New here, 94 E350 7.3 IDI school bus. Hoping to swap axles for increased MPG's

Charles Moore

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Speaking for the community, we love pictures!:peelout

When you get time please post some either here or in the show us your ride thread. Personally, I'd like to know the details of your PV system and offer my help if it is needed. I've got a bit of experience, as we live off the grid pulling all of our electricity from the sun.

Nice way to live, I'd say! Here is a picture of my current PV system setup. I'd like to redo it so that (+) bus and the (-) bus are on opposite sides rather then right next to each other.

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Next step for the PV system is to add alternator charging for the house battery, and set it up so that when the house battery is fully charged the PV will charge the engine batteries. I should probably add in grid charging capabilities too..... but I'll be mostly boondocking so that's low on the priority list.

I do like 3.55 gears with the E4OD. I think your spring perch width is different from a truck however so you may have a hard time finding an axle.

Thanks for that. I'll make sure to measure that to help me look around for a replacement.



Here's a picture of the rig:

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No inside pictures yet since its a work in progress!!
 

dgr

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You can use any brand of glow plugs as long as they are motocraft/beru. Too many problems reported with other brands.

Clean that mess up then you can find the leak. Now that you have the drain cleared, hose it out and it'll run down the side of the transmission. Only a few places that can leak up there. Return lines, IP pump, feed from filter head. 1994 heads shouldn't have open coolant ports at the intake. That would show up on the front or back right at the glow plugs.

Why are you missing the CDR bolts?
 

Charles Moore

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You can use any brand of glow plugs as long as they are motocraft/beru. Too many problems reported with other brands.

Clean that mess up then you can find the leak. Now that you have the drain cleared, hose it out and it'll run down the side of the transmission. Only a few places that can leak up there. Return lines, IP pump, feed from filter head. 1994 heads shouldn't have open coolant ports at the intake. That would show up on the front or back right at the glow plugs.

Why are you missing the CDR bolts?

Ok thanks. I took the bolts out to take that thing out so I could have more space to clean everything up in there.

I've ordered my glow plugs up, so hopefully that helps out with the starting. Not looking forward to installing them though in the Mpls winter.....
 

david85

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That fuel leak doesn't look good. It's pooling right around the vent hose grommet for the CDR canister. Which means some could leak into the crank case.

The other thing to keep in mind is that diesels don't really like to sit. They'll start up just fine after a long slumber, but you need to run them pretty hard to get all their performance back. Also, winter tends to kill MPGs due to long warmup times and the switchover to winter diesel. At least, that's been my experience. I'd suggest getting a bigger sample size on your MPGs before making any drastic changes.

What kind of terrain are you driving in typically? If you're on the plains, then I'd say go for the 3.55s. If you're in the mountains, you might not gain much. Do you plan to ever tow?
 

compressionignitionrules

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that is a fullfloat wide only used in the E350 cutaway chassis 92 + all the E350 fullbody vans had a semifloat rear axle 92+ you can bolt in a semifloat but they are not as sturdy. If you are worried about your mileage upsize your tires to a 235/85/16. I ran them on my 2003 inplace of the 245/75/16. throws your speedo off a bit but most people now own a gps or have it on their phone....... you might only gain 1 or 2 mpg with a 3.55 swap, or if you like driving slower or lots of off pavement camping you might even lose a few mpg with a 4.10-3.55 swap.

if you ever want to haul with your camper the 4.10 woudl be better anyway.

and Welcome> nice camper/bus.
 

saburai

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Nice way to live, I'd say! Here is a picture of my current PV system setup. I'd like to redo it so that (+) bus and the (-) bus are on opposite sides rather then right next to each other.

You must be registered for see images attach


Next step for the PV system is to add alternator charging for the house battery, and set it up so that when the house battery is fully charged the PV will charge the engine batteries. I should probably add in grid charging capabilities too..... but I'll be mostly boondocking so that's low on the priority list.



Thanks for that. I'll make sure to measure that to help me look around for a replacement.



Here's a picture of the rig:

You must be registered for see images attach



No inside pictures yet since its a work in progress!!

Nice-looking rig! Are you running any sort of monitor for your solar system? I would highly recommend a bogart engineering trimetric. Just owning it and using it will teach you a lot about off grid charging and battery usage. Also in regard to grid charging, a combination inverter charger makes a lot of sense that's what we run in our off grid tiny home / RV. Happy to answer any questions that you might have...
 

Eli

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Forget replacing the rear - it's a hassle - and install a free-flowing exhaust and fix the fuel leaks!

Eli
 

Charles Moore

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The other thing to keep in mind is that diesels don't really like to sit. They'll start up just fine after a long slumber, but you need to run them pretty hard to get all their performance back. Also, winter tends to kill MPGs due to long warmup times and the switchover to winter diesel. At least, that's been my experience. I'd suggest getting a bigger sample size on your MPGs before making any drastic changes.

What kind of terrain are you driving in typically? If you're on the plains, then I'd say go for the 3.55s. If you're in the mountains, you might not gain much. Do you plan to ever tow?

Yeah this thing has been sitting a lot. I hadn't considered that would affect mileage at all . I'll be heading to warmer climates with it soon, so we'll see how things go w/o the winter fuel.

I'll keep the info on the rear diff in the back of my mind, but I think I'm going to hold off on swapping that out. I've been mostly in the plains up north recently, but I'll be over the place with this thing.

that is a fullfloat wide only used in the E350 cutaway chassis 92 + all the E350 fullbody vans had a semifloat rear axle 92+ you can bolt in a semifloat but they are not as sturdy. If you are worried about your mileage upsize your tires to a 235/85/16. I ran them on my 2003 inplace of the 245/75/16. throws your speedo off a bit but most people now own a gps or have it on their phone....... you might only gain 1 or 2 mpg with a 3.55 swap, or if you like driving slower or lots of off pavement camping you might even lose a few mpg with a 4.10-3.55 swap.

if you ever want to haul with your camper the 4.10 woudl be better anyway.

and Welcome> nice camper/bus.

I've got 235/85R16's on there already, but I'd love a 1-2 MPG increase! Most of my driving is on the highway with occasional jaunts on back country roads.
Nice-looking rig! Are you running any sort of monitor for your solar system? I would highly recommend a bogart engineering trimetric. Just owning it and using it will teach you a lot about off grid charging and battery usage. Also in regard to grid charging, a combination inverter charger makes a lot of sense that's what we run in our off grid tiny home / RV. Happy to answer any questions that you might have...
Yeah, I've got a Renogy Battery monitor. I set it up, but I haven't used it all yet. Do we'll see how it holds up.

Forget replacing the rear - it's a hassle - and install a free-flowing exhaust and fix the fuel leaks!

Yeah, the leaks are definitely first order of business! I hadn't thought of the exhaust much. I imagine that'd have to be custom made, and probably get pricy? What do you reckon that'd be good for as far MPG's go?

Thanks all!
 

IDIBRONCO

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I hadn't thought of the exhaust much. I imagine that'd have to be custom made, and probably get pricy? What do you reckon that'd be good for as far MPG's go?
I have no ideas on a possible MPG increase, but the cheapest way to go on the exhaust would be to replace your muffler with a freer flowing one. It wouldn't give you the full benefit of a complete exhaust system, but you'll get most of it and it will give you an idea if this is a step in the right direction.
 
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