Top speed of this bus?

[muddyrabbit]

Looking for our next project, and I'm considering this bus:

1999 Thomas International T444E Bus Wheel Chair Lift Air Brakes AT

We just did another cross country trip hauling motorcycles with our beastly Isuzu FSR flatbed, which is a great truck, but... The wife and I both agree it's time to do a bus project for our travels. We also both agree that the 63mph top speed of the Isuzu sucks, and we want to make sure we find something that can do highway speed.

So I'm hoping for some wisdom from the community on that bus. With the 4 speed will it do 70mph? If not, I imagine different gear set in the axle may be a solution?

[lornaschinske]

And how many feet do you think it would take to stop a fully converted bus at 70mph?

[muddyrabbit]

Probably less than the Isuzu FSR at 60 fully loaded.

Besides your idea of "fully converted" is a lot different from our plans.

Thanks for your input.

[Kubla]

it is going to have a top speed of 62, that is what they were goverened at when the chassis left the factory, I used to deliver them, same thing my 1997 international is set at, but you can get the top speed changed but you need to find out what rear end ratio is in it, mine has a 4.78 which gives me a theoretical top speed of 68 at 2700 rpm with 10R22.5 tires, but with the 10 % torque converter slip of my AT545 tranny 2700 rpm is just at 62.

since it has air brakes, it will have the same stopping distance as a straight truck of the same weight rating because it has the same brakes, as long as they are adjusted right

[Kubla]

one more thing, I bought my bus before measureing the width of the handicap lift, which is 30 inches, so my larger bikes will not fit on it, if you are planning to use it for that, measure first, also my back door is like 35 inches, and my Harley is 37 inches wide

[muddyrabbit]

Originally Posted by Kubla

it is going to have a top speed of 62, that is what they were goverened at when the chassis left the factory, I used to deliver them, same thing my 1997 international is set at, but you can get the top speed changed but you need to find out what rear end ratio is in it, mine has a 4.78 which gives me a theoretical top speed of 68 at 2700 rpm with 10R22.5 tires, but with the 10 % torque converter slip of my AT545 tranny 2700 rpm is just at 62.

since it has air brakes, it will have the same stopping distance as a straight truck of the same weight rating because it has the same brakes, as long as they are adjusted right

See, now that is the sort of useful info I was hoping for. Ya know, what you say about stopping distance just seems to make sense for some reason...

I'm also looking at an International with a 7 speed spicer manual trans.

[muddyrabbit]

Originally Posted by Kubla

one more thing, I bought my bus before measureing the width of the handicap lift, which is 30 inches, so my larger bikes will not fit on it, if you are planning to use it for that, measure first, also my back door is like 35 inches, and my Harley is 37 inches wide

Also good info, this has been on my mind. Our bikes are dual sports and adventure bikes, the largest is a Triumph Tiger 800XC. I think the bars are 34" wide but not sure.

[Kubla]

7 speed Spicer would be nice

[lornaschinske]

Originally Posted by muddyrabbit

Probably less than the Isuzu FSR at 60 fully loaded.

Besides your idea of "fully converted" is a lot different from our plans.

Thanks for your input.

No problem. But every time I read the "How fast can it go" questions I always remember the huge fiver being pulled by a rather large pickup truck and the look on the driver's face as the idiot tried to stop at a light on US76 (west side of Blairsville, GA). Major fail and a good thing there wasn't any vehicles crossing as he blew all the way thru the light. Managed to stop the thing after the fiver completely cleared the intersection. Good thing I had changed lanes. I don't know which was better... the look on the driver's face or the look on my daughter's face when she realized the RV wasn't going to stop in time and that if I hadn't of changed lanes, the Jeep would have been flattened. And yes, there were brakes on the fiver. Speed limit was 65mph.

[Kubla]

Trailer probably way overloaded and brakes not working right and most traffic lights on 65 mph roads have yellows that are too short or the moron just ignored it or the previous flashing warning light , stuff you learn in 13 years as a truck driver

[cowlitzcoach]

Most school buses of that vintage had top speeds in the 58-67 MPH range.

Even if you swapped out to faster gearing I doubt you would be able to go much faster than about 67 MPH.

The T444E is a great engine but it just doesn't have enough of what it takes to pull a bus through the air much faster.

With some engine modifications and hot rodding you might be able to up the HP and torque some. The reality is that in order to overcome the drag of the air pressure you are going to have to exponentially increase the HP to do that.

Most of those engines were in the 190-235 HP neighborhood. In order to cruise that bus at 70 MPH you would need at least 285 if not 300 HP.

When you get into those HP ranges you will start to have overheating issues. You will also start to exceed the design envelope of the transmission if it is an AT54X or 1000 series transmission.

We have one bus in our used inventory that was built with the MT653 transimission. It will cruise easily at 70+ MPH. But it has the DT466 285 HP engine as well.

If you really "need" to cruise in excess of 60 MPH you need to find a bus with more engine under the hood.

Good luck and happy trails.

[EastCoastCB]

Originally Posted by Kubla

7 speed Spicer would be nice

Really would be, especially on the highway.
I just don't enjoy driving in heavy traffic with a manual these days. Age is creeping up on me maybe.

[lornaschinske]

What flashing warning light? What yellow? The brakes on the trailer seemed to work just fine.... nice long skid marks. Probably similar to the one the driver and passenger had. I had rode thru town in front of them. No way was I going to stay in front of them going the speed they were doing. It was one of those "the truck can pull it" situations, the truck just couldn't stop it. I am very cautious of large loads behind me. Good thing or I wouldn't be posting this.

I may have run Hwy 76 at 85mph in my Jeep but no way would I do that in the Class C or the bus (which couldn't get up to that speed anyway).

[muddyrabbit]

Originally Posted by cowlitzcoach

Most school buses of that vintage had top speeds in the 58-67 MPH range.

Even if you swapped out to faster gearing I doubt you would be able to go much faster than about 67 MPH.

The T444E is a great engine but it just doesn't have enough of what it takes to pull a bus through the air much faster.

With some engine modifications and hot rodding you might be able to up the HP and torque some. The reality is that in order to overcome the drag of the air pressure you are going to have to exponentially increase the HP to do that.

Most of those engines were in the 190-235 HP neighborhood. In order to cruise that bus at 70 MPH you would need at least 285 if not 300 HP.

When you get into those HP ranges you will start to have overheating issues. You will also start to exceed the design envelope of the transmission if it is an AT54X or 1000 series transmission.

We have one bus in our used inventory that was built with the MT653 transimission. It will cruise easily at 70+ MPH. But it has the DT466 285 HP engine as well.

If you really "need" to cruise in excess of 60 MPH you need to find a bus with more engine under the hood.

Good luck and happy trails.

Can you send me your contact info? muddyrabbit@gmail.com

[muddyrabbit]

Originally Posted by lornaschinske

What flashing warning light? What yellow? The brakes on the trailer seemed to work just fine.... nice long skid marks. Probably similar to the one the driver and passenger had. I had rode thru town in front of them. No way was I going to stay in front of them going the speed they were doing. It was one of those "the truck can pull it" situations, the truck just couldn't stop it. I am very cautious of large loads behind me. Good thing or I wouldn't be posting this.

I may have run Hwy 76 at 85mph in my Jeep but no way would I do that in the Class C or the bus (which couldn't get up to that speed anyway).

So you had a bad encounter with a crappy driver, and based on that you are making a blanket statement that no one should drive a converted bus at 70mph on the highway, even though the same chassis, brakes, suspension, drivetrain, are used in many many commercial vehicles that weigh just as much as a converted skoolie and safely traverse the highways at 70+ MPH every day.

Seems legit, I think I'll start looking for a 55mph bus instead.

[jazty]

Originally Posted by muddyrabbit

Seems legit, I think I'll start looking for a 55mph bus instead.

I know you're being facetious and all, but I've gotta say that I love cruising between 55-60mph! It seems to be the sweet spot for quiet cruising and keeping money in my pocket, not spitting it out the exhaust. My bus is governed somewhere North of 65mph, but I have been seeing a 2 to 3mpg drop with that additional couple mph.

[muddyrabbit]

Originally Posted by jazty

I know you're being facetious and all, but I've gotta say that I love cruising between 55-60mph! It seems to be the sweet spot for quiet cruising and keeping money in my pocket, not spitting it out the exhaust. My bus is governed somewhere North of 65mph, but I have been seeing a 2 to 3mpg drop with that additional couple mph.

And for you that's what works, and better yet what you enjoy. It also highlights the different intended uses of a converted bus; for you the cruising in the bus was the end goal. For us though, the bus is a means to get the bikes and gear to the jumping off point for our adventures. We generally have 4 drivers to trade off, and when we do stuff like haul to Baja from Ohio to escape winter we have a 2500 mile drive, andabout a 2½ week vacation window. So 41.5 hours at 60mph vs. 35.5 hours at 70mph to get across the country is an important factor for us. Particularly in winter when days are short, that 6 hour difference can mean unloading bikes in the daylight instead of the dark, or getting to the end of the drive early enough to sleep for a night in a hotel and take showers before rolling out the next morning. I guess I just didn't appreciate the preachy attitude of the second post.

BTW, what is your bus?

[Booyah45828]

Lets all just calm down now. I don't think anybody means any offense here. Lorna presents some good points about speed, weight, and safety. But I can see occasions where one could use higher speed and still be safe.
Anyways, your top speed will depend on more then just the engine and trans. Rear gear and tire size plays a part too.
When I first picked up my bus, we did 65-70 mph on the interstate. That's with a 6.9 idi NA with an at545 and a 6.50 rear gear(180 Hp max, and that's being genserous). Idk how much power it takes to go that fast but I would think a t444e would have enough based off that experience.

[claydbal]

booyah, do you remember the rpm at that speed? also, do you know at what rpm/speed the trans shifted to fourth gear?

thanks

[Booyah45828]

No I couldn't tell you the specific rpm. Don't have a tach installed(looking though if you have or know of one available). I do know it was against the governor, or damn close to it because if we would hit a slight down hill you could hear the injection pump cutting fuel. I'm also thinking the injection pump was changed and it might have been changed to a 7.3 idi version because it smokes slightly at full throttle and seems to have the higher rpm governor springs as well.