[rodeome]

Anybody know what is up with the recall for all 2004 and 2005 C5500 and C4500's allison transmission? My friend just got a letter indicating a recall on the tranny and something else to do with the exhaust brake. Looking for input.
Rodeo Me

 

[Wayne74]

I got the letter also but have not gone to the dealer yet. I think it has something to do with the trans down shift when the exhaust brake is on. Will try to get to the dealer this week.
Wayne

 

[Dirt Dog]

THe simple explanation is that the way the clutches operate during exhaust brake application can cause the C1 clutch to fail. The C1 clutch is used in 1st thru 4th gears.

Get the campaign done ASAP, or stop using the exhaust brake until you can get the truck in.

 

[run2trouble]

Anybody have the campaign number?

 

[Swoll]

I have the letter and doesn't have any particular campaign number on it, but i also got a field action card with the number 2005FA03 on top.

The letter says just to reference this letter and make an appointment.

 

[Swoll]

I just got off the phone with Allison (800-252-5283) and they told me that I have to take it to a Allison center not to the dealer. Simple reprograming should take about 1 hour.

 

[wa3pnt]

A MAJOR reason for my purchasing the C4500 was the braking capability of the Engine Brake in conjunction with the Allison.

I hope that the changes do not seriously degrade the braking capability.

 

[JeF4y]

I got my notice last week... Actually I'm hoping that it puts a tiny delay in between when the ex brake kicks in and when it downshifts... For the last year, I've basically used the ex brake manually because I hate the way it kicks down as soon as the ex brake comes on.

 

[Chooch68]

Had mine fixed by Valley Power in Irvine. Nice Shop. Dont really notice a difference in down shift from 5 to 4. Its still pretty rough. Not sure what was reprogrammed.

 

[cowboydoc]

I had mine done today and I don't notice anything different. Took them two hours whatever they did. They said they just reprogrammed the transmission to work better with the engine brake.

 

[ldanes]

It was just what "Dirt Dog' in his stated in his post. The C1 clutch issue.
I had mine done yesterday and the transmission does shift a lot smoother.
I real notice it in the down shifting in the hills with a load.
Thanks again Dirt Dog for the correct information. Do you have an inside line on information on Chevy action letters? Lou

 

[wa3pnt]

Idanes

When you say "I notice it in the downshifting in the hills with a load" could you please elaborate.

Are the shifts softer (slippage or unlocked converter)? Firmer? Delayed?

Thanks

 

[ldanes]

It seems to be quicker and firmer, no delay. I pull a F-250 PSD crew cab and a cab high shell with work tools. I feel the re programing was helpful with the
activation of the exhaust brake. Just my feelings. Lou

 

[wa3pnt]

Thanks for the info.

I was afraid that since there seemed to be a C1 Clutch problem they might degrade the exhaust brake. I pull a 36' 4 slide 5th wheel (17K) and really rely on the exhaust brake on some of the mountains I encounter, like Mountain Springs Grade east of San Diego.

No Allison Service Centers in or around Yuma, but I've got a Rodeo in Scottsdale, AZ the 1st of March and will make arrangements to have the Campaign done while there.

 

[rodeome]

Even though I never got a letter, I took mine into Allison and they checked it out yesterday. What they do is take some number off the tranny and input it to their computer data base to check the software version. My truck already had the latest software and so did not need the calibration. Maybe that is why my exhaust brake has worked so well. Anyway, my friend's 2005 4500 did not have the latest software and her brake did not work. She has upgraded and now is getting the brake checked out. Could be unrelated but who knows. Why would a 2004 5500 have the latest version (mine) and a 2005 4500 not? Go figure.
Rodeome

 

[Dirt Dog]

The software update adjusts the timing of the clutches, it has nothing to do with thw actual exhaust brake itself. As one clutch comes on and another drops off, the clutch timing was just a fraction slow which places too much heat and wear into that clutch. The new software drops out the C1 clutch a little sooner.

 

[tmcblane]

Is this pertaining only to trucks with exhaust brakes?

 

[noelshoeit]

Had it done today. Allison Tech came out to the house and finished the up-grade in twentyfive minutes. What great service from the Allison in Ocala, FL. :cool2:

 

[Dirt Dog]

Is this pertaining only to trucks with exhaust brakes?

Yes