numbers, varying all of them within the margin of error. What I found is that if the "true" (A) was +0.04, and the true (B) was +0.04, and the true (C) was - 0.04 The percentage of WD calculated to 25%. (low extreme) When true (A) was -0.04, and true (B) was -0.04, and true (C) was +0.04, calculated WD was 75% (high extreme). More importantly, 20 out of 27 of the values fell between 35% and 65%. With numbers like these, I feel pretty confident in increasing the amount of WD from the hitch and I will do that the next time I plan to tow the trailer.
My only concerns with this instrument center around being able to take repeatable measurements, as you have to get the measurement in exactly the same spot each time. It comes with a handy target to aim the laser at and I found this to be very helpful. I also had a little trouble with inadvertently pushing buttons and having to start over. This is probably just a "needs practice" issue.
In addition to making the WD measurements, the tool will also measure distance, and calculate areas and volumes. I'm not sure what else it does as the instructions are very brief. Overall, I'm not disappointed.
Link to YouTube:
https://youtu.be/w9L-g9n-VPg
Measurements made during my "test"
Bob
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