2004 E450 Bus Build
 

Hi all,

thought it made sense to start a new thread for the project I've been rolling around in my head because I actually have a specific vehicle now.

I picked up a 2004 Eldorado Aerotech shuttle bus - this is based on the E450 superduty chassis. I think it has a lot of potential - it has a 6.0L diesel (while it is the powerstroke that many have had issues with, this bus was fleet maintained and the E series 6.0L was detuned compared to the F series and so lower boost, lower fuel cutoff, etc.

Eldorado also used a composite fiberglass shell for the entire bus section - it is 1 piece from the cab back - and it is a honeycomb construction - so light, tough and pretty good insulation.

Stock, it appears i have a 4.10 rear, and the "happy spot" for RPM/Fuel is ~1900 RPM which currently is ~58 mph. highway mileage is reported on fuelly as between 10 and 20 mpg, but, when i visited some of the various forums they tend to report around 12 city, and 16-18 highway as configured from factory.

it.. kinda looks like this transmission has 2 ranges for each gear? i'm not sure

my ratios are listed as follows:
Max Min
1st: 3.09, 2.71
2nd:2.20, 1.54
3rd: 1.54,1.00
4th: 1.00, 0.71
5th: 0.71, 0.71

i may be able to get different rear gears as low as potentially 3.08 (probably a bit to high for usability - but maybe not since i do not plan on any towing?)

i'm not sure if this is something that the controllers will decide on, or if there is a low/high range selection or if i'm just reading too much into this? - i haven't seen ratios listed like that before (but I've also not looked at vehicles of this size before)

Eldorado seems like they made some effort at aero, and, being a single piece composite monocoque shell it is significantly lighter than it's metal contemporaries (plus, subjectively, it looks better :thumbup:) I'm thinking I've got some real opportunity to enhance the aerodynamics and mechanicals to be a relatively efficient package.

i'm planning on adding a boat tail with a platform bed in the rear, serves dual function of giving me a "master suite" and some presumably better aerodynamics - i'm alsp planning on stripping the big mirrors in favor of cameras with the mounts intact and mirrors stowed for emergencies - they attach with a couple of screws so i think i can have a block off plate using the same screws to quickly revert them if needed.

i suspect that the bulkhead where the destination sign would normally go might need to be trimmed/eliminated. I kinda already have skirting on the bottom sides, so i'm not sure in the front if i should look into an air dam or diffuser or maybe a pan on the bottom?

a pan would serve double duty to protect tanks and wiring, etc. that likely will be stored under the frame rails.

since the interior shell is already finished and a honeycomb composite - I'm not sure if i'll need to add any insulation before furring strips for framing, the thermal performance might already be pretty good - that'll save money and weight.

it has rear AC but the condenser is located under the bus instead of on the roof, so no custom blisters need to be added for me!

Consensus is: keep rpm under 2000 for max economy. Other than that those are sweet busses, but the rear AC kinda sucks. Perhaps not enough cool air flow. Needs tufting.

The transmission will be a 5-speed, single shifting between gears, the torque converter will lock up in every gear except 1st.

I wouldn't go to 3.08 gearing, 3.55 would be better, you could change the rear wheels to srw, then put wheel arch covers.

You do what you want, just my thoughts after working at a Ford dealer in parts and service for 26 years and counting...just my two cents, adjust for inflation, just my 1/2 cent:D:D

yeah, that is what i'd read as well. I was initially worried about the 6.0 because it has 175K miles, but based on what i've read so far they are generally considered to be a really solid motor in the E series because they aren't pushing performance out of it the way they were with the F series so that makes me happy, because that thing is shoe horned in there :p

i'll be driving it 2 hours home either friday or saturday so i'll be able to get at least a little bit of a feel for the economy (at least as much as the lie-o-meter can say) but ultimately, i intend to get something like a scan gauge or ultra gauge - it seems that i'll want to keep an eye on some temperatures that aren't OEM gauges so i'll need something to do that, what i haven't decided is do i want to have individual gauges, a screen like the xgauge/ultra gauge or some kind of combo?:confused:

Other ratios listed are for the 4 speed. That's what E450s got in 2004 when they had a gas engine.

so, which is the ones i should expect, min or max?

So - i doubt i need duals for my payload (but i can weigh it and verify) but 2 less wheels and tires to deal with would be just fine by me

The double wheel rear axle is a wider axle than a single wheel rear axle set up. So no, you can't safely take a wheel off each side as you have a huge offset on those dually wheels. With just one wheel (with a huge offset) hanging off the centerline of the bearing you create a lot of stress on the bearings and hub. You might be able to get a single rear axle wheel on it from a different vehicle. Those have about a 0 - 1" offset. You would have to run a load E range tire for the weight.

The ride will get squirrely at speed since the total width of the body will now be much wider than the tire path width. The extra track width of duals creates a lot of stability in wide heavy vehicles, it is not just about carrying the weight.

I like how you think: shed off that excess weight. You could do a single tire one ton rear axle swap, like from a Dana 70 or Chev 14 bolt or Ford 10.25". You can find those in 3.54 or 3.73 ratios pretty easy. It is harder to find the one ton rear ends in the higher 3.08 gears since the pinion offset has to be different to fit these "smaller" ring gears, and then you can't put in gears lower than a 3.54 in them.

You will probably only find a one ton rear end with 3.54 or 3.08 in a diesel. Another problem is the driveshaft and the yoke. You need to find a rear end that will take your yoke from your ex. rear end or has one the same size, or you have to modify the driveshaft.

A 3/4 ton rear end may work, but I think you will be too heavy for them.

good to know.

yeah, i have E range now.

hmm. sounds like probably more work than it is worth considering this is a recreational vehicle. probably i'll see if i can find a 3.54 or 3.73 since those are available as a factory option for the F series and i would expect the carrier to be the same even if the axle length is different.

i'll ask around on the ford enthusiasts forum, they seem to have a lot of knowledge when it comes to these sorts of things.

My '00 F250 has a 3:73 and a zf6 and single wheel, sterling 10.5 diff. The only difference between the 250 & the 350 SRW axle is a 3/4" axle spacer versius a 1/2" on the springs and a different rubber snubber per the parts list in my factory shop manuals as both models list the same axle part number. Excursions have a 4.10 and a 4.3 ditto for the 137" wheelbase pre'00 bump hood pickups

Local brick yard says they seem to work the same with a pallet of block in the back, the 250 sags a wee bit more at 1 ton probably why the spacer is different.

Drw rears are: full floating Dana 80 or 135 hints at 4.10 ratios, but aftermarket gear sets are common.

Could work but might be scary on I5, Ca 14 or US 395 most windy days but you could widen the trac by putting on the rims backwards with the offset facing outwards

I don't do the forums anymore since all the posts seem oriented towards smoke and hotrodding your 4wd mudder

The set with 5 ratios listed. The 4 speed obviously only has four (shows .71 twice, clearly it doesn't have two gears with identical ratios).

don't know if this is the most appropriate place for a build thread, but, i'm already here so...

i have a scangauge 3 on it's way (because there are 5 or 6 inputs i should keep an eye on at least until i have more confidence in the EGR cooler health)

spent the last weekend rebuilding the rear axle - new calipers/rotors/pads and axle seals - bearings were actually in really nice condition - i don't think they've been in there long. My mechanic friend explained that it is a full floating rear (and then explained to me why that is good :p) also replaced rotors and pads on the front axle, but, i had a lot of trouble bleeding and getting the system firm so i'm going to replace all of the rubber lines everywhere, the front calipers, and all new brake fluid - no reason to take any half measures with the brakes on something this heavy.

this weekend i plan on doing the line/caliper replacements. then i have some pinhole leaks in the fuel tank to deal with and i plan on going full synthetic with all oils and a water free heavy duty coolant (the biggest drawback is you have to change it out every 45,000 miles.. oh no! :D) the boiling/expansion point for it is MUCH higher than a water mix, so, it should do a great job of protecting my cooling system for.. well lets face it, it'll probably take me a DECADE to put 45k miles on this as a rec vehicle!

then comes the rear design - i want to boat tail this, and, i've read through the RV threads i've seen on here a number of times - the biggest questions i have is what i want to do inside the boat tail.

on one hand, i could have it be exterior only, and i think it'd make great exterior storage - there are all KINDS of things that could fit in there, including bikes, hoses, fuels, etc.

on the other, do i knock out a portion of the back wall and make it a master suite so that we have more room in the bus?

decisions, decisions :D

pretty sure i want to frame it out with an aluminum skeleton and composite fiberglass/xps sandwich panels. that should be really tough, well insulated, good sound dampening and long lasting. either way i go, that'll provide a secure storage area, or a nice "bedroom" and i have a good source for the framing both from an engineering standpoint and a fabrication standpoint because my mechanic friend builds these out for all kinds of things (as well as his son now for a different shop!)

then we can tackle the aero other places - like i intend to remove the mirrors and use cameras instead (which i actually already own and use on my current travel trailer) but leave the mounting studs in place in case i get in trouble and need to "fix it or ticket" - i can remount right on the side of the road if needed.

the space between the ... forehead bump? and the windshield looks like it could use some smoothing, as well as fiberglass blisters for the cameras.

we'll be doing away with the front bus door, so, can smooth that out and part will be used for external storage (the steps are going to get locking doors) and the upper portion turned into a window and/or storage.

i've been thinking and thinking about how to do a fixed awning that i could hide away inside the frame, but, ultimately i'm not sure that juice is worth the squeeze - considering just having lower mounts for the poles and taking it completely off when traveling - i wanna add underbelly storage anyhow, so i could slip it in there somewhere.

the grill/headlamps seem pretty smooth already, so i'm not sure i wanna do much there - but the front bumper is built out quite a bit from a pretty soft rubber mounted to an aluminum plate so i think that'll be a GREAT platform for an air dam or splitter?
(not mine, but same year/model/material)
https://cdn2.commercialtrucktrader.c...&blurValue=100

i also plan on trying to make the interior more energy efficient - probably going to insulate with a paint on vapor barrier and xps panel also considering an undercoating both for sound and protection - and because i want to add belly storage at least part of a underbelly pan - not real sure about mounting points though, because unlike the belly pan on orbywan's RV, mine floor is fiberglass and i kinda don't wanna run anything through it - and i don't have much by way of other things to attach to - just the frame rails.

where i put my tanks and underbelly storage, though, i'll probably mount something like Unistrut and threaded rod so that'll give me something solid.

just wanted to give an update since many of you have given a TON of input to me on this, so wanna keep you abreast of changes as they happen.

once it is home, i anticipate a lot more work completed, because it has it's own rear heat system i think i can get away with working on the interior in the winter, provided i can work up a "shore power" solution for it (it looks like the conditioning is actually AC powered with a large inverter behind the seat, because it has a load center that looks like a sub panel with normal breakers - but that doesn\'t mean it is.. :p

from this thread: HERE

i saw this recommendation on angles:

that seems like a very reasonable taper - but, i'm not sure about the chamfer - should it just be a straight 45-deg or would a curve between them be better? (or better enough for the effort vs the 45, which would be a lot more straight forward?)

the top to side corner(s) already have a chamfer that i could taper from possibly? would look better at any rate (assuming i don't do a bad job anyhow...)

Either way i plan on mocking something up with wood and sheeting - maybe even cardboard so i'll have some practice...

Disagree. 0-4 degree upsweep in the difusser.

In that area the constraint is not the airflow, it's the departure angle. IMHO side taper should be half the top taper.

45-degree chamfer or edge radius
 

The General Motors 'OPTIMUM' boat tail had all-radiused edges, however, was designed specifically for a trailer van with matching upper edge radii. GM used a radius equal to 7% of the trailer box height.
Since your bus already has the softened edges, it would make sense to integrate the tail into those.
GM's tail was 20-degrees downslope, 10-degrees plan-taper, and 10-degrees diffuser.
GM's tail length was 93% of the box height.
All edges, top, sides, rear, and bottom were softened with the same radius.
In Thomas Scott Briedenbach's US Patent # 8590961, he does the same thing. He used 12-degree upper, 12-degree sides, and 9-degree lower.
On my first trailer, I ran large Schedule-40 PVC pipe through a table saw and used the inner surface as tooling to create wet-layup FRP radii. Polyvinyl alcohol and 3-coats of carnauba wax made for a clean release.
It amplifies the fabrication man-hours, but kills edge vorticity, which can be a source of relatively high drag.

That is a great idea on the pvc, i was trying to figure out if i might do it with cut down rigid foam but felt like a lot of trial and error. I like that much better.

Got insurance and plate today, so now i just gotta finish the brake work and bring it home so i can have easy access for measurements.