Yukon Cornelius-SKO
Senior Member
Welcome, and sounds like the adventure is well afoot
Hi Leah!
Welcome. I am a newbie as of this month too! Haven't purchased a bus yet but just soaking up all the knowledge! Are you going to start an instagram or Youtube page? I'd love to watch your conversion if you are! I'm in SC so not too far away from VA! Hope it all goes well!!!
-RR
Sorry for the late return- didn't realize you'd replied!Haz.matt.1960 Hi there! That’s pretty cool! I’m quite curious how fast it’ll go. I’ll definitely get it turned up before I quit trucking and am able to be in the Skoolie full time.
Hey, it’s a used bus... driving it to this point, it seems like it has plenty of power. I’m not used to 2600 rpms at 6/mph tho. Maybe the tranny needs service to n will shift another gear. At least that’s what it sounds like it needs to do. Maybe it’s supposed to be like this. It’s got the 7.3 which is essentially the PowerStroke.
Brakes were working fine last night, I imagine they blew out all the rust accumulating around the valve?
Most likely your bus has an AT545 transmission. It's the most common one to find in that type of bus by a fair margin. It's a 4 speed with no lock-up so it's less efficient than basically any other transmission, and a lot of folks will dog on them pretty hard. I've got one in each of my 2 buses, they're not awesome but they're not junk either!
The AT545 has a gear ratio in top gear of 1:1. Most likely you've got a 4.78:1 rear axle (also very common, both my buses have them!) which adds up to a top speed in the neighborhood of 62mph. You've likely also noticed that spinning the motor at 2600rpm requires the throttle be pressed almost to the floor. The T444E can take it but your MPGs will suffer. I've found that my Thomas with the same drivetrain is happier in the 55-58mph range.
Thank you! I’m not sure the transmission on this or the gearing, but sure sounds like what you described. The truck I drive over the road, I don’t recall the gearing, but the rpms on it n any other truck I’ve driven the last 24 1/2 years, the rpms stay mostly between 1100-1600 n that’s pushing it hard on that top side. I’m definitely not used to it kinda screaming lol. I definitely want to find out what I can do short of spending a whole lot of money I don’t have to get the rpms down n speed up. Once the shop gets it running again, I’ll see if it does shift into 4 gears. It sounded like it had only done 3 but I wasn’t paying that close attention. I just wanted it to accelerate. I will say this tho, it feels like it’s got lots of power! Climbed the hills really well but then again there’s almost nothing in it either. Tow truck just got here...
Leah I've been messing with busses since the mid 70's. Sounds like you have jumped in with both feet. That is the way to do it. Welcome to the forum.
Sorry to hear about your difficulties. I know there area few members in that area, any details on what the problem might be?
Your rear axle ratio- that can be changed out for one that's suited for highway duty. School buses are generally geared fairly low. Not always. I've got one with interstate gearing. I got lucky.
Should be able to swap ratios for around a grand +/-
If your 545 transmission ever starts to go out don't buy another. Pay a few more bucks and swap it for a 643. That's go lockup and is generally all around stronger.
Sorry for the late return- didn't realize you'd replied!
Even more sorry about the inauspicious start, tho your philosophical take on it is refreshing. Many would wail, moan, and gnash their teeth over the unkind vagaries of fate.
(I'm their spokesman, btw [emoji849])
Hard to imagine the same mill moves that big girl, compared to my 8-window Shorty..!
Best of luck on the repairs, and may you have Happy Trails for the remainder of your trek!![]()
A little dirty now, but just wait until it’s done...
I feel for you and hope I never get the chance to take a picture like that!![]()