RedByrd - school bus ride with bad AT545

Рет қаралды 13,739

7 жыл бұрын

Last drive of my 2000 BlueBird school bus before I tear it down to replace the Allison AT545 transmission with a 1000. The 545 doesn't slip but it doesn't know what gear to be in.. shudders, slams , and sometimes wont downshift to first..

Пікірлер: 43

@kaiyoshi2243 6 жыл бұрын

Yeah a weak pump is my guess. Bet if you held the throttle at about a 1000 RPMs as you stopped it would drop into 1st like it should. But I've seen buses run like this for years before they finally gave up and died. Allison's are tough. Hope the upgrade went well.

@eldoradoboy 5 жыл бұрын

I drive that bus all over the country so I didnt want to risk it.. the 1000 has been running fantastic since early july 17 with no issues.. my MPG went way up too.. the AT545 in my other bus died in june of 2018, I changed it out with an MT643 since that one is an all mechanical bus.

@notsurehowloudthiscanget6103 4 жыл бұрын

I have a 1994 AM General M35A3 army truck that I bought a few months ago that was built with the AT545. I haven't driven it much yet being winter, but since I've bought it I noticed that the transmission seems to sound like it is shifting between gears when going from 2nd to 3rd, almost like it's shifting to 2.5 gear or something, but just for about 1.5 seconds. I guess another way to describe it is that the transmission is taking its time to shift to third, although it maintains smooth road speed acceleration. I run the motor up to about 2600 RPM and it shifts to 4th cleanly. From talking to another M35A3 owner, his truck's AT545 does the same thing, so is this kind of shifting to 3rd gear for the transmission normal for the AT545, or is there something I should be looking at? I'm running 10W-40 in the transmission, but haven't changed it yet. Nothing is overheating, and downshifting seems appropriate (downshifts when slowing to an intersection or up a hill and kicks to 1st when stopped). In one of my truck videos on my KZfaq channel you can actually hear it shifting into 3rd gear as it's going down the road. EDIT: I answered my own question. It turns out my truck is actually equipped with the AT1545, which has a locking torque converter. What sounds like another gear going from 2nd to 3rd is the torque converter actually locking up on 3rd gear. The AT1545 is unique to the M35A3 trucks.

@geekygeek22 4 жыл бұрын

How did the swap go? I have a 99 t444e with at 545 I'm wondering what the easiest option would be for a better trans, I was thinking a 643 or 1000, what would you recommend? (I'll be doing this mostly myself in my backyard)

@iwens1966 2 жыл бұрын

I'm a little late, but what did you end up switching to? I'm taking the 12 valve Cummins and AT545 out of a school bus and putting it in my 1985 30' RV. I will be replacing the AT545 with a 2008 Allison 2350 6 speed I picked up in Detroit, which is a heavier duty 1000. It's practically identical to the 1000, it just has a higher GVWR. 30,000 lbs vs the 19,500 lbs of the 1000. Same gear ratios and everything.

@divhandyman 7 жыл бұрын

Hey just wondering how the swap went were there many issues with the swap? I am in the process of trying to swap a AT545 to a 1000, but it is in a international t444e bus. Could you give any advice?

@eldoradoboy 7 жыл бұрын

hey!! i just finished a 950 mile ride with the new transmission. I would be glad to talk to you about all the things i did with the swap.. I too swapped into a 444E environment in a school bus.. there are several cinsiderations. contact my email at eldoradoboy@yahoo.com and we will exchange numbers and talk about it via phone, but its a beautiful thing once you get it in.. my 444E no longer runs hot.. my MPG's are much higher, the bus cruises along!

@jaggass 3 жыл бұрын

Are ZF or Voith gearboxes fairly popular in America?

@charlesrodriguez7984 2 жыл бұрын

Not really. Allison is more popular.

@Thairockshop 6 жыл бұрын

My '97 internationl 3600 bus is Longer and weighs in at 30,000-32,000 on the door. It has a 7.3 with 545. We drove it two hours and it didn't want to shift, didnt seem to have foutrh and would shudder occassionally,maybe between changing 2-3. What do you think? It felt like it maybe slipping as well, could nt tell when it did shift. Whats up> Modialtor, chaffed wire? I am having the starter relay above the tanny blow, and have a blown one to start it? Where is themost likely short? Finally, Will a 1000 transmission handle this weight bus? Or a 2000? What does they handle. I'dlike to tow a car behind it as well as highway and mountains. What tranny will handle 35,000lbs? A local diesel shop said they can just use an after market computer with the 1000 or 2000 tranny, But you went with original Equip. What do you think about aftermarket controls for a tranny upgrade? Thanks,

@cabdaddyb 5 жыл бұрын

iainw64 well bad news I have the same bus and after finding a Allison 2500 trans and was getting ready to put it in I made some calls to a few International/Allison dealers to see what I need to do as far as re programming the TCM and if I needed any parts I should replace while I had it out. And all three of the places I called told me that any Mt/electronic trans would not work with the 3 brain box controlled motors which was hard to believe but they all said as well it could be retrofitted and rigged up to maybe work but just thought I would tell you the bad news before you went and wasted your money on a transmission that you can’t use.

@PatrickBaptist 5 жыл бұрын

It doesn't weigh 30-32k, that is the gross weight rating.

@jaggass 2 жыл бұрын

Did it shift better going through the gears manually?

@eldoradoboy 2 жыл бұрын

sometimes.. other times it would not obey the gear... it always shifted forward / reverse / neutral fine, it just had issues picking its forward gear..

@jaggass 2 жыл бұрын

@@eldoradoboy Early automatics weren't great but have improved over the decades.

@jaggass 7 жыл бұрын

When did Allison stop making the AT545. Here in the UK it was in small buses till 2004.

@eldoradoboy 7 жыл бұрын

I think it was around 2002 or 2003, it wasnt uncommon here in the USA to see busses that had a chassis which was built a model year prior.. but the VIN is placed into service a year later so the bus could be a 2003 with a 2002 chassis on it, they used AT545's on full size busses up until the end.. (full size school busses).. I saw the AT545 on alot of busses with T-444E, CAT-3126, Cummins 5.9, and even some DT-466E. I have never seen a 545 mated to a later navistar like the VT-365 which came out in 2004. and of course Never was a 545 on higher spec engines like the 200+ HP DT-466's or cummins 8.3. those all had 643s in the early days then MD-3060s later on. 2000s and 3000s are all i see in school busses these days.. except now bluebird is offering a ford V-10 with an eaton automatic transmission optional..

@jaggass 7 жыл бұрын

They work pretty good in lightweight buses but bigger buses no. Alot of buses ive been on with AT545's like to jump in and out of gear or don't want to change gear at all. The 1000 conversion you have done is really good.

@jaggass 2 жыл бұрын

@@eldoradoboy Does 545 stand for maximum ft pounds of torque it can handle?

@jaggass 4 жыл бұрын

Did it jump in and out of gear alot?

@eldoradoboy 4 жыл бұрын

it actually seemed to just not know which gear to be in.. I suspect it had line pressure issues as many 545s do... much better since i put the 1000 in

@charlesrodriguez7984 2 жыл бұрын

@@eldoradoboy AT545 is a very old design it’s definitely a slow transmission.

@eldoradoboy 2 жыл бұрын

@@charlesrodriguez7984 and the Allison 1000 thats been in it 4 and a half years now is quite AWESOME.. works so much better!!!

@jaggass 2 жыл бұрын

@@eldoradoboy Allison automatics have come along way and the Allison 1000 is used in some buses here in the UK and has proven to be really good? Was it hard to maintain the original AT545? Some buses that used the AT545 here in the UK didn't last long and were replaced with rebuilt ones.

@jaggass 4 жыл бұрын

The engine must have screaming at 60mph +before the Allison 1000 upgrade.

@eldoradoboy 4 жыл бұрын

This bus was already a 70 MPH bus (70@2600RPM) before the new trans.. it is actually Over-geared now.. I need to gear the rear down from a 3.54 to a 4.10 to make 6th gear useful.. it RPMs a bit low in 6th now for what the 444E likes to run..

@jaggass 4 жыл бұрын

@@eldoradoboy So it's laboring a bit in 6th gear?

@eldoradoboy 4 жыл бұрын

@@jaggass yeah I only allow 6th gear to operate at light throttle and in conditions above 62 MPH.. with a 4.10 gear I could use 6th in more condition s and have 5th as a smaller-downshift. when i need a little RPM for a hill.. 4th is 1.00, 5th is 0.71, and 6th is 0.61. so you can see dropping from 5 to 4 is a HUGE downshift .. where if my 6th was operating in the 1800 RPM or so range at 65, a downshift to 5th would put me up in that 2100 or so range..

@h22eh6 3 жыл бұрын

What was your highway speed with the at545

@eldoradoboy 3 жыл бұрын

that bus ran 70 top speed.. it has 3.54 gears and 225/70R19.5 tires in it.. max engine RPN is 2600.. with the new transmission the sky is the limit esp now that I turned the motor power way up

@h22eh6 3 жыл бұрын

Christopher Abnett I’m getting a 98 international 4700 box truck with a dt466 automatic. A at545 is surely in it correct?

@eldoradoboy 3 жыл бұрын

@@h22eh6 in 98 there was 2 engines available in the 466 variant, a 466 mechanical and a 466E engine. the automatics available for the mechanical 466 were a MT643 and a AT545.. they may have had the MT653 also.. im not sure.. if it has ther 466E, the same above transmissions were offered along with a 6 speed MD3060.. the 3060 can be identified by the shift panel /lever having a digital display for 1 or 2 digits next to the pushbuttoms or lever.. getting the truck VIN and calling the IH dealer they can tell you what the truck was manufactured with engine and trans wise

@h22eh6 3 жыл бұрын

Christopher Abnett thank you so much. So if I have 99 dt466e with the at545 will I be able to maintain 65 mph? I’m hauling 3000lbs to 8000 lbs around metro Atlanta Georgia.

@eldoradoboy 3 жыл бұрын

@@h22eh6 depends on your tires and gears. top speed is all about gearing.. put a big cooler on that AT545 to keeo the heat out of it .. also depends on your engine HP rating.. mosrt of those 466E on AT545s are only 175HP rated.. ive seen them with 190 but much more and that trans wont like it..

@PatrickBaptist 5 жыл бұрын

Why a Allison 1000? That is for the little 4 wheelers..... I have a MD3060, I wouldn't want a 1000 series, the 3000s are 6 speeds and have retarders vs the 1000 series is just a 5 speed and no retarder....

@eldoradoboy 5 жыл бұрын

the 1000 is actually a 6 speed for years 2006+. and with 4th and 5th gen controls has excellent learning capabilities.. the 1000 and 2000 are very similar... 2000s have been used oin full sized school busses for many years.. 1000s have been installed in 6 wheelers for yeasrs as well, the GMC 5500,6500,7500 all ran 1000s. my 1000 was built for 500HP and 1000 Ft lbs of torque.. been runnin it since july of 17 no issues .. the MD3060 is a fantastic transmission but over-kill for a short 6 window bus with a T444E like mine.. I Tuned my engine up to 250 HP and still no issues.. retarder is a definite nice feature.. and one I could install on my 1000 if need-be.. my ECM supports it..

@BusMaster99 7 жыл бұрын

Poor thing.

@eldoradoboy 7 жыл бұрын

fortunately its getting a new lease on Life with an Allison 1000 (from CAC) upgrade..

@BusMaster99 7 жыл бұрын

Hooray!

@eldoradoboy 7 жыл бұрын

its been fantastic summer with it on the new transmission!! i drive it everywhere! even to starbucks!. finished a 3000 mile roadtrip a couple weeks ago. and soon will be on a 2500 mile trip.