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C.HARDY
Advanced Member

354 Posts

Posted - 02/23/2013 :  2:35:37 PM  Show Profile  Click to see C.HARDY's MSN Messenger address  Reply with Quote
I'm sure this is posted somewhere but I have a 1995 International with a T444E and a AT545. When you take off from a stop it seems like it shifts too soon into 3rd and then it will go back into 2nd and back and forth unless you floor board it. If you take off and just hold it to the floor it does fine and shifts great. We installed another transmission and it still doesnt shift right.....Is there any adjustment too how it shifts?

baptistbusman1
Senior Member

USA
74 Posts

Posted - 02/23/2013 :  3:04:36 PM  Show Profile  Reply with Quote
Did you replace the modulator on the side of the transmission? Also check your TPS on your throttle pedal.

I was formally Baptistbusman. However, I lost my password, and had not updated my email address.

Here is a link to my old posts. http://www.schoolbusfleet.com/forum/search.asp?mode=DoIt&MEMBER_ID=1846
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C.HARDY
Advanced Member

354 Posts

Posted - 02/25/2013 :  5:13:09 PM  Show Profile  Click to see C.HARDY's MSN Messenger address  Reply with Quote
I dont guess there is any adjustment on the electronis modulator is it? I never thought about the TPS, I will check that also. Thanks

"Hardybusman"
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dwight
Active Member

USA
42 Posts

Posted - 02/26/2013 :  10:24:07 PM  Show Profile  Reply with Quote
2/23/2013 What you have is a electronic drive by wire engine with a dumb-ass obsolete transmission that NEVER SHOULD HAVE BEEN INTRODUCED BY ALLISON in 1971. That's right, you have a transmission that was designed 50 years ago.''

There was a government law suit filed against General Motors Allison & Navistar in July,2000 but just before the trial date in late fall of 2001, it was settled out of court and all information pertaining to the lawsuit was ordered sealed by the court to keep the very negative transmission information out of public hands.

If your school bus didn't receive the throttle/modulator update and possible valve body spring modifications, that's your 1st problem. (Only those who yelled the loudest got them) The rest of the people were told, "IT MIGHT BE AN ADJUSTMENT PROBLEM". (When the transmissions fail you have your 2nd problem, the warranty has run out and it's no longer their problem.)

I would do the following test.
Put the shift lever in 1st gear and record the maximum mph or rpm attainable at full throttle. Do the same in 2nd gear, 3rd gear, and 4th gear.

Put the shift lever in 4th gear and record the maximum speeds or rpm each shift automatically occurs at full throttle.
If the 2-3 shift occurs to soon, you could drop the oil pan and tighten the 2-3 shift spring. (Each notch represents a 50 rpm change)

You may first want to contact a Allison service manager at a Detroit Diesel-Allison business with your full throttle data to help decide your next action.
Feel free to contact me by e-mail.

20 SCHOOL BUS FLEET OWNER/OPERATOR (Retired)
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