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Dakrism · 10-19-2021, 11:34 AM

We just finished a 7000 mile trip and we were 3 mi from home and I topped off the diesel and unhooked the toad.

As I followed my wife out of the lot I goosed the coach to get thru a light and suddenly lost power. I was also stuck in 1st gear.

I got off road under an overpass and tried to figure out what happened. The shifter would not move the buttons did not work it just stayed in 1st gear. I had no reverse and I was afraid to shut it off in case it would not start.

I limped toward home and pulled into a vacant lot and finally shut it down.After consulting the manual it said I had gone into "limp" mode.

Before calling my wife to come pick me up I did try to restart and it started and there are no warning lites and it shifts fine,I pulled out of the vacant lot and drove another mile home and backed into our lot here in Florida.

Now, I'm not sure what to do next.Anybody have this happen to them and are their any suggestions???

Skip426 · 10-19-2021, 11:43 AM

What series of Allison transmission ( 2500 or 3000 ) do you have a push button shift pad or shift lever ?

If a 3000 series have you tried to get a code ?

EDIT: Was it raining or were the roads wet?

Dakrism · 10-19-2021, 12:04 PM

Skip,
I believe the trans is the 3000 it is a push button and I have not tried to get a code yet.
The road was dry.

Thanks for the information!

wolfe10 · 10-19-2021, 12:49 PM

You need to determine all the things that don't work when this happens.

Certainly sounds like a 12VDC issue from chassis batteries to at least the Allison ECU and shift pad.

Check chassis battery cables-- clean and tight, including ground to chassis.

Then when it happens again see what voltage is up front and also what else doesn't work-- things like dash HVAC fan. If all things that only work with the ignition on are what isn't working, start at your IGNITION SOLENOID. Check for power in (12= VDC between one large lug and ground/clean metal). With ignition on both large lugs should have the same voltage.

Skip426 · 10-19-2021, 01:05 PM

Engine model info could confirm , trans series .
Cummins 6.7 l , ISB could have either a 2500 or 3000 .
Larger than 6.7l , will have 3000 or , 4000 for the BIG iron.

Dakrism · 10-26-2021, 08:30 AM

Got back to the motorhome today and started it up and the shifter went into gear and I had no Check Trans light on dash. I verified it is the MH3000 model and a Cat engine.

I tried to ck the fluid level using the shift pad and I onto the oL followed by TL. There were no numbers nor any countdown as the manual described. I could not find what TL meant in the manual as it was not shown anywhere.

My dash display for codes is broken and has to worked for a while I use a silver leaf and it did not show any codes at all.

What would the TL mean???? There is never any sign of leaks anywhere.

Skip426 · 10-26-2021, 08:52 AM

I believe " TL " means the trans fluid temp is " Too Low " to provide an accurate reading . I'll double check .

EDIT : Yep , trans sump temp too low , sometimes a code 70 would appear , and that means the same .
Coach would have to be driven 10+ miles to bring fluid to temp .

Chatham · 06-20-2022, 06:51 AM

Quote:

Originally Posted by Dakrism

We just finished a 7000 mile trip and we were 3 mi from home and I topped off the diesel and unhooked the toad.

As I followed my wife out of the lot I goosed the coach to get thru a light and suddenly lost power. I was also stuck in 1st gear.

I got off road under an overpass and tried to figure out what happened. The shifter would not move the buttons did not work it just stayed in 1st gear. I had no reverse and I was afraid to shut it off in case it would not start.

I limped toward home and pulled into a vacant lot and finally shut it down.After consulting the manual it said I had gone into "limp" mode.

Before calling my wife to come pick me up I did try to restart and it started and there are no warning lites and it shifts fine,I pulled out of the vacant lot and drove another mile home and backed into our lot here in Florida.

Now, I'm not sure what to do next.Anybody have this happen to them and are their any suggestions???

This exact symptom often happened in my 2005 dynaquest. Allison found two bad solenoids and bad harness as well as bad fan clutch, trans was overheating and torque convertor not locking up, ck trans will leave you in low gear and not fun on Interstate. Very little warning other than high engine temps. Stop and re start will buy you some time until it overheats again, I'd wait hour and trek on but sooner or later it will happen often till its fixed.i also had 3000 allison reprogrammed to turn on clutch fan at 190f instead of 220f.trans overheating soon overheats engine due to constant high rpms in several gears as trans torque convertor failing to lock up.
2005 dynaquest

Dakrism · 06-25-2022, 10:15 AM

Quote:

Originally Posted by Chatham

This exact symptom often happened in my 2005 dynaquest. Allison found two bad solenoids and bad harness as well as bad fan clutch, trans was overheating and torque convertor not locking up, ck trans will leave you in low gear and not fun on Interstate. Very little warning other than high engine temps. Stop and re start will buy you some time until it overheats again, I'd wait hour and trek on but sooner or later it will happen often till its fixed.i also had 3000 allison reprogrammed to turn on clutch fan at 190f instead of 220f.trans overheating soon overheats engine due to constant high rpms in several gears as trans torque convertor failing to lock up.
2005 dynaquest

Thanks for yur post! I have driven home from Florida to Indiana with no futher problems and I intend to get to an Allison dealer to have them ck the tranny soon.