The Diesel Stop banner

1 - 20 of 22 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
My name is Logan. I'm in the process of converting a 99 IH 3800 T444e School Bus into a highway cruiser to take my 6 kids (our oldest has severe autism and is non-verbal) to see the country. The bus was inspected up until the 2011-2012 school year. I have taken it to my local IH dealer and they have raised the governor to 85 (from 58) and enabled the cruise control. Our goal is to go see grandma in Washington state in the spring. After reading a lot of posts here, I'm curious to the reliability of the T444e. The odometer says it has 232,000 miles and about 10,000ish hours. I'm kinda new to the having a Diesel. We've taken a few 3-4 hour trips with no issues. It did overheat on me once when it was full of furniture and pulling a trailer at high way speeds for about 2 hours straight. What kind of preventative maintenance should I look into? And what type of modifications can I do for our trip in the spring? I'm looking at getting a EGT, Transmission and Boost gauge to keep an eye on things and maybe adding a Transmission Cooler and Fan. Last thing I want to do is be stuck with my kiddos in the middle of no where.
 

·
Registered
Joined
·
823 Posts
This first question I have is what kind of transmission does it have?

The reason I ask is that if it lacks a proper overdrive, highway driving will put your engine speed well above 2,000 RPM, which is above the "sweet spot" for this engine, and could cost you a lot of $$$ in fuel and repairs.

What's the GVWR of the chassis? If the transmission is a Allison 3000 series, I'd say you're good to go. If it's a 1000, 2000, or a AT545, it might need some attention. Worst case would be the AT545, as it lacks an overdrive, and does not have a lockup torque converter.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #3
Thank for the response! The GVWR says 25500. Originally it was a 39 passenger but could also accommodate 6 wheel chairs. There's 10 windows on the driver side. I'm pretty sure it is the 545 transmission. On a drive today, I noticed it was at 2700 rpm at 65 mph. I don't think I felt any TC lockup :-(
The vin # is 1HVBBABM6XH227935 if that helps anyone. Maybe we can figure out what rear it has too.
It's okay with me to swap transmissions or gearing if that's what I need to save up for. Unfortunately the exterior is repainted and the interior is almost done so I really would like to avoid purchasing another bus and starting over.
 

·
Registered
Joined
·
823 Posts
The AT-545 was Allison's cheapest transmission. Not having a lock up torque converter means that the more load you put on it, the more heat it will build up. And it can reach a certain point where torque converter slippage will limit the amount of torque that you pass from engine to driveshaft.

I learned about it while trying to retrofit a PTO generator to an International 4700LP with a T444E and AT-545 about 16 years ago. The PTO outlet is driven by the torque converter (turbine). The amount of slippage limited our generator output to about 12,500 watts. Anymore load than that would cause the slippage to generate more heat than the transmission cooler could handle.

If we'd had a lock-up torque converter, or a newer "world series" transmission, then we could have gone up to 25,000 watts or maybe more.

The new "world series" transmissions have the PTO driven by the flywheel, not the torque converter. I know that doesn't matter to you, I'm just sharing it to illustrate the differences in the transmissions.

Honestly, 2,700 RPM at 65 MPH is pretty high. Keeping your bus at that speed for sustained periods of time won't be good for it. You could find a Allison MD-3060, MD-3560, or any other 3000 series to replace it. Granted, it should come from a chassis where it was already mated to a T444E, to make installation simpler. Otherwise, you'll need an Allison Guru who knows how to get the wiring and control modules properly communicating.

The 3000 series transmission has 6 speeds, the AT-545 has only 4. In both models, 4th gear is a 1:1 ratio, or direct drive. In the 3000 series, 5th gear is a 0.75:1 overdrive, that would lower your engine RPM's at 65 MPH to 2,025. 6th gear is a 0.65:1 overdrive, that would lower your engine RPM's at 65 MPH to 1,755.

Otherwise, I'd stick to keeping the bus at 55 MPH or slower for long trips.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #5
Awesome! Thank you so much for the info! I thought about changing the gears in the rear but I think doing a 6 speed Sounds like a better idea. Does my 7.3 have enough torque or horsepower for the over drives? It's rated for 190 on the tag on the engine. Other than the re-flash the IH shop did, it's still in stock form. I found one controller from TS performance. Is this something I should invest in with the engine having 230k miles? What other performance or longevity stuff should I do to the engine? Intake? Straight pipe? I guess there's not a lot of performance stuff for my setup.
When I bus is done, it's actually going to be a lot lighter than with all the seats in it. We can't do hotel rooms so it's mainly for travel and sleep. No plumbing will be done. One RV pull out couch. 2 dinettes that convert to beds and 8 conversion van captains chairs. Basically just a big van :)
 

·
Registered
Joined
·
823 Posts
I don't think a TS chip will work on the T444E. Sure, the hardware on a T444E and Ford 7.3 Power Stroke are almost identical, but the Engine Control Unit for each are vastly different. The computers do not speak the same language. The difference between a International computer and a Ford computer is like the difference between a PC and a Mac. As far as writing special tuning programs for a Navistar ECU, I got no suggestions. I have no idea who does that.

I think the stock T444E should have adequate torque for the overdrives, provided you're on flat land. When you hit hills, that would be another story. In my opinion, the MD3560 or 3500 series transmission would be better. It's a wide ratio transmission, meaning the lower gears (1st, 2nd, and maybe 3rd) are geared really low, giving you better take off. The trade off is that the engine revs up a little more before shifting to the next gear. But this only applies to the lower gears, not the higher ones.
 

·
Registered
Joined
·
3,778 Posts
A front air dam will divert more air through the radiator and less air underneath it, and will significantly reduce aerodynamic drag (and noise) if it's wide enough to divert air around the front tires.

Side skirts and rear-tire air dams won't be as effective as a front air dam, but will also reduce drag. (and noise)

A radiator-fan clutch, hydraulic fan drive or electric fan will eliminate a lot of wasted horsepower (and noise) turning the fan when it's not needed. Chances are, a school bus is configured for city driving (and least-bid purchasing) and has just a plain 'ol direct drive fan.

Doing all three will make the bus easier to push down the highway and be like getting 15 or 20 extra horsepower (or 5 extra mi/hr) for free.



Painting the roof with bright aluminum paint will reduce solar gain and reduce the air conditioner's power consumption, the air conditioner's effectiveness and the indoor temperature while parked. Aluminum paint will also reduce the amount of heat the roof loses on cold, clear nights.
Aluminum paint is significantly more effective than white paint. White paint, surprisingly, is not much more effective than other light colors. (much of the sun's energy is in the UV spectrum, which humans can't see)


... Not having a lock-up torque converter means ... more heat ...
The flip side: After installing a lock-up torque converter, increasing the transmission cooler capacity is probably unnecessary.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #8 (Edited)
Well, this is great. I've called around a bit this morning and no one around me wants to tackle a 4 speed to 5 or 6 speed swap..... I quit telling them it was a bus and just started saying it was an International with a 7.3 and a AT545 transmission.... as soon as "school bus" came out of my mouth, I got shut down. So I guess I'll look for an Allison Dealer?
Wouldn't a "highway" transmission from a tow truck, a roll back, or a straight truck work? As long as it had a 7.3? What about a Ford truck transmission with an independent controller? Gear Vendors doesn't offer anything for this transmission either.
Here's a picture of it. :)
 

·
Registered
Joined
·
823 Posts
as soon as "school bus" came out of my mouth, I got shut down.
Yeah, when you say it's a school bus, it implies that children will be riding it to school. If the mechanics altered the vehicle with a 6-speed that would allow it to run 100 MPH, they certainly wouldn't be doing anyone a favor.

The regulations for school bus design and construction are pretty in depth. I work as a career firefighter, and on occasion we get to train on cutting school buses open in preparation for a bad accident. I can tell you first hand, school buses are tough.
 

·
Registered
Joined
·
3,778 Posts
... as soon as "school bus" came out of my mouth, I got shut down. ...
I doubt it has anything to do with potential product liability. There are a few other possibilities:

First, maybe International never offered the 6-speed lockup in a school bus, figuring that they needed to do everything possible to hold down the purchase price to sell any buses. If they never offered if as a factory option, nobody ever worked out all the installation details.

And maybe the 6-speed lockup was never offered in any platform that model year and there's no combination of engine controller and transmission controller that speak the same language. Or more likely, the information available at the parts counter is insufficient to confirm or deny whether that combination can work.


Last, if memory and the rumor mill serve me faithfully:
Knowing that school buses were almost always purchased on a least-bid basis, then maintained almost for eternity, International adjusted their marketing & pricing to lower the cost of buses and raise the cost of replacement parts. This they did with two sets of part numbers -- one for trucks and a different one for buses, with greatly marked-up prices on otherwise-identical bus parts. As difficult as it always is to get the right parts for the right application, the possibility of two sets of books might spook your friendly local IH parts counter person into not even attempting this quest.

I first heard this rumor in the 1970s. I don't know if was still in effect by 1999, if it continued after International Harvester became Navistar, International Truck, International Engine and/or International Truck&Engine; or if it ever was.

Still, it could never hurt to refer to your vehicle only as, say, a "1999 IH 3400 with a T444e, 22,000-pound GVWR and 180-inch wheelbase".


Finally, contact the EPA. This proposed transmission swap will significantly reduce the vehicle's CO₂ emissions. Ohio might be the 47th-most-progressive state in the union and Nerk might not be a designated non-attainment area, but the EPA might have some expertise within their Diesel School Bus Retrofit Program and the project might be eligible for a tax credit.
 

·
Registered
Joined
·
3,553 Posts
Here is a link to your engine, International T444E Specs
Basically it's the same as the Powerstroke 7.3 in 1999, but the bus engine was governed at 2600 RPM, but you already said you had them change that and a ECU reflash. That will change the HP and torque curve. I have the SP Performance on my 99 PSD, it will give you a little more HP if needed when climbing hills, which I'm sure you will be doing on your trip. You must have these gauges for that TSP, EGT, Trans oil temp, and coolant temp. A boost gauge would be nice but not neccessary. The only Ford trans. that would fit with OD would be the 4R100, pretty sure of that but not certain, but it does have lockup and OD. Possible would need a stand alone trans. controller. If that is so, it should handle the weight OK. Don't know what turbo Navistar used, but possible it could be updated. With a 4R100, the drive shaft would have to be changed. To classify the Bus as an RV, I hope you know what it takes, and then be inspected to change the registration. I did a School Bus way back in the late 60's and a GM Grayhound Bus in the 90's. When you have the conversion all completed, get it weighed, IIRC my School Bus weighed in at around 14,000, it was a 42 passenger. My five kids, Wife and I had a lot of fun in it, even climbed Mt.Rushmore in it. It wasn't a Diesel, I had put a Ford 390 engine in it and a two speed rear. I'll see if I can get more info on tranny change on a different Diesel forum for you.
EDIT: You will definatly need a trans Aux cooler. School Busses are all Go and Stop short distances.
EDIT 2: Call this number, maybe they can tell U if there is an Allison with OD that will fit,they are in Taylor MI, that's close to U. Call 1-800-252-5ATD. You'll get the right transmission for your job.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #12
Okey doe-key, I'm back. I had given up on finding a transmission and started looking for a rear end. My bus has 4.73 gears. I haven't done anything with the bus lately but today I got a line on a 2000 International with a DT466 and a 5 speed Allison automatic. The VIN# on it is 1HVBBAAN31H407679. Could this 5 speed bolt up to my T444e? Anyone know what the rear ratio might be on this new bus? How about computer compatibilities? Thanks in advance!
 

·
Registered
Joined
·
895 Posts
I would think you would be much better off keeping the DT466 mated to the 5 speed Allison, rather than pull them apart and try and retrofit that trans to your T444e.

Who is going to engineer the electronics control the retrofitted trans with the engines ECU? Who is going to write the TCC lock up strategy, and figure out what inputs from the ECU are needed to keep the trans from stalling or disintegrating?

Changing axles and/or swapping gears is one thing. Adapting electronically controlled engines to electronically controlled automatic transmissions is something else entirely.

It seems to me you would be better off picking an engine/tranny combination where all that engineering and computer coordination is already professionally worked out and proven in the field. I doubt any mechanic who is perfectly capable of swapping transmissions would at the same time be interested in electrically engineering differences in SAE network protocols and control engineering driveability.

The DT466 will produce more torque than a T444e. If you already have the engine and transmission together, you might consider keeping them together.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #14
Well, Crap..... looks like I'm building another bus. I went to look at the 2000 (Actually 2001) with the 466 and 5 speed automatic and ended up driving it home..... It has air ride, air seat, air brakes, the wheel chair lift is in the front instead of the back...... Just an all around better platform to start with. She's governed at 61mph but instead of 2800 rpm it's around 1900-2000 rpm...... Once I have the governor adjusted and other parameters changed; she should cruise around 70 nicely. :)

Thanks everyone for all your help and information!!!

 

·
Registered
Joined
·
823 Posts
It the transmission is an Allison 3000, 3060, 3500, or 3560, it should have six speeds in the transmission. If and when you get it reprogrammed, ask them to engaged the 6th gear.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #17
I'm pretty sure it's a 2000 series. If I'm not mistaken I think the other with the 6 speed capability we're push button operated. This one still has the good ol T-handle shift lever. I will definitely check though. :)
 

·
Registered
Joined
·
9 Posts
Discussion Starter #18
Hey guys, just checking in. The new bus is great- it currently has 5.38 gears. As luck would have, I ran across a 4.44 rear ring and pinion that I'm having installed right now. We are switching from 40 tooth axles to 36 tooth- don't think that should be an issue. Excited to get it back and see what type of difference there is. It still has the original bus interior- still debating how I'm gonna do the new layout. My old bus is for sale if anyone wants it. :)
Party Bus!!
 

·
Registered
Joined
·
1 Posts
My name is Logan. I'm in the process of converting a 99 IH 3800 T444e School Bus into a highway cruiser to take my 6 kids (our oldest has severe autism and is non-verbal) to see the country. The bus was inspected up until the 2011-2012 school year. I have taken it to my local IH dealer and they have raised the governor to 85 (from 58) and enabled the cruise control. Our goal is to go see grandma in Washington state in the spring. After reading a lot of posts here, I'm curious to the reliability of the T444e. The odometer says it has 232,000 miles and about 10,000ish hours. I'm kinda new to the having a Diesel. We've taken a few 3-4 hour trips with no issues. It did overheat on me once when it was full of furniture and pulling a trailer at high way speeds for about 2 hours straight. What kind of preventative maintenance should I look into? And what type of modifications can I do for our trip in the spring? I'm looking at getting a EGT, Transmission and Boost gauge to keep an eye on things and maybe adding a Transmission Cooler and Fan. Last thing I want to do is be stuck with my kiddos in the middle of no where.
Hoping you check back on this thread once in a while. Will have a similar '99 IC short bus with a DT444E and some brand of Allison Transmission, possibly a 2000. Would like to put 4WD under it New axles, suspension, driveshafts, and transfer case. Hopefully can borrow a lot of it from old military gear. The responses here are very helpful and will be my reference once I get into it.
 

·
Registered
Joined
·
6 Posts
Jpresnell

Hi Loganbus You can use a Allison MT643 it is a 4 speed lock up toque converter with no computer. It will go behind the T444e. I also Changed my rear gear form A 373 to a 354. 99SD Memeber #40608 Posed so time back a list of all the parts needed to make it work and a draw from Allison AS04-317. I also would like to get a hold of him.
 
1 - 20 of 22 Posts
Top