Mountains in the at545

[cadillackid]

N190 was one used pretty commonly in school busses

[turf]

if you can roll the chassis or lift the wheels off the ground you can get close.

tape a string to the drive line, turn the wheel one revolution. and count the wraps on of the string on the drive line.

~4 wraps of the string would probably be a be a 4:10
~4.5 wraps ....is probably the 4.78

i have a 4.78. with 11x22.5s, and i roll 67-68mph all day long at 2600rpm

[RolesvilleMarina]

Originally Posted by turf

if you can roll the chassis or lift the wheels off the ground you can get close.

tape a string to the drive line, turn the wheel one revolution. and count the wraps on of the string on the drive line.

~4 wraps of the string would probably be a be a 4:10
~4.5 wraps ....is probably the 4.78

i have a 4.78. with 11x22.5s, and i roll 67-68mph all day long at 2600rpm

We already know the ratio he currently has from the build sheet

[BrandinoBeatz]

thanks to this guy right here^

[RolesvilleMarina]

Like I said you have a few options if you want to keep the Vista.

the fact it has the DT408 is apparently a big plus with that P-pump etc. Seems to have a good rep. Others can chime in on that. I have the 7.3 and that's all I know anything about. my knowledge of IH comes from my years in the Scout World restoring those.

I was in your place 3 years ago as I told you when we met.

So, if you keep the bus and it looked clean what I saw, you have a few options

1. Keep it as is, drive slow. (I'm not a fan of this one)

2. Re-gear the rear end and keep the AT545 as it is solid when ran correctly, but is NOT a desired transmission for road trippin mountains or no... but it can be done with out dying or blowing it up yes.

3. Re-gear it, swap out to an MT643 (being air brakes you need less "parts) for this. It will also be easier being air brakes. This trans will give you the locking converter in 3-4 gear and will be helpful on fuel economy and engine braking ability down "mountains". However it will still be 1:1 final drive and so with your current rear end.

4. Put in an Alisson 2000. This will require more help from CadillacKid than myself as far as understanding how to make a 1994 harness work with the A-2000. As I stated in my post I "cheated" as I found out my Vista HAD the upgraded harness already, and the donor bus I bought had all the bits I needed for a somewhat easy swap. I continually admit I was stubborn and lucky on that one.


My thoughts:

Knowing what I know now, and having met you I would go for either #3 or even #4 if you can get help with the electronics

I went back and looked at my thread about MY swap (I hope you read it like I told you, a lot of your questions are already answered there, and by Chris as well)

My thread said the bus I found to do the swaps was as follows"

I've found an 2002 IH long bus with a 7.3 and a 2000 series trans
it has a 5.63 rear end
164 k miles "

So I drove that bus home.. and at around 2300 RPM with the 2000 and that trans I was driving at 62 ish I think.. I can't really remember but I was doing 65 ish for sure, and not at the TOP of my redline.. still higher than I wanted but she scooted



So if you can pull off a 2000 swap even with your rear end you can achieve a much better MPH/RPM trade off with the rear end you have now.

If the electronics are too much then maybe a re-gear and MT643 swap is better? Sure it will cost, but if you are crafty and think outside the box like I did you don't always have to have deep pockets

My swap I made $200 "on paper" when I was done..

However after $400 in misc fluids I think my trans swap cost me $200 and my time... as I sold the donor bus with working AT545

So if I was in your shoes and I wanted the Vista (I did, I love our vista and th unique ness of it.. ) I would do #3 or #4

and either way I would be looking to do it the same way I did, with a donor bus which doesn't have to be a vista, just an IH bus with air brakes and the proper trans etc..

again read my thread, read Cadillic Kid's redbyrd thread FIRST

and ask away..

I kinda stopped on the forums for a bit doing other stuff.. our vista runs great still and am uber happy with the swap.

And am glad to help with yours..

dave

[RolesvilleMarina]

Originally Posted by turf

if you can roll the chassis or lift the wheels off the ground you can get close.

tape a string to the drive line, turn the wheel one revolution. and count the wraps on of the string on the drive line.

~4 wraps of the string would probably be a be a 4:10
~4.5 wraps ....is probably the 4.78

i have a 4.78. with 11x22.5s, and i roll 67-68mph all day long at 2600rpm

My "numbers" are as follows after my swap

1999 Thomas Vista Bus 7 window
7.3
4.73 rear end (don't quote me, may be 4.78 I gotta go look)
255.70.22.5 Tires

( I have been told these are "low profile" for a school bus but I dunno **** about tires.. they are an odd duck number though) O


Pre-Swap

With the AT545 my motor was pegged at 2600 and I was gov'd at 55mph by the ECM (speed limiter)

Like most noobs went to IH dealer and had the limiter set to 80mph and called it sorted.. I would fly now right??

NOPE

Got on the highway home.. pegged at 2600 and got 57mph

the adventure began.. and many said to junk the Vista and get a "real bus" and start over.. I ignored and pushed on, as we REALLY love our vista. but like any other bus unless you get lucky the drive train sucks. They were meant to pickup kids slowly eh?


Post 2000 swap

Same tires
same rear end
Added .74 OD (overdrive) with the Alisson 5th gear (I do not have a 6th to unlock)

I can get her all the way up to 75+ and there feels like more (I am at 2400 rpm) But it is still a bus and it drives like a brick.

My goal though after finding out the correct "Sweet Spot" for MY ENGINE's RPMs I have achieved what I wanted..

I cruise with it set at 64mph and I am at 2050 revs. This is on flat ground, even towing the boat or jeep.

Up a hill I can maintain this speed until it becomes a "continuous climb" at which point she seems to climb at about 50mph easily on a steeper grade. Of course I have not hit any REAL mountains like out west stuff.. Fancy Gap however was a piece of cake


So pick what is comfortable for you, think outside the box, and remember gearing is a "give/take" as Cadillac explained above with the 10-spd analogy

[BrandinoBeatz]

yes thank you @rolesvilemarina, you have been a huge help and I appreciate all the info you've helped me with, I need a bus that is gonna get me miles and good to me, maybe I should have done more research and not rushed into the vista, I am not sure how hard it is to replace the trans in the vista but I also have no mechanical experience so im hoping I can figure this out..

[BrandinoBeatz]

my plan is to I guess switch the at545 with a mt643 and re gear once I can find the parts I need

[BrandinoBeatz]

if I just chawed the trans to a mt643 and didn't re gear would it be better for mountains?

[cadillackid]

Originally Posted by BrandinoBeatz

if I just chawed the trans to a mt643 and didn't re gear would it be better for mountains?

you would gain zero top speed however you gain in not making heat near as much.. you gain in dropping to 3rd gear you still have lockup and that gives you generally a bit better pulling power.. if you drop to second most likely your lockup will turn off and then its just like an extra big 545.. you'll make some heat.. though its a much beefier trans with better pump pressure and bigger converter so it still pulls good...



the reason for Overdrive (like the 1000/2000/3000 series) is that you have a wider range of what the trans has for ratios.. so it allows you to keep a lower ratio rear end which gives you better climbing capabilities.. along with a higher top speed that makes the bus more condusive to highway travel..



the MT643 is a BIG BEEFY unit.. but it does not have really much wider ratio than a 545.. and the top is still 1:1. (a 1:1 ratio means that your driveshaft is spinning the same speed as your engine)...


the swap from 545 to 643 in my DT360 bus was well worth it.. just in the fact I gained some MPGs (likely because im not slipping the converter and my engine fan doesnt have to run all the time in hot weather).. and I gained a bit of acceleration esp in 3rd gear after the lockup comes on.. again because by then my turbo is spooled and im not locked-in rather than wasting power on the torque converter..



for a DT360 its maxx RPM is 2800 factory.. my 643 shifts to 4th gear floored at 2400 which is a little early.. if im climbing a hill it can lug me down a bit and drop back to 3rd... all it would take woud be me dropping the pan and giving about 4 or 5 clicks on my 3-4th gear shift wheel and it would shift higher and eliminate that.. the trans was really set for a DT466 where 2400-2500 is where you want to shift..


I couldve put an electronic trans in that bus but I wanted to keep the mechanical bus mechanical... (it is somewhat of a classic in my book being that carpenter is out of business and mechanical DTs are long gone.. so I kind of kept it true to age / period..)...

[Jolly Roger bus 223]

better and more reliable than the 545 but still no speed demon up or down.
as has been said if you are in the mountains watch the big rigs and follow them.
they have turn out lanes and overshoot ramps for them as well as you if you overheat your brakes.
use them if you have to but try to stay off to one side or the other because if an 80,0000 pound monster is coming down and needs that breakaway ramp more than you do it wont have a choice especially if your not school bus yellow with flashing lights and all unloading kids where they dont belong.
me personally i will put my whatever in the ditch before hitting someone but then again i dont live in the mountain areas? i have driven through them and know what the runoff ramps are for.
as said.
what ever speed your combo is happy going up in then maintain that speed down.
and i really think that should apply to any mechanical tranny.
thats an opinion.

[cadillackid]

this and a couple other threads also highlight another important factor for those reading who haveny yet bought a bus.. take your time and BUY the bus you WANT with the drivetrain you want / need.. its MUCH EASIER and CHEAPER.. even if its a couple grand more.. you will have lots of hours and $$ into tranny swaps, rear end swaps, etc...I have access to nice paved spots to work in, a whole garage full of many tools (including scan tools).. along with the fact ive been building custom vehicles for years.. and trans swaps are still a lot of work..

[BrandinoBeatz]

Thankyou Cadillackid I appreciate the input and info!!, I like my bus and maybe this bus is gonna make me learn about internationals and diesels motors, I’m pretty dedicated to getting this bus ready for travel/mountains, as me and my girlfriend plan to travel around for a year or two here in the next year or so! I hear the tranny switch from a at 545 to a mt643 isn’t to hard? That is what a Freind @rolesvillemarina has told me, Now I have no mechanical experience but I am willing to learn!

[cadillackid]

In a DT408 the swap isn’t bad.. or you have a 466? I’m lost as to what engine you have.

The 408 and the 1994-up 466/466e use a 12 bolt flywheel. You’ll need a flexplate for the 643 for the engine.
You’ll remove the hub spacer and old flexplate, replace with shorter bolts and new flexplate..

If you have air brakes the swap is even easier.. if your 545 has a drum brake on the back life is much more difficult as that drum for a 643 is rate

[BrandinoBeatz]

Yeah I have a dt408! In the beginning the guy who sold me the bus said it was a dt466 cuz that’s what the church told him “supposibly” but when I got ahold of the build sheet it said dt408, seeing how they are very similar so I can see how he was confused!

Also I have air brakes in my bus (thankgod)

I’m not exactly sure what I’m gonna go with quite yet, I don’t want to get myself into something and get all lost and confused in the motor by swapimg the trans, unless I can find a full video step by step on exactly what to do idk if I’d be comfortable doing that plus it is most likely gonna be real pricey and gonna need a good amount of heavy duty tool to do such, so I might just keep the at545 and get big external trans coolers and just take it slow and easy (my girlfreind doesn’t like the idea of us goin fast in the bus anyway) …slow and steady wins that race both ways! !!!!

[BrandinoBeatz]

Just gonna be watching my temps and get probably get a transmission temp gauge to keep a better eye on it and just stop when I need to if she starts to get hot

[cadillackid]

I did the 643 in my dt360 and it was just heavy .. otherwise the job wasn’t bad.. the 545 ways about 375 lbs and the 643 close to 700. I used my engine hoist to pluck it off the bed of my pickup truck and put it on the Dooley I wheeled it under the bus with.. secured a couple 10000 on ratchet straps to the bus frame and lifted the trans up enough to wheel under my transmission jack. , secured the trans to the jack with chains and straps and then “kerchiunked it in place”… I used some headless bolts as guide dowels to guide the trans in and center it ….
My bus is a 3800 so I have easy access under the hood and in the doghouse.. no idea how a 3600 is to work in..

Measured for my driveshaft shortening .. dropped the whole set off at my favorite driveline shop for new u joints , carrier bearings, phasing and balancing.. shortening, ..

Reverse lights and neutral safety are same as 545, modulator is the same, I think I missed my shift linkage bracket a little , but the same cable and linkage and dash shifter for 545 and 643. My 545 was deep pan already so the dipstick and tube moved over as well to 643, cooler lines are bigger on 643 so I ram new ones. External filter is same. I also flushed the cooler lines fully since my 545 had nuked I wanted to make sure no debris was in the lines

[RolesvilleMarina]

Originally Posted by cadillackid

I did the 643 in my dt360 and it was just heavy .. otherwise the job wasn’t bad.. the 545 ways about 375 lbs and the 643 close to 700. I used my engine hoist to pluck it off the bed of my pickup truck and put it on the Dooley I wheeled it under the bus with.. secured a couple 10000 on ratchet straps to the bus frame and lifted the trans up enough to wheel under my transmission jack. , secured the trans to the jack with chains and straps and then “kerchiunked it in place”… I used some headless bolts as guide dowels to guide the trans in and center it ….
My bus is a 3800 so I have easy access under the hood and in the doghouse.. no idea how a 3600 is to work in..

Measured for my driveshaft shortening .. dropped the whole set off at my favorite driveline shop for new u joints , carrier bearings, phasing and balancing.. shortening, ..

Reverse lights and neutral safety are same as 545, modulator is the same, I think I missed my shift linkage bracket a little , but the same cable and linkage and dash shifter for 545 and 643. My 545 was deep pan already so the dipstick and tube moved over as well to 643, cooler lines are bigger on 643 so I ram new ones. External filter is same. I also flushed the cooler lines fully since my 545 had nuked I wanted to make sure no debris was in the lines

Yes other than the weight of the MT643 it's not a complicated swap.

The Vista doghouse makes it even easier to do the swap vs dog nose bus. When you remove the dog house the transmission is right there.

I used a chunk of round stock (metal) and laid it across the floor after removing the dog house. Then used ratchet straps attached to this pole and trans jack to separate it from the engine, and lower it down.

I used a chunk of plywood as a "sled" instead of a dolly to slide the transmissions around. I just drilled two holes one on each side at the top and put a chunk of scrap rope so I could pull it.

I used the large ratchet strap to pull this "sled" with trans on it down the length of the bus towards the rear until I could get it out from under bus (right before the rear wheel) as mine is a handicapped bus and lower up front.

As Chris said it's not rocket science. It is heavy

Yes I can help you do it here if you gather all the stuff and some friends to help with the heavy stuff.

Shortening the driveshaft is easy, you let a pro shop do it. you just need to get your measurements you are giving them correct. When I did my 2000 swap I thought I would have to do this, but was surprised that everything bolted up fine. This was in 2020 and everything is still cracking on splendid with the swap.

So again I would give you the same advice.

First decide if you want to keep the Vista. You can still clean it, run a better ad and prob sell it for a profit.

In our case we WANTED the vista. I LOVE the dog nose, I LOVE the turning radius. I did NOT have a big issue with too much heat from the engine position (I also insulated the doghouse, and dumped the AT545 lol)

We go to a lot of marina's and boat ramps.. we tow a boat. the vista front end is amazing for this, and much easier to drive (and I drive big trucks too)

But slow down some and make your choice. Sure I can help. Both Cadillac Kid and I have done this, alone, and we are NOT large blokes. You are young, and already taller and stronger than us so you have an advantage.

Chris is also right you can sell and look for the driveline you want... you will NOT find that in a vista lol. A few had MT643 but all but a few unicorns also have short rear ends.. especially NC and most eastern state buses.

But I love the Vista.

I like the short front and look, and it drives like a car
I like Unique and something few others have
I like I can work on the motor inside the bus.
I like the air brakes and of course the air door. Having an air door and no "bar" means you can easily put in a jump seat like I have and your girl can sit up front with ya

I like a lot about the Vista. But it is also a personal choice.

So being a mechanic it was easier to build the bus I wanted, by changing drivetrain, than to look for something that didn't exist or settle for something else. Again I wanted a T444E.


your DT408 motor is stellar, and your AT545 with a aftermarket cooler would be fine IF you drove it responsibly. You would be slow, but you would always make your destination. Just changing the old AF nasty fluid in the AT545 will net you at least 4-5mph min (it did mine in the donor bus)

You can also easily increase your HP on the DT408 (carefully, and follow write up/video from someone who has)

I have a link for the aftermarket trans cooler I am using on my 2000. I ran mine stand alone and am NOT using the cooling lines for the trans that originally go to the radiator. I will post it here, but if the forum doesn't allow amazon link message me I will send it

So yeah. you have to do two things right now is all.

1. Calm down, deep breath.. you're not in a race
2. Choose wisely. R&R a transmission is not THAT bad and can be done with simple hand tools.

If you choose to keep the Vista I would look into Re gearing and MT643, but I also would not be trying to do it "all in a weekend" I would look for a donor bus if I could, as then I can sell the donor bus with the At545 and a short rear and make my $ back and have the vista with what I wanted. Also look online and can buy parts A la carte as Cadillac does/did. Regardless how just look for the best deal.. it is possible you can re-sell your 5.38 for example.

Also the option of an Allison 2000 swap is still possible, but is more detailed and you would have to ask Cadillac about that with your older harness and DT408.. I know you do not have cruise control so that helps some

but regardless you are not "screwed " lol.. you can sell that bus right now for a profit, start over..

or go down the Vista path

Either way yeah I will help what I can.

Remember 80% of the buses, maybe more, are geared short AF like yours.. especially in NC. you are buying something designed to stop n go and turn it into a custom cruiser for your needs..

so this is part of the "Custom" part... but if you choose to follow through you would have something pretty special

It is 100% up to you

Here is the Cooler I use

https://www.amazon.com/Hayden-Automo...ustomerReviews

[Jolly Roger bus 223]

if you decide to change this at rolesvilles place and schedule it my son and i are only a few hours away with almost everything but a bus scan tool? we have an OBD 2 scanner.
dont have a tranny jack but do have an adapter i have made for one of mine into a tranny jack.
thats no fun by yourself without the proper stuff.
talking about getting hurt and wore out quick.

[RolesvilleMarina]

Originally Posted by Jolly Roger bus 223

if you decide to change this at rolesvilles place and schedule it my son and i are only a few hours away with almost everything but a bus scan tool? we have an OBD 2 scanner.
dont have a tranny jack but do have an adapter i have made for one of mine into a tranny jack.
thats no fun by yourself without the proper stuff.
talking about getting hurt and wore out quick.

That's awesome of you!

I live in Wake Forest.. top of N Raleigh basically..

When I did my swap I was alone and had the 7 window vista as well as the full sized donor side by side in the back yard.

we need some
1. scrap plywood and some rope
2. ratchet straps (big ones)
3. Trans jack.. I bought one at HF and then sold it after the job for the same price
4. the parts
5. labor help and simple hand tools.

If he goes MT643 he'll have to come back after the driveshaft is shortened but we can do that just him and I


I can do this again

I learned a lot.

HOWEVER!

CadillacKid paved the way on this stuff, credit deserved and given!

I wouldn't have attempted what I did without his guidance and a few others here at my local International Dealer (and some donuts)


So again we CAN do this if we can source the parts..

Is it worth it? Dunno, a question only BrandinoBeatz can answer.

For me personally I would as I love the Vista. He's got a great engine, and even an AT545 would be fine with additional cooling, an EGT gauge and Temp Gauge.

So like SOOOOOO many it's a rear end issue

BrandinoBeatz can pave the way showing a skoolies how to do a regear on the cheat side like I did my trans swap

But again, his bus. I like the Vista, and I like to build **** people say can't be done.. I like Unique stuff and the Vista ALWAYS turns heads with "thats sooo cute"

and I like IH.. everything else he is dealing with is simply trans and rear end..

not that hard.. just heavy..

unlike me and chris though He has the offer of PHYSICAL help if we do it here when it is cooler out but not sh*tty out

I also since doing the trans swap started a Dumpster biz here with a partner.. so I have a "hook truck" here and I can lift 10 ton with it.. I often use it as a "personal crane" around the yard doing my bollocks

dave