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Old 08-10-2018, 07:07 PM
nick_m
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What's your CG zone?

Hello Campers,

This is a follow-up to my previous post regarding lack of TC certification. I'm trying to determine the truck loading values for my rig, but it looks like there are too many variables to solve for both zone and max weight (you can artificially reduce the max load by expanding the zone too far forward). The cert sheet that SDcrewzer was kind enough to post showed a 15" zone, presumably from the rear axle, and I recall someone else having mentioned a 15" zone. If anyone knows the formula, I'd love to hear it. Otherwise, if you have your cert sheet handy, could you tell me the offsets, and whether they're based on the rear axle? I can determine the loads based on where my camper has to sit (12" fwd of axle), but I'd like to see if Ford simply uses a fixed 15" zone.

BTW, the dealer said Ford was unable/unwilling to generate the values even if I upgraded the front spring to 6000 lb (the only piece missing from the TC option). I understand the liability concerns, but it's unfortunate, since making that information available would help their customers drive a safer setup.

Thanks!
Nick
 
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Old 08-11-2018, 09:59 AM
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Nick,

This thread is not getting a lot of hits and my thought is because most of us or nearly all do not worry that much about zone placement. The TC manufacturers have a lot of information out there about placement and it all seems to say the same thing in my estimation. You want the COG ahead of the rear axle.Conventional wisdom says with a long bed truck very little weight is transferred to the front axle and with a short bed no weight at all. If you put a camper made for a long bed on a short bed truck, your COG will be further back than would be ideal (although plenty of folks do it).

From the git-go in your earlier thread I had no worry at all that your truck was suitable for hauling a TC and I wonder if the point being raised here is worth very much consideration. I load my Hallmark as far forward as I can without the camper bashing the truck taillights and fasten it down. I replaced the bounce stops on my truck with Super Springs and used the stops I took off fastening them to the Happijjac stabilzer bar that connects my right and left tie downs. That makes the stops almost perfect length, and that's about it. I guess I might be underthinking it, but I am curious how many folks worry that much about positioning beyond what I do.
 
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Old 08-11-2018, 02:15 PM
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RV_Tech,

Thanks for chiming in; you're point is well taken. Combine moderate OCD with a career in precision measurement (where cert sheets are everything) and you can develop an obsession with metrics.

I was taught by the TC dealer to load the camper with the bumper pads touching, so I thought that was standard practice. I'm (obviously) still learning...

Nick
 
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Old 08-11-2018, 02:28 PM
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Nick, here's the thing and this is absolutely not a slam, but sometimes FTE drives me crazy because folks do seem to go OCD and they do it on topics I know backwards and forwards having seen them dozens of times in my work. In this case, I honestly don't think Ford 's slip of paper makes a bit of difference which is what I think you are also seeing on RV Net in their truck camper forum.

Suppose you get another 50 pounds one way or another on our front or rear axle, how will you ever know and are you certain you will load the same way each time? As you follow the various truck camper forums you will find folks who stop and continually readjust their camper to make sure it is absolutely centered. I don't and if mine shifts a half inch one way or another I really don't care. My load is secure, my truck handles it great, and I think the factors that make the most sense are the ones in the real world. So far from I have seen in your posts, the last thing in the world I am worried about is you doing something crazy! Just a hunch!
 
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Old 08-11-2018, 04:58 PM
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Originally Posted by RV_Tech View Post
Nick, here's the thing and this is absolutely not a slam, but sometimes FTE drives me crazy because folks do seem to go OCD and they do it on topics I know backwards and forwards having seen them dozens of times in my work. In this case, I honestly don't think Ford 's slip of paper makes a bit of difference which is what I think you are also seeing on RV Net in their truck camper forum.

Suppose you get another 50 pounds one way or another on our front or rear axle, how will you ever know and are you certain you will load the same way each time? As you follow the various truck camper forums you will find folks who stop and continually readjust their camper to make sure it is absolutely centered. I don't and if mine shifts a half inch one way or another I really don't care. My load is secure, my truck handles it great, and I think the factors that make the most sense are the ones in the real world. So far from I have seen in your posts, the last thing in the world I am worried about is you doing something crazy! Just a hunch!
RV_Tech,

No slam taken, and I appreciate your candor. Good hunch, by the way.

The swing outs just arrived, so I'm hoping to take a first test drive tomorrow.

Thanks for all the help!
Nick
 
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Old 08-13-2018, 12:39 PM
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Originally Posted by nick_m View Post
The swing outs just arrived, so I'm hoping to take a first test drive tomorrow.
Nick
How'd the first drive go? I've been following some of your questions as well. Thanks for asking, as many folks will learn along with you or in the future.
 
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Old 08-13-2018, 01:05 PM
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For those who didn't know these existed and I sure didn't, but already shared it with Nick on another site, Ford now has PDFs of their truck camper loading recommendations for 2017 and 2018 trucks.

Here are the URL: The first one is for the 17s, the second for the 18s. http://www.fordservicecontent.com/fo...er-Loading.pdf and http://www.fordservicecontent.com/fo...er-Loading.pdf
 
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Old 08-13-2018, 05:27 PM
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Originally Posted by Alaskan_Warbird View Post
How'd the first drive go? I've been following some of your questions as well. Thanks for asking, as many folks will learn along with you or in the future.
Alaskan_Warbird,

The drive went great! Thanks for asking. The swing outs went on without a hitch, and I dodged a bullet on Ford's new bumper design. On some campers, the raised end of the bumper requires modification of the sewer drain. I had to reroute a propane takeoff line under rather than over the pipe, but otherwise it was a perfect fit even with the camper all the way forward.

I added Stableloads on the lowers, and the sway is minimal. I haven't run without them yet, so I can't quantify the improvement. Even through the roundabouts - I have 5 between home and the freeway - there's very little roll. That used to be a white knuckle affair in my SRW. I might go ahead and do the uppers, since they're not yet engaged. As far as the camper certification goes, as RV_Tech points out, the loading documents have all the information a data junkie could ever want. The neat thing is that the dealer agreed to upgrade the springs to 6000 lbs to bring it to camper spec. That's service!

By the way, is that license real or Photoshopped?

Thanks again for the help.
Nick
 
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Old 08-13-2018, 06:19 PM
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Good to hear! That's my real license plate. I've been in IT and into computers most of my life - the 'F' doesn't actually refer to Ford.
 
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Old 08-13-2018, 06:57 PM
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Originally Posted by Alaskan_Warbird View Post
Good to hear! That's my real license plate. I've been in IT and into computers most of my life - the 'F' doesn't actually refer to Ford.
Oh, I'm familiar with the term - that's why I asked I was a software developer back in the day. Now I develop training videos because no one would read our "Fine" manuals, but everyone will go to Youtube for info.
 
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Old 08-13-2018, 07:11 PM
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Originally Posted by nick_m View Post
Oh, I'm familiar with the term - that's why I asked I was a software developer back in the day. Now I develop training videos because no one would read our "Fine" manuals, but everyone will go to Youtube for info.
Awesome. My first program was on an Apple IIe, in BASIC. I got into all of this back in 1982 after watching TRON. Started modding cases, fans, overclocking (before it became automated), and hacking (mostly white hat). Don't call myself a programmer anymore but am still heavily involved in IT, mainly in security, and system and database administration. Fun times.

Side note: I couldn't believe the DMV let me have the plates when I discovered them available on their web site many years ago. They cause quite a bit of envy from those in the know.
 
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Old 08-13-2018, 07:28 PM
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Originally Posted by Alaskan_Warbird View Post
Awesome. My first program was on an Apple IIe, in BASIC. I got into all of this back in 1982 after watching TRON. Started modding cases, fans, overclocking (before it became automated), and hacking (mostly white hat). Don't call myself a programmer anymore but am still heavily involved in IT, mainly in security, and system and database administration. Fun times.

Side note: I couldn't believe the DMV let me have the plates when I discovered them available on their web site many years ago. They cause quite a bit of envy from those in the know.
No kidding! Someone at the DMV was asleep. Definitely envious.

In 1982 I was coding in FORTRAN on punch card machines (not fun times). We sound like the couple of old tech geeks that we are. +1 on Tron (but only the original).
 
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Old 08-14-2018, 11:26 PM
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I think the CG discussion is rather academic when looking at a major manufacturer TC. It only applies under one set condition, and is completely different during real world use. Sure, if you are building your own you need to consider nominal CG, but for buying one that has already been engineered, the only real thing you need to do is buy enough truck to haul the camper.
Real world example (varies by design of course). Load the truck up for three or four days of boondocking. Fridge full, extra beer, water tank full, grey and black empty. CG is well forward of the axle. Now drive way into the mountains and chill for a few days. Fresh water tank (in front of axle) gets transferrred to the grey and black tanks( behind the axle), and the fridge and food get emptied (in front of axle). You have easily removed 800lb+ from in front of the axle and added 500lb behind the axle. The CG is waaay different, and possibly behind the axle now. Of course manufacturers say donít drive with grey and black full, because the CG is not a static point in real world use (I guess unless you use full hookups at every stop, but what TC does that?).
The only real world solution is to have enough truck to handle the large, variable weight. Donít sweat the CG, donít sweat a paper cert, try to stay within reasonable limits. If you donít have significant reserve capacity in your truck, consider not allowing grey and black to get full before leaving your spot, or shifting heavy gear forward (and low) when you leave to offset the waste tanks.
 
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Old 08-15-2018, 10:52 AM
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Originally Posted by nuctrooper View Post
I think the CG discussion is rather academic when looking at a major manufacturer TC. It only applies under one set condition, and is completely different during real world use. Sure, if you are building your own you need to consider nominal CG, but for buying one that has already been engineered, the only real thing you need to do is buy enough truck to haul the camper.
Real world example (varies by design of course). Load the truck up for three or four days of boondocking. Fridge full, extra beer, water tank full, grey and black empty. CG is well forward of the axle. Now drive way into the mountains and chill for a few days. Fresh water tank (in front of axle) gets transferrred to the grey and black tanks( behind the axle), and the fridge and food get emptied (in front of axle). You have easily removed 800lb+ from in front of the axle and added 500lb behind the axle. The CG is waaay different, and possibly behind the axle now. Of course manufacturers say donít drive with grey and black full, because the CG is not a static point in real world use (I guess unless you use full hookups at every stop, but what TC does that?).
The only real world solution is to have enough truck to handle the large, variable weight. Donít sweat the CG, donít sweat a paper cert, try to stay within reasonable limits. If you donít have significant reserve capacity in your truck, consider not allowing grey and black to get full before leaving your spot, or shifting heavy gear forward (and low) when you leave to offset the waste tanks.
I wasn't sweating - honestly! I just wanted to know Ford's opinion, or as Alaskan_Warbird might say, I wanted to Read The "Ford" Document. With the 6000 lb springs up front, I can find what I'd like to know from the document that ardvark provided, and I'm sure I have "enough truck" to cover my needs, now and in the foreseeable future.
 
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Old 08-15-2018, 04:58 PM
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Originally Posted by nick_m View Post
I wasn't sweating - honestly! I just wanted to know Ford's opinion, or as Alaskan_Warbird might say, I wanted to Read The "Ford" Document. With the 6000 lb springs up front, I can find what I'd like to know from the document that ardvark provided, and I'm sure I have "enough truck" to cover my needs, now and in the foreseeable future.
You certainly have enough truck! Load it up and have fun! Wouldnít sweat one number difference in front springs at all.
 
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