Too many AT545's. Need help trying to find alternate transmissions.

[geminusprime]

So from what I've gathered here the AT545 is bottom of the barrel. Even though I'm looking at a non-40' bus, it'll still be in the 30' range and pushing the limits of an AT545.

Unfortunately, the VIN does not disclose what type of transmission is on a bus, and the majority of offers I've gone through not only don't list what transmission, but I've had several dealers that outright refused/can't to give me any more details other than "Automatic". Literally the only person I talked to that gave me specifics (even rear end ratios) was Union School District, NC bus lot.

This is kind of surprising, when buying cars (even used ones) the dealership generally knows the basic drivetrain details, and the Allisons have the model number right on the outside of the housing.


So, how does one find alternative methods of ruling out the AT545? I can't really afford to fly out to every potential offer to verify the transmission.

I know the AT545 is rated at 30,000lbs. Does that mean if I find a bus with a GVWR over 30,000 it will have a different transmission? For example, this bus I'm looking at has a GVWR of , but doesn't list the transmission. Could I assume it's at least not a 545?

Are there any specific models of buses, conventional or flatnose, that never had an option for an AT545?

I've found a few good options after pushing my budget up a thousand (currently $4500), but every single one has the AT545.

I'm not looking to have a full size bus or stay in mountain areas, but with the fuss over the AT545 I figure it's better to just get a different transmission to start out with instead of swapping it out later.

[brokedown]

The AT545 isn't optimal but it can be just fine. They made a million of them and they've travelled billions of miles. My first bus had one and I toured the country including all those pesky mountain areas, and my second bus has one too.

I wouldn't want to tow a toad with one but even then if you keep it cool it can give you a long successful life. It will always be at a disadvantage compared to a bus with a lock-up high gear but that's just life.

[Booyah45828]

Actually, I think the vin can give you that info, it's just not online. When ordering parts(for bluebird anyways) I call the dealer, and give them the body# and they can normally tell me everything about the bus. I would assume the vin would work the same way, you just have to figure out which dealer(bluebird, thomas, etc.) to call.

Most resellers won't give you that info because they don't have it. They'll sell it eventually without the info so in their eyes why bother.

As far as gvw goes, technically it's supposed to be used below 30K. But it's all based on what is spec'd by the district when ordering. The districts that bought busses with heavier axles wouldn't bat an eye to paying more for a trans upgrade as well.

I've got an at545, and have had no problems with it. Some do though, so I can understand your quest for a bus without one.

[EastCoastCB]

Originally Posted by brokedown

The AT545 isn't optimal but it can be just fine. They made a million of them and they've travelled billions of miles. My first bus had one and I toured the country including all those pesky mountain areas, and my second bus has one too.

I wouldn't want to tow a toad with one but even then if you keep it cool it can give you a long successful life. It will always be at a disadvantage compared to a bus with a lock-up high gear but that's just life.

It'll work until it doesn't. Like my bus' first 545.

[brokedown]

Everything just works until it doesn't! Keep the fluid full and the temps low and they can last a long time!

[Gdog 5651]

Absolutely true over the years I have dealt with many 545's one customer had one in an old Binder 2axle dump that climbed in and out of a quarry for 17 years extremely overloaded,truck plus 15 ton always, never had a trans repair the whole time it was maintained flawlessly.Another customer built a tool bus with a 3208 and a 545 it was way over gross and that combo lasted for many years with marginal maintenance, maintain it run an exceptional cooler and it will last a lot longer than the 545 haters on here say it will. Gene

[EastCoastCB]

My short bus is on its second 545 and its only got 64k miles and 3300 hours on the bus.
Chris just wore out his 545 by using it on the interstate.
Maybe if we start driving our buses through rock quarries the 545's will live longer?

[geminusprime]

Wonder how long a 545 would last doing this?

[o1marc]

Originally Posted by geminusprime

Wonder how long a 545 would last doing this?

Just after the film clip stopped.

[Johnny Mullet]

My AT545 has been good to me so far. I am preparing for a cross country trip in my bus with that tranny and it's the only thing that gives me butterflies in my stomach because of what I read here. It seems like these are pretty bulletproof transmissions, but if you get it hot it might just give up the ghost.

This tranny will not be a 75MPH Interstate cruiser, but most vehicles equipped with this tranny are governed or geared for optimum RPM and speed limited gearing to prevent overheating. I have no problem with a 55-65 MPH cruising speed in a 19000 lb vehicle.

[geminusprime]

Ever had issues with mountains? I'm not looking to explore only the mountains, but certainly want to do a cross country road trip and heard horror stories about the 545 and the mountains.

Also, if I end up pulling the trigger on the local bus with the 545, at the very least the bell housing on the 466 makes it possible to upgrade later down the line. I know it's not a favorable option, but at least it's cheaper that upgrading the engine.

[EastCoastCB]

Originally Posted by Johnny Mullet

My AT545 has been good to me so far. I am preparing for a cross country trip in my bus with that tranny and it's the only thing that gives me butterflies in my stomach because of what I read here. It seems like these are pretty bulletproof transmissions, but if you get it hot it might just give up the ghost.

This tranny will not be a 75MPH Interstate cruiser, but most vehicles equipped with this tranny are governed or geared for optimum RPM and speed limited gearing to prevent overheating. I have no problem with a 55-65 MPH cruising speed in a 19000 lb vehicle.

The main issue I had was that with the split rad design on my international I couldn't run it up to the speeds I like to go on the interstate/turnpike. Anything over 55 and it was slowly running up the temps till back to 55.
Give yourself and the bus plenty of time to get there and you'll likely be fine.
My most recent bus was bought assuming it had a 545. If that's the only downside I can shell out the $$ when its time to upgrade. 643's are cheap these days.

[EastCoastCB]

Originally Posted by geminusprime

Ever had issues with mountains? I'm not looking to explore only the mountains, but certainly want to do a cross country road trip and heard horror stories about the 545 and the mountains.

They have no engine braking. The steeper the terrain and the heavier they're loaded the more dangerous that becomes.

[cadillackid]

I blew up 2 (TWO) AT545s just driving on the interstate... granted I travel a lot in summer and was driving some mountains... Apps, smokies.. not like the rockies but still pulled some steep grades..



the red bus had a bad electric modulator that i didnt know about.. then replaced later but presumably the damage was done to the trans by then so it started to die a slow death. and i replaced it before it got un-driveable... it just forgot how to shift on a schedule... i'd be sittiong at a light and go to take off.. and it might be in 2.. then go "oh yeah I oughtta go into 1 now shouldnt I!".. other times it enjoyed making me spill my starbucks by going 2-3-2-3-2-3 really rapidly.. any transmission that makes me spill my starbucks or mountain dew is outta here baby!



the DEV bus i was just cruising around in columbus on a nice sunny HOT afternoon... hopped on the freeway and it went 1-2-3-N ? what? no 4? just N? forever N after that.. no more R or D or 3 or 2 or 1.. it just had ONE gear.. N... some AT that is.. at least it still had the gear N.. it coulda lost all its gears i guess..



I did get to hitch a ride home with that Hottie dude in the Peterbilt monster tow rig so all wasnt lost..





and now that bus has an MT-643..



-Christopher

[India2019Sada]

Originally Posted by EastCoastCB

They have no engine braking. The steeper the terrain and the heavier they're loaded the more dangerous that becomes.

Can you explain what that means, "no engine braking?"

[India2019Sada]

Hi everyone, this is a very interesting thread. I hope you can advise me a little more. I have already made a deposit on a 32 ft bus with the following specs, and I only just found out tonight that the AT545 doesn't have very good reviews. Can anyone tell me what their opinion of coupling the AT545 with the DT466e? I was wondering if the problems with the AT545 are due to the size of the bus and engine they are coupled with? The owner of the bus is generously letting me reconsider til tomorrow, I really don't want to make a mistake as it's my life savings and will still need to be converted to my home on wheels, plus needs to be transported from AZ to OR, don't want to make a single mistake, any advise is super welcome, thank you

Year: 2001
Make: International
Model: Conventional
Mileage: 105,000
Seating Capacity: 8 window
Fuel Type: Diesel
Engine Make: DT466e
Transmission: Allison 545
Brakes: Hydraulic

[geminusprime]

Originally Posted by India2019Sada

Can you explain what that means, "no engine braking?"

Engine braking is when you use the engine to slow the vehicle. Let go of the accelerator, the engine will try to reduce RPMs. When the axles are connected (locked) to the transmission, the engine will also slow down the axles, thus the vehicle.

The AT545 has a torque converter that does NOT lock. This means at no point is there a physical connection between the axles and transmission/engine.

[cadillackid]

if you own a modern car, go out and run it up to 65 or 70.. then left off the gas and use your car's ability to downshift... either with the pushbuttons on the steering wheel or shifting the shifter from D down to 3 or 2.. youll hear the engine rev and feel the car slow down very quickly qithout ever touching the brake pedal..



now go out on the same stretch of road same direction. and just shift to 'N'. and your car will just coast along slowing down at a much more gradual rate... (be sure to stop before shifting back to 'D')



in the mountains, as you are climbing a hill with your foot to tjhe floor, you are essentially storing energy.. in the form of going up the hill.. (what goes up must come down right?)..



now you reach the top and start going down... you of course dont have your foot on the gas. as you continue to gain speed you need to slow down.. (big grades like some of the appalachains and moreso cascades and rockies)/.. can have more energy as you gfo down than your brakes can handle..



big truckers downshift their trucks to lower gears to get a slowing effect without using brakes..



your brakes are abosrbing energy and turning it to heat.. the nore you use your brakes, the hitter they get... when you dont use them they cool off.. brakes in heavy vehicles on long steep downhills can easily get so hot that they fail to operate, burn-up, or fail...



this is where your engine comes in to play..



ever pumped up a bicycle tire by hand? when you push down on the bike pump handle it is hard to push!.. your engine does this same thing as it runs.. only 1000s of times. with 6 or 8 cylinders...



with a 'lockup' converter on your transmission you essentially are Locking your wheels to the engine.. making your wheels "pump" that engine.. the engine isnt burning any fuel.. and has a cooling system (radiator) to dispell any heat created...



you only need to use your brakes once in a while, so they stay cool enough that you are safe...



without that "lock", your wheels will spin but wont do much to "pump" the engine.. the engine will just kind of sit there.. not being any benefit to helping you slow down..



in town and on flat ground the AT545 is a fine transmission.. they were generally touted as one of the best stop N go transmissions built for their time.. and aftyer all thats what school busses did all day, year after year.. stop n go.. now we buy them and turn them into long road trip vehicles, wanting to trek all over the mountains, deserts, and the like..



many of the schools in the states with lots of hills / mountains bought busses with more stout transmissions .. esp for their field trip and sports busses.. many busses in the rural areas of colorado, utah and parts of washington state were big-engine , heavy transmission rigs.. Kentucky and PA also have a lot of these in the eastern states where mountains are an every day part of the bus routes..



Big semi truckers even install special devices on their engines.. called exhaust brakes or 'Jake' brakes.. thats the loud Wowowowowow!! sound you hear from truckers sometimes when they slow down quickly to stop or are going down hill... its an even more aggressive way to use engine resistance to slow their rigs down.



hope I didnt confuse anyone too much!
-Christopher

[PNW_Steve]

As mentioned above, you can call Bluebird with the body number and they can tell you all about the bus.

Same is true with International but using the VIN number.


Buses with desirable drive train are out there. It took me well over a year of near daily searching before I found mine. I still look from time to time and still see some good ones.

Good luck!

[Drew Bru]

Originally Posted by geminusprime

Ever had issues with mountains? I'm not looking to explore only the mountains, but certainly want to do a cross country road trip and heard horror stories about the 545 and the mountains.

Also, if I end up pulling the trigger on the local bus with the 545, at the very least the bell housing on the 466 makes it possible to upgrade later down the line. I know it's not a favorable option, but at least it's cheaper that upgrading the engine.

Johnbloem1974 had a whole thread about swapping a MT643 into his bus after his 545 crapped out. http://www.skoolie.net/forums/f37/cr...out-20640.html
He seems pleased as punch with the swap.