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Jeremy
Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 2994
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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How are you i have an allison at-545rm it is not up shifting

Customer Question

hi how are you i have an allison at-545rm it is not up shifting on time it will rev out under 50% throttle unless its floored and it shifts perfect! i removed governor it is moving freely. Im thinking modulator?? what are your opinions
Submitted: 10 months ago.
Category: Medium and Heavy Trucks
Expert:  supertech52 replied 10 months ago.
Hi my name is***** and I agree that yes the modulator needs to be adjusted. Hold the throttle all the way to the floor and adjust modulator cable to where it is pulled out to that point. Just so that the modulator cable does not limit throttle travel. Let me know if I can be of any further assistance to you, and thanks for your question. Have a nice day. Sincerely, ***** *****
Customer: replied 10 months ago.
This one does not have a cable it's electronic does that change anything?
Expert:  supertech52 replied 10 months ago.
Ha LOL, yes that changes everything. Wow, I apologize, is there a switch on or near the throttle cable?
Customer: replied 10 months ago.
So you mean in a switch near the throttle position sensor? The footpedal because that's electronic too ?
Customer: replied 10 months ago.
Pretty much what is going on is 2nd to 3rd shift is extremely delayed in less under wide-open throttle The motor will run about 2500 RPM some under mid throttle and won't shift in less floored
Customer: replied 10 months ago.
Any other ideas?
Expert:  Jeremy replied 9 months ago.
My name is ***** ***** I will assist you with your question today. I'm an independent contractor and I don't get paid until a rating has been made. We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence! Are you having any shifting issues in any other gears at all? Any delayed shifts or shifting later than usual or is this only happening between 2 and 3?__________________________________________________________________________________________________________________________You want a 5 star service and I want to provide a 5 star service. Please consider that I don't know your skill level as well as I can't see, touch, smell, hear the vehicle/machine in question. Please provide as much detail as possible and I will provide as much back. Once an answer is provided, you should see a rating screen. Please rate my personal service to you. The ratings are my personal feedback,they are not the site feedback. Thank you for allowing me to assist you through Just Answer! Jeremy
Customer: replied 9 months ago.
It tends to be a shifting delay from 2/3 to 3/4 under half throttle It will shift fine under full throttle
Expert:  Jeremy replied 9 months ago.
Hmmm... Do you have the Allison software by chance to do the adjustments with this transmission being fully electronic? Have you been able to see what the pressure is by chance coming off the pump and to the cooler to see if the pump in the trans is acting up? Any codes coming up for that shift solenoid? Does the fluid show any signs of contamination? How about the filters. When were they changed? Last fluid change out and refill?
Customer: replied 9 months ago.
I do not have the software it is fully electronic? At that year? I was thinking modulator valve and there is no code as far as the diagnosis on the dash and the fluid looks new nothing at all governor is not sticking either are there adjustments on the valve body?
Expert:  Jeremy replied 9 months ago.
Yes, that year if I recall the modulator has no cable. It is electronic controlled and the software is needed to make the adjustment. On the valve body, unless you have the Allison tools, I would touch it. That is the valve body that has the little pellets in it and they can be a nightmare to put back in with out that plate that holds them in place from the kit.
Expert:  Jeremy replied 9 months ago.
The only way I know hoe to adjust them on that year is with the software and the little wrench and the adjuster tool.
Customer: replied 9 months ago.
OK is there any preset adjustments that can be made I'm pretty good at the mechanical side I just don't know the spec and also could the modulator valve be dead causing this issue?
Customer: replied 9 months ago.
If I get line pressures during shift and under load with that help?
Expert:  Jeremy replied 9 months ago.
Certainly. If you can get them at idle that will help for I can see if the pump is weak.
Expert:  Jeremy replied 9 months ago.
Do you have the serial number on the Alison by chance?
Customer: replied 9 months ago.
I could get ahold of it and let you know! Thankyou!
Expert:  Jeremy replied 9 months ago.
You're welcome.
Expert:  Jeremy replied 9 months ago.
I see you viewed this and this is still showing as an open question due to no positive (3 stars or more) rating. Were you not pleased with my service to you or is there a rating issue? Please let me know if you still need assistance with this, if there is a rating issue, and/or you need more time to respond. I like to make sure all my customers are satisfied since you did pay a deposit for me to assist you, whether I’m paid by a positive rating feedback or not. We can continue where we left off or start over if needed. Also, if you need diagrams, instructions, etc please don’t hesitate to ask.

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