What's the best engine trans combo?

[davido-SKO]

If you were looking for a donor with diesel and auto, what would you get? The most reliable, gets the best mileage, makes the best power (maybe contradictory), etc.

I lean towards a 5.9/AT545, but that's only because I'm somewhat familiar with those two brands. I know nothing of Cats, Detriots, Internationals, etc.

 

[the_experience03]

I don't know that I would say it's the best by any means, but I have ZERO complaints about my 6.6 and AT545. I think a 5.9 might be better just because of the commonality thanks to Dodge. The holy grail seems to be a DT466 and MT643.

If you're looking to swap I think a 6BT out of a Dodge is going to be your best bet. It's up to you to find the tranny then. If you could find a 5.9 backed by either an NV4500 or an NV5600 ($$$) you would REALLY be my envy and I think both are rated plenty high enough load-wise for use in a skoolie.

 

[lapeer20m]

i am a convert when it comes to the 5.9. I'd say that the 5.9 cummins motor and a mt643 or even better a 10 speed manual would be the way to go.

the advantage of the 10 speed would be that you could put a rear end that was so conservative the engine couldn't even pull the vehicle down the road in high gear. You could use high gear while going downhill for added speed to help you get up the other side. That's what i would like to do.

 

[davido-SKO]

Cool. Why would you say that DT466 and MT643 is the holy grail? (I know nothing about this stuff)

 

[the_experience03]

The DT466 is a big engine. It is capable of producing incredible power numbers so in a skoolie setting where it is detuned a bit you will see an incredible amount of life. It also has that capability of making all that power. They have been in use since about the time Jesus roamed the Earth so finding parts and competent mechanics for them is not hard.

The MT643 is about the best automatic transmission you're going to find for a skoolie. They are rated for far greater weights than we will ever see. They also have a lockup torque converter in third and fourth gear leading to far greater mileage and speed potential than an AT545. In the coming years I think we will start to see more skoolies with the MD3060, 2000 Series, etc. These are even better transmissions as they have more gears and electronics to control them, but will be more expensive to maintain. As of right now they are found in buses that tend to be too expensive to be seen on the secondhand market.

 

[Jarlaxle]

Holy Grail: DT466 with either a Spicer 5-speed or an Eaton-Fuller Synchro-6 manual transmission.

 

[Abbott-SKO]

I like this thread.

 

[lapeer20m]

the engine is a ford/new holland 6.6 liter brazilian 6 cylinder diesel. I think they all came with turbo, some with aftercoolers.

@ 170 hp you probably don't have the intercooler. It's a bulletproof motor, but a bit shy on power. However, you can turn up the hp for free just by turning a screw.

I"m not a trans expert, but it looks like an allison automatic. Most likely an AT545 although i do not know the physical differences in appearance between that and the MT643.

I had that motor and an at545 trans in a 72 pass bus with 5.56 rear end. top speed was about 57 mph and hill climbing was beyond painful! However turning up the govenor and the fuel delivery rate i'm sure would help tremendously. Mileage was always good for me. About 8.5 mpg all the time. Had one or two occasions over 10 mpg.

 

[the_experience03]

Just the opposite, my friend. I know, it's not intuitive, but the higher the ratio numerically the lower the gear ratio is considered.

For example...a 1:1 ratio would simply mean that 1 turn of the driveshaft (and engine) would equate to 1 turn of the wheels. A 2:1 ratio would mean that it would take two turns of the driveshaft and engine to make the wheels go around once. You would have essentially doubled your available torque, but cost yourself half the top speed.

A 4.56 rear such as mine is going to have more jump off the line and a little more pulling power than an identical bus if it had a 4.11 ratio. My gear ratio is lower (numerically higher, remember). This comes at the expense of top speed and mileage.

By the way, that transmission is in fact an AT545.

As far as having to tromp on it to go anywhere...well...I think that's kind of par for the course with a bus. Once mine gets up to speed I can let off, it's not like a little Honda Civic where a gentle application of the throttle will get you a big variance in speed. I've heard many bus drivers say they have two "throttle" positions.....closed and wide open. There is no real middle ground.

If you're still really concerned about power I might suggest a psychiatric treatment that has worked for me. Spend a few years driving a stock geared 22re powered Toyota pickup with 31 inch or taller tires. Pretty soon that bus is going to feel like it scoots just fine.

 

[lapeer20m]

i had that motor in my old bus...not in the current one, and i'm planning to purchse mac's 60 foot articulating bus as soon as mine sells on ebay.

anyhow, back to the question at hand.

your gears should get you a little faster than my old bus, assuming the motor has the power to move the ol girl. With your gears, you would get slighly higher top end speed, and perhaps slightly better fuel economy at the cost of not quite as much pulling power for those hills.

I had an alluminum stick that fit nicely between the dash and the gas pedal to keep her all the way to the floor. the mechanic at the bus garage where i bought it said that the bus drivers had that thing to the floor it's entire life. It has about 300K miles when i got rid of it and for all i know is still running today.

these motors are knows for their reliablitly, but when they needs parts, they are very pricy, and can be a little difficult to find. the guy at autozone won't be able to find parts for a 6.6 liter 6 cylinder ford motor.

 

[the_experience03]

Don't worry, I was surprised at the size of the dipstick tube the first time I saw it. Even more surprising is the length of that thing (along with the one for the tranny). It expands inside the tube so you will have to turn that handle a couple of times to be able to pull the dipstick out.

You're right, diesel don't like air, but that's in the fuel system. Rest assured that you can pull that dipstick out without fear. Obviously for the most accurate measurement you're going to want to do it when the engine is warm, but not running.

My bus holds 20 quarts. Yep, that's 5 gallons of oil per change. You should try and find some documentation with yours to see what it takes. Otherwise I would just drain it and start adding oil, check with the dipstick, add oil, check with the dipstick, etc until you get to the full mark. It should also be noted that this thing isn't like your car. One quart is just a drop in the bucket.

I wrote a reply explaining how I figured my fuel mileage, but it seems to have been swallowed by the intarwebz so I will just tell you that my 6.6 gets 8 mpg and that's what I hear from all kinds of people with the same engine, regardless of configuration.

 

[the_experience03]

[drift]

This one is mine. It's a 1993 that I did a solid axle swap to a 1984 Toyota 8 inch front that was trussed and rebuilt. The front end uses 1993 FJ-40 rotors with the big 4 piston calipers off a 1994 V-6 powered Toyota 4wd and 1.5 inch billet All Pro Offroad wheel spacers on each side. The front is sprung on hybrid leaf springs made from the factory rear 51 inch leafs that have had 3 leafs added after removing the overload leaf. They are hung from a reworked Sky's Offroad hanger kit using widebody boomerang shackles. The shocks are Pro Comp ES9000's designed for an 8 inch lifted Chevy connected to F-250 shock towers while the steering is full crossover high steer using Stage 5 Sky arms and FJ-80 tie rod ends.

The rear is the stock wide track 8 inch with the LSPV wired wide open for better braking. The rear springs are 3 leaf 63 inch units off a 1988 2wd Chevy half ton using Sky Offroad hangers and 6 inch eye to eye unbraced shackles. I have 3 inch blocks to level it out with the front and u-bolt flips front and rear for clearance.

My current project is building a 305 for propane to replace the stock 22re/W56(D), and RF1A t-case. I already have a TH350 w/ a TransGo shift kit which is mated to an NP205 t-case that is awaiting the installation of a twin stick kit. Once I get all that junk in there I will worry about regearing to suit the new power and I will install a front locker when I get Longfield Super Axles for the front. The rear is open or welded (I switch back and forth) for now, but I will likely either adapt a Supra limited slip to it or get an automatic locker.

So far I'm happy with it. As you can see in the pictures of it on the lift it has INCREDIBLE yet USEFUL suspension travel. Obviously those last two pictures are on a lift with the suspension drooped WAY out and not at ride height. Ah projects....

[/drift]

 

[the_experience03]

There is a reason why I can rattle off every part on the thing and it makes surprisingly good sense once you think about it. So let's just say I need a left tie rod end. If I walk into the parts store and tell them I need a left threaded tie rod end for a 1993 Toyota they're going to give me one. Then I'm going to go home and realize that while the taper is the correct size the threaded shank is way too small to fit in my drag link. Now if I just walk in there and tell them I need a left threaded tie rod end for a 1996 FJ80 Landcruiser all will be well and it will all fit perfectly. I actually know a few people that have had to go to Valvoline to get their oil changed when they were up here (I don't change my own on trips either) and had to tell the guys to pretend their 1988 Toyota pickup is actually a 1988 Toyota Supra because they had swapped in the 7MGE 3.0 liter I-6 from one into the truck. Yep, it messes with people, but atleast you know you're getting the right parts.

Nothing on my truck is unique, believe it or not. Every part I swapped, including those from other vehicles, is tried and true low budget Toyota modifications that just plain work. About the only thing that is out of the ordinary is that the springs I used up front are from a 3rd Gen truck (like yours and mine) and are therefore 4 inches longer than the rears most guys use in front...but we made it work with some modifications. It really is amazing how brand loyal people are when in the end their rig is a menagerie of the best parts from every manufacturer.

And yes, the bus would probably win over the truck in both the standing quarter mile and top speed out on the salt flats.

 

[jdd-SKO]

looking for some feed back if possible i am looking around for my first skoolie and have found some internationals with dta 360 170 horse ive read they are a little under powered and if you turn them up the trany becomes the weak link theese ones have a five speed standard trany so finally my questions is the 360 that underpowered does the 5 speed make it better or worse if you turn them up will the 5 speed be ok im thinking yes and it has 4.44 rear axle ok comprimise for power and speed???? thanks for any help

 

[lapeer20m]

i have a dt360 and dont' think it's underpowered at all.....now that i turned it up. I would just about gnaw off my left arm to have a 5 speed manual trans.

the only downside to the 360 verses the 5.9 cummins is fuel economy. The 5.9 seems to be better on fuel.

 

[Dailybee23]

Does anyone think a 7.3 liter PowerStroke V8 Turbo Diesel (in a 1999 E450 Shuttle Bus) a good bus? how reliable is it compared to Cummins? Would you choose this type of bus for a conversion? I'm very new here, learning a lot as I go.

 

[Dailybee23]

7.3 liter PowerStroke V8 Turbo Diesel

Does anyone think a 7.3 liter PowerStroke V8 Turbo Diesel (in a 1999 E450 Shuttle Bus) a good bus? how reliable is it compared to Cummins? Would you choose this type of bus for a conversion? I'm very new here, learning a lot as I go.

also, didn't mean to reply to anybodies nor post this twice. I just don't know how to get rid of it now...

 

[PNW_Steve]

Holy Grail: DT466 with either a Spicer 5-speed or an Eaton-Fuller Synchro-6 manual transmission.

Yeah!

In a six window.


Don't forget about the 8.3 Cummins and the MD-3060. That combo should be high on the "holy trail" list.

 

[EastCoastCB]

Yeah!

In a six window.


Don't forget about the 8.3 Cummins and the MD-3060. That combo should be high on the "holy trail" list.

Cummins 8.3 and DT530 are both better "grail" engines.

Holy grail would mean something real special, though. Like maybe a full class 8 engine in a short conventional bus with manual and OD.

 

[TheArgobus]

Does anyone think a 7.3 liter PowerStroke V8 Turbo Diesel (in a 1999 E450 Shuttle Bus) a good bus? how reliable is it compared to Cummins? Would you choose this type of bus for a conversion? I'm very new here, learning a lot as I go.

Yes! One of my "highly desired" requirements when I was bus shopping was I really wanted an E450 with a 7.3L Powerstroke engine and automatic transmission. I ended up with a 1995 E350 with the 7.3L at 230,000 miles. Although it was older than I wanted, it turns out that it doesn't need to be Smog tested in CA (1998 and newer require smog testing). Everytime I bring it into the shop, at least one mechanic tells me how lucky I am I got that engine. There was another shortie there with the newer 6.0 L Powerstroke and they said they'd never even touch a vehicle with that engine, and that that shortie was in there all the time.


It's worth mentioning that I bought Argo for $2,500 and about a year later, had to rebuild the (non-stock) transmission ($3200 with a few upgrades) and the rear differential ($2000). Those are the only big ticket mx items I've had.



I've had Argo for two years now and haven't had any engine issues. If the bus is otherwise good (no rust, ideal size for you, etc) then I highly recommend getting it.