BeefCake's build...a roll your own Earthroamerish family expo rig

IdaSHO

IDACAMPER
With that much flex, I dont think you have any choice other than going to a torsion free mount of some kind.

Personally, I like a 3-point mount for "light" campers, as in <5000lbs
Larger than that and I see a substantial subframe and spring mounts working.

I still have the now 5+ year old thread going over on Pirate.
Any and all updates are being posted over there.
As time between projects allows, Im working on designing a bed for the new truck to carry the custom camper.

This is where Im headed, to give you some ideas.

Basic 3-point mount setup.

Front will be bolted down.
Rear will involve completely boxing in the rear most part of the frame rails, and will be completely welded.

SD00016.JPG


Then the bed framing will rest on the subframe. This time Im pushing the camper 24" back on the chassis, to make room for a large gear locker at the front.

SD0008.JPG



Lots of small details to be included obviously, but thats the gist of the simple 3-point mount setup.

Pivots will be bushings, currently have my eyes on something like these

poly_bushing_sleeve_kit_assembly_tmr_customs_2.jpg


http://bustedknuckleoffroad.com/30-...-5-8-BOLT-30-bushing-and-housing-5-8-bolt.htm
 

lostih

Observer
Very cool. Mind if I ask a couple questions?

1. Why do the subframe instead of just putting the bed cross pieces flush with the sub frame? I'm sure you have a reason...just curious.

2. Some of my admittedly light reading on these mount systems has had me thinking about how I'd attach it to the frame to minimize stresses (ala Doug Hackney's stuff). In my mind that rear pivot should be right above the rear spring hanger so that the load flows directly down into the suspension without really stressing the frame rails. For the front I think just making sure there are good and long (12"+) mounts on the frame should do the trick. What are your thoughts on that?
 

IdaSHO

IDACAMPER
Happy to answer questions

1.

Calcs I did also involved max tire stuff during articulation with the stock suspension and 35" tires.
This gave me a measurement relative to the truck chassis to work with.
If the measurement was closer to chassis height, the flatbed frame would have been worked into the subframe ad the entire thing would be lower.
I did this with the current setup on the old truck, but it isnt running 35's

There are additional reasons as well. An aux fuel tank built into the bed, the front gear locker, as well as slide out stairs, all played a part in the design.
The aux fuel tank will be supported by the subframe, and the flatbed framing will provide adequate space for filler tube, vent, and sending unit hardware.
The gear locker had a certain height it needed to be for certain items it will house, and I wanted it low, but also not chassis mounted.
The front portion of the subframe will support the gear locker, and allow it to flex with the bed.
With the bed on top of the subframe, I will be able to arrange the flatbed framing to accommodate the stairs, that will slide in from the side between frame members.

2.

The front mount should distribute the weight as much as you can front to rear.
Also important is where that weight is placed on the chassis. With an open C-channel, the weight must be placed on top of the chassis, as apposed to mounts on the side, to prevent the weight from twisting the chassis.
So combining both left and right mounts into one piece of hardware is important, and webbing mounts should be avoided.

Rear mount vs leaf spring location...
I understand the reasoning behind the concerns, but I dont see the worry.
Most "light" trucks have considerable cross-members behind the rear axle that tie things together very well.
And if the camper unit is balanced weight wise correctly, the most weight should be considerably forward anyhow.

As it is, at least on my superduty, the rear most portion of the chassis is just 6" or so from the leaf spring hanger.
And loads of cross-member, as well as the chassis mounted class 5 hitch.

Lots of steel back there.

SD00010.jpg
 

lostih

Observer
I did have to build adapters. Also, while these are similar to mrap wheels, they are slightly different in that they have a more neutral offset. These wheels are also only 8.5&#8221; wide instead of the 10-11 of the mrap. I wasn't thrilled about running adapters until I realized from the factory the truck comes with one on the front. I think they should hold up fine, but it is one of the reasons I'm trying to drive the truck as much as I can right now to make sure everything is good to go.
 

lostih

Observer
Oh yeah...drives totally normal. I think most trucks have an inch or so difference between front and rear stock. Did my first freeway drive with the MPT's this morning and am shocked how quite they are. There is a barely distinguishable hum from them...certianly no more than the warn out Nittos I took off. We'll see how they do once they are broken in a bit more...
 

java

Expedition Leader
Very nice! Glad to see more local guys doing big trucks! I'm up in Seattle.

Im interested in those wheels too, I like them beeter than the MRAP's as I want to run the same smaller tires as well.

However I run into bolt pattern issues, mine is 10x225, and the stryker wheels are 8x275, not sure there is enough meat there to make an adapter plate.
 

lostih

Observer
Hi Java! I've read a bunch of your build too...thanks for commenting. My truck was 10x225 as well. I'm not sure if the Fords are the same, but on mine there was a stock dually wheel adapter that was removable on the front. This left a smaller ten bolt pattern that made it possible to build a flat plate adapter that works well. If you look at some of the close up pics of the wheels in the fender flare post you'll see I use that smaller bolt pattern and then the giant 8 lug Kodiak pattern on the adapter. They were pretty straightforward to make on big lathe. And now I have the added bonus of rolling down the road with an entire hardware store's worth of nuts bolted to my wheels. I think my front wheels have 42 bolts on them!

For the rear it gets trickier as the bore of the Stryker wheels is right around 225 mm so the stock ram bolt pattern right on the bore. I ended up machining new centers for the wheels out of 7075 aluminum that pressed in and then drilled the ten lug pattern through both the new center and original rim. The new center was also thicker than the wheel so that it is kind of a top hat shape and has a flange that sticks out past the inner bolt pattern. Kind of hard to explain, but it seems to be working well. I also added a large plate behind the wheel to increase the diameter of the mounting surface. I swear I took pics of this but can't seem to find them at the moment.
 

java

Expedition Leader
Ah I see, yes my front end should have the adapter as well (same front axle? Super 60?)

What is the track width difference? From my measurements (awhile ago now) the stryker wheels were very close to being able to flip flop front to rear with a 1" adapter plate on them.

Any more pics of the rears?

Where did you find the wheels? I have not had much luck finding any (or any info really even!).
 

lostih

Observer
I think dodge uses a magna axle or something like that in the front...so could be different. I have .375 or .5" plate stacked behind the wheels and my track is darn close to spot on.

For the wheels...I sold a set to Cowpig...you might check with him and see if they are going to work out for his build or not as he is close to you up north. If not PM me and I can try and dig up contact info for the guy I bought them from...I think he had a few left.
 

lostih

Observer
Thanks! So you really just pressed new centers in? Hmmm. PM'ed you!

Well...they are a very light press fit. You can easily tap them out. The idea is that they hold the wheel perfectly centered while the lugs tighten the snot out of the adapter/wheel sandwich. I had lots of debate with friends (machinists and engineers) about what holds a wheel in position in a torsional sense...is it the shear force of the lugs or the induced friction load by the clamping pressure of the lugs. I think its the friction load. If my theory is correct I should have no problems. If I'm wrong...well...that'll suck.
 

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