Chassis and Tank Talk

[Geo.Lander]

I am planning on adding a slightly larger fuel tank on the passenger side, i was wonder if something like this is or this is just a bolt on affair?

I am also currently planning to move the air tanks into the center, I am not planning to change them out for Aluminium I don't think.

I have on order new parabolic spring sets both front and rear with 10mm lift (help with rear clearance) and new extended shocks to match, thoughts?

 

[VerMonsterRV]

Can I assume you are getting these from DFF? If so they are bolt in.

So, the fronts bolt in and increased our front ride height about 30mm. On ours the top of the front spring just touches the inside of the spring holder fitting. Does not look to be an issue but thought I would bring it up. The 30mm lift was due to more arc in the spring. What this does is slightly locate the front axle a bit forward. Once again does not look to be an issue but it does cause the steering wheel to not be centered, so you will need to do an adjustment of the linkage. I still need to do this.

With the rears we got the 4 leaf with a helper spring. We originally had about a 75mm spacer block with the factory springs. We had to remove that and use just a single 25mm spacer to get the ride height lower. DFF supplied us with a couple different spacer blocks, this was the thinnest. The chassis is now just about flat with a full load, just ever so slightly higher in the rear. This was what we had hoped to accomplish.

So, now I have mover onto a shock upgrade. I did replace the dead factory shocks with inexpensive Monroe shocks that "fit". I am looking into either custom Fox/King (custom USA) shocks or ones from Marquart in Germany. I am awaiting a quote from Marquart now and will start looking in the Fox/King route. The custom route will not be inexpensive so may wait until other projects are completed (like the turbo upgrade).

Now the diesel tank. What is your habitat design? I ask this because our tanks are on the passenger side just below our entry habitat entry door. The placement/design of the tanks makes entry steps difficult. We are fine with how they work but I wince when anyone that has reduced mobility tries to enter the habitat. So, if I had an unlimited budget I would have a single custom aluminum fuel tank built that would have an indented place for a better folding steps to be built and since it would be custom I would likely not lose any capacity. Really depends on budget but would definitely make building more substantial boarding steps easier. Also, if you look at the placement of our tanks I needed to make a spacer block to move the tanks away from the chassis to clear the leaf spring hangers. It was a simple 3"x5" rectangular steel box section, so that tank you linked to may or may not work. I would wait until your habitat is built and on and then take a look at how the tank could work (and how your budget is doing).

 

[DiploStrat]

FWIW - I have had the pleasure of examining Jon's truck and camper work. Everything that he has done is just that little bit better than my truck, so I would be very inclined to accept his counsel. (Of course, it is probably just Heather's influence ... )

 

[Geo.Lander]

Can I assume you are getting these from DFF? If so they are bolt in.

So, the fronts bolt in and increased our front ride height about 30mm. On ours the top of the front spring just touches the inside of the spring holder fitting. Does not look to be an issue but thought I would bring it up. The 30mm lift was due to more arc in the spring. What this does is slightly locate the front axle a bit forward. Once again does not look to be an issue but it does cause the steering wheel to not be centered, so you will need to do an adjustment of the linkage. I still need to do this.

With the rears we got the 4 leaf with a helper spring. We originally had about a 75mm spacer block with the factory springs. We had to remove that and use just a single 25mm spacer to get the ride height lower. DFF supplied us with a couple different spacer blocks, this was the thinnest. The chassis is now just about flat with a full load, just ever so slightly higher in the rear. This was what we had hoped to accomplish.

So, now I have mover onto a shock upgrade. I did replace the dead factory shocks with inexpensive Monroe shocks that "fit". I am looking into either custom Fox/King (custom USA) shocks or ones from Marquart in Germany. I am awaiting a quote from Marquart now and will start looking in the Fox/King route. The custom route will not be inexpensive so may wait until other projects are completed (like the turbo upgrade).

Now the diesel tank. What is your habitat design? I ask this because our tanks are on the passenger side just below our entry habitat entry door. The placement/design of the tanks makes entry steps difficult. We are fine with how they work but I wince when anyone that has reduced mobility tries to enter the habitat. So, if I had an unlimited budget I would have a single custom aluminum fuel tank built that would have an indented place for a better folding steps to be built and since it would be custom I would likely not lose any capacity. Really depends on budget but would definitely make building more substantial boarding steps easier. Also, if you look at the placement of our tanks I needed to make a spacer block to move the tanks away from the chassis to clear the leaf spring hangers. It was a simple 3"x5" rectangular steel box section, so that tank you linked to may or may not work. I would wait until your habitat is built and on and then take a look at how the tank could work (and how your budget is doing).

Hi Jon!

Thanks so much for this, yes DFF (thanks for putting me in contact, learning so much simply by following your thread and blog). He is speccing out some matching shocks for me too and Ive opted for a 10mm lift (instead of the standard 30-40mm). DFF seem to know the axle weights as they just asked my target weight (7500-8500 kgs) and as such designed a 3+1 system for the rear (whatever that means).

My box will be a 4.9m long ex-military radio box from the Danish military, Aigner will also design and build the sub-frame. I had thought to design and build a small deck on heavy duty Accuride rails depending on the clearances i have between the subframe and the chassis mounted components like the tank etc as you have mentioned. Would be nice to have a little deck I thought I have priced custom tanks too, think Ill need to settle for off the shelf (refurbished).

Can I ask how much the ride quality has increased with the parabolics? Not that much corrugated roads in Norway but we have our share of just plain crappy roads ones. The consensus seems to be to certainly add these and save weight at the same time and while I am optimizing the chassis anyway it seems like the right choice and time to do these changes.

 

[VerMonsterRV]

Hi Jon!

Thanks so much for this, yes DFF (thanks for putting me in contact, learning so much simply by following your thread and blog). He is speccing out some matching shocks for me too and Ive opted for a 10mm lift (instead of the standard 30-40mm). DFF seem to know the axle weights as they just asked my target weight (7500-8500 kgs) and as such designed a 3+1 system for the rear (whatever that means).

My box will be a 4.9m long ex-military radio box from the Danish military, Aigner will also design and build the sub-frame. I had thought to design and build a small deck on heavy duty Accuride rails depending on the clearances i have between the subframe and the chassis mounted components like the tank etc as you have mentioned. Would be nice to have a little deck I thought I have priced custom tanks too, think Ill need to settle for off the shelf (refurbished).

Can I ask how much the ride quality has increased with the parabolics? Not that much corrugated roads in Norway but we have our share of just plain crappy roads ones. The consensus seems to be to certainly add these and save weight at the same time and while I am optimizing the chassis anyway it seems like the right choice and time to do these changes.

Well, ride quality is subjective and our trucks is 32 years old (and I have only driven ours, so nothing else to compare against). After completing our build the rear helper springs were resting on the stoppers. So something needed to be done. After talking with DFF (Harald) he said they usually fitted parabolics onto converted trucks, they just ride better. The new rear springs took care of the sagging butt and to boot since the springs were actually not on the stoppers they provided some movement. So that was a success. Now move a few months along, the front springs were not sagging much and the ride height was ok. But, any bump would cause us to wince before we hit it. I mean any bump, even speed bumps. They were just so stiff and did not provide much articulation. So the decision to replace the fronts was a ride quality one. I have to say the ride is now much better, smaller bumps we don't slow for, bigger are not a huge deal. These springs articulate. But of course when you fix one thing you sometimes uncover other issues. Well the original front springs were so hard they had a better road feel at speed while driving. The newer softer ones wander a bit more, which I think points to poor shocks. So I have started down that path, it will likely be a month or more before I decide which way, I am slow to make decisions. Marquart (probably who Harald is going to work with, I have asked Christian at Marquart to contact him for our shocks) has just gotten back and 4 new custom shocks will be about 1050 euros + shipping. I need more details but I think they are tuned for our truck, but do not have external reservoirs (which the Fox/King ones would, though at a much higher price). Marquart's website is not the best for technical details.

I tried to tempt Diplostrat to make a drive west to meet up. Would be fun to drive our trucks back to back to compare the differences (if any).

Your 3 + 1 means 3 main leafs with a separate bottom leaf to act as an overload. In normal use the bottom leaf would never come into play. Only when highly loaded, hit a large bump or loaded up a single rear wheel offroad. Ours is a 4 + 1 setup probably do to the weight the motorcycle lift added. The leaf spring picture you posted does not have the overload leaf, guess they figure (and likely correctly) your load on the front axle changes way less than your rear (well in regular truck use, our use it is actually pretty static).

And yes, the new spring packs weigh less than the standard leaf packs. Especially the rears, the originals were pretty dang heavy.

 

[Sitec]

Both those tanks will just bolt on. However, I'd be slow to buy tanks or springs until you are well into your build. The reason I say this is because I have shifted air tanks, battery boxes, fuel tanks and re designed the muffler system all to make better use of space and to utilise every free inch of chassis space. There were a few things I bought early that I have since sold as they won't fit where I thought they were going to go. I'd also suggest settling on a layout early in the build, and plan as to where your Hab Box door is going to be early, because you will want to have space under that door for decent steps. I'd try and avoid having the door above the wheels. With the Hab Box sat on your chassis at the finished height, you can then set about filling the chassis space and buying tanks to suit gaps left. At this point you can also work out where grey tanks need to be in relation to where the shower is going to be in the Hab Box above.... You can site the gas cylinders in a locker under the kitchen... Once you have the box and side skirts on, tanks, batteries etc etc etc all roughly bolted where they need to be, you'll be a lot nearer to your finish weight. From this you can then decide what springs you need and how much lift you might want. Just my thoughts.

 

[Geo.Lander]

Both those tanks will just bolt on. However, I'd be slow to buy tanks or springs until you are well into your build. The reason I say this is because I have shifted air tanks, battery boxes, fuel tanks and re designed the muffler system all to make better use of space and to utilise every free inch of chassis space. There were a few things I bought early that I have since sold as they won't fit where I thought they were going to go. I'd also suggest settling on a layout early in the build, and plan as to where your Hab Box door is going to be early, because you will want to have space under that door for decent steps. I'd try and avoid having the door above the wheels. With the Hab Box sat on your chassis at the finished height, you can then set about filling the chassis space and buying tanks to suit gaps left. At this point you can also work out where grey tanks need to be in relation to where the shower is going to be in the Hab Box above.... You can site the gas cylinders in a locker under the kitchen... Once you have the box and side skirts on, tanks, batteries etc etc etc all roughly bolted where they need to be, you'll be a lot nearer to your finish weight. From this you can then decide what springs you need and how much lift you might want. Just my thoughts.

This is really good advice! thanks @Sitec! I will go that route and delay ordering the spring kits and tank. My plan was for a 1:1 render in sketckup but i do not have the exact dimensions yet for the hab and subframe.. aigner seem very busy at present and it seems work will not be getting started on the subframe until April

 

[grizzlyj]

Just to add a little to Sitecs wise comments, our old camper had a ladder that was light enough to sit on the floor inside the door to quickly and easily reach in, get, set up and climb in even when someone was parked up tight to us which they often did. We could also easily reach out from inside at night and pull it in before sleep.
Our current camper floor is higher, we now have a five year old so we chose to have steps not a ladder which take up more ground floor space when set up. These are quite heavy but much safer. We have a platform that slides out from under the camper floor that they clip onto, and can be set running to the front, rear or side depending on what the grond requires or again people parking too close. We can put a lightweight handrail on the platform too.
Some manufacturers ladders are set up to slide fully out from under the camper floor and then fold down, but need a lot of space to get them out before they can fold.
Ideally I would have a few ladder steps fixed within the architecture on the side of the chassis so I can hop in and out without the ladder which is often needed, and becomes a pain otherwise. But I can't because there's a fuel tank there, I'd have to remount it to get the depth needed. So I have a small and light step ladder on the floor inside to just kind of lean in place.
Cloud 9 has a nice way of getting in, and also means there is no metal connection from floor to truck avoiding ants etc walking in to some extent for instance, but I didn't have the space inside to lose to a well for steps.

 

[VerMonsterRV]

Just to add a little to Sitecs wise comments, our old camper had a ladder that was light enough to sit on the floor inside the door to quickly and easily reach in, get, set up and climb in even when someone was parked up tight to us which they often did. We could also easily reach out from inside at night and pull it in before sleep.
Our current camper floor is higher, we now have a five year old so we chose to have steps not a ladder which take up more ground floor space when set up. These are quite heavy but much safer. We have a platform that slides out from under the camper floor that they clip onto, and can be set running to the front, rear or side depending on what the grond requires or again people parking too close. We can put a lightweight handrail on the platform too.
Some manufacturers ladders are set up to slide fully out from under the camper floor and then fold down, but need a lot of space to get them out before they can fold.
Ideally I would have a few ladder steps fixed within the architecture on the side of the chassis so I can hop in and out without the ladder which is often needed, and becomes a pain otherwise. But I can't because there's a fuel tank there, I'd have to remount it to get the depth needed. So I have a small and light step ladder on the floor inside to just kind of lean in place.
Cloud 9 has a nice way of getting in, and also means there is no metal connection from floor to truck avoiding ants etc walking in to some extent for instance, but I didn't have the space inside to lose to a well for steps.

I looked into an entry like Neil did, it does add a bit of work/expense to the build but is really nice. We ended up with a compromise. We have a small (just wider than the door) sliding platform with 2 steps on it. Easy to pull out and we can both make the big step without anything else. If we are setup and feel like it we pull out a small aluminum 2 step ladder. In a perfect world I would have a custom aluminum tank built with a ladder recess. The platform/ladder would be actuated by opening the door or by an external switch. We saw a Unicat like that, nice setup but way beyond my skill level (and budget).

 

[Sitec]

Our steps are fully mounted. There are positives and negatives to this. The negatives are that you always have to park with space in mind as the steps are attached to the truck, and if you have to make a rapid departure from somewhere that might have turned hostile, you are going to wreck the steps and part of the truck... but in reality that is a small price to pay if the situation is bad.

The good points are that the steps are not in contact with the ground (as mentioned by grizzlj), you always have decent steps to climb, which is a must for us as my wife openly admits she's not flash on her feet!... and lastly the steps are always secured to the truck even when on rough ground.

Everyone will have different needs, but for us, the setup I have built suits well, as its easy to use, easy to fold out as it is gas strut assisted, and the dr can be closed with the steps up or down.

 

[grizzlyj]

The slight floor drop in Sitecs build may be enough to briefly hop in if needed without a ladder? Or just a small folding step like caravans (cough) use?
I did want a custom tank to fill the available space and with built in steps but ended up with a new take off plain 450 litre one. The custom fit might have given an extra 100l but at four times the cost!

 

[Neil]

We have found having the bottom step floating off the ground invaluable . On many occasions we have ended up parking on rough and uneven surfaces . In these circumstances the floating steps have worked well.

Neil

 

[Geo.Lander]

Thanks a bunch for the insight everyone, esp @Sitec and @VerMonsterRV for steering the ship so to speak!

So we have a schedule and the FD box is coming off the chassis next weekend (hopefully), seems we are looking at breaking even with price of aluminium these days, the transport costs to the recycling factory and crane taking up most of the budget.

One thing I have to think about is where I am going to place the batteries after the FD cab is removed? Where do people relocate these while working with their base chassis. I will need it to be driveable for the time being because the workshop we had lined up was not suitable in the end.. still looking (with vertical clearance being the biggest issue).

 

[Madoxen]

the workshop we had lined up was not suitable in the end.. still looking (with vertical clearance being the biggest issue

We had this same issue we have lots of space but all at a max of 2.5 mtr vertical. Tryed a cheap marque type tent but the 1st wind that came along shredded the whole thing. Which left me needing to do something a little more permanent.

I hope you do find a suitable and well priced space to work in as trying to do it in the rain wind dust dark is doable but realy not as productive as a dedicated space.

 

[Sitec]

I'd sit your batteries on a piece of timber atop the chassis rails for now, and use the existing leads (having carefully removed them from the FD body). The earth to the chassis can be bolted temporarily to any hole on the chassis or trans, the short battery link wire should still be fine and the lead to the starter should reach. One thing worth checking at this point is that the engine and trans have a decent earth strap linking them to the chassis... If not your earth can become the throttle cable, gear linkage, props or all manner of other things that are not ideal.