randome downshifting

the4wheeler

--->(Something Funny)<---
May 4, 2008
254
0
0
Ventura County SoCal
got a 06 C5500 at work hear LLY Allison bone stock with 82k

last fiew days driver saying it will randomly at highway speeds cruzing 65-70 will downshift all the way to 1st and remain locked there and wont shift out he says he can shut the truck off for 20min and re start and some time will go back to normal and some times wont git out of first starting out says it has done this sever times during the week. cralled under there pulld the main conector off has a little bit of oil in it , gona blast it with contact cleener and drive it my self.
the trans service light is not on but the CE light is ill see if i can connect up and pull a code later

any one have a idea what could be up other than the main wiring conector
 
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Nacho05

<---Shaken, not stirred!
Aug 28, 2006
29
0
1
Los Angeles
my truck downshifted all the way to first when it had the #2/#7 wiring problem. Very scary when you are in the fast lane with traffic and big rigs to your right.
 

the4wheeler

--->(Something Funny)<---
May 4, 2008
254
0
0
Ventura County SoCal
company opted to take it to the dealer and have it looked at under warranty so i dident git a chance to pull codes
10 bucks tho the dealer comes back finding nothing or says you have to take it to a Allison dealer for trans. issues which is thayer usual cop out being a med.duty truck thay don't like touching them even tho they are the only ones in the county whom can work on them.:rolleyes:
ill post back if they find any thing
 

stacks04

Member
Nov 16, 2007
792
0
16
Terryville,Ct
most dealers wont touch the allison. alot has to do with the early ones. gm specifed they do a trans swap if and when there was an issue. and the parts availability isn't the greatest either from gm. your probably better off going to an alli dealer:rolleyes:
 

the4wheeler

--->(Something Funny)<---
May 4, 2008
254
0
0
Ventura County SoCal
just herd well they found nothing with the trans but it had 2-3 engine "drivibilty" codes in it (dealers words) i don't know what the hell they found but they are doing injectors on it :confused: i drove it a some time before and defenetly did not act like a truck that needed injectors nor did the guy that drove it to the dealer felt like it needed injectors
warranty work but i think that its kinda odd. maby even a bit shady

these motors arnt know for loosing injectors are they?
should have it back tomorrow ill check the work ticket see what they found
 

WolfLMM

Making Chips
Nov 21, 2006
4,005
26
48
38
AL
What a bunch of F ups? Injects are you serious?! I sometimes wonder where gm gets there *most* of their techs...
 

WolfLMM

Making Chips
Nov 21, 2006
4,005
26
48
38
AL
I seriously doubt bad injectors will cause downshifts like that..if they are as bad as he says.
 

the4wheeler

--->(Something Funny)<---
May 4, 2008
254
0
0
Ventura County SoCal
i havent forgotten to update
truck came back Friday and the recite went strait to accounting

just been busy to go in to the offace and dig it out ill git it posted up soon
 

the4wheeler

--->(Something Funny)<---
May 4, 2008
254
0
0
Ventura County SoCal
so it turns out that they did not do injectors they started out to do so and found the MAP wiring had been rubbing on the air filter housing and the post intercooler piping and had warn throu the wires