MH4000, dropping out of gear

[coolburns98]

I have a 2004 Holiday Rambler Navigator,2nd owner and had it a little over a year.
Two problems 1.
Lately, at no consistent interval, but low rpm, the tranny pops out of gear to neutral. The display flashes and the check trans light flashes also. Has anyone experienced this situation ?
2. I have the rig at Gibbs International Truck Center in Oxnard, Ca. They have had my Navigator for a week and cannot seem to find the ECM and/or where to plug in to test. I had a previous tranny problem last April, when passing through El Paso, Tx. Stewart and Stevenson,there, did a nice job, quickly, and got us back on the road.
Both are authorized Allison dealers.
I am trying to help expedite the fix, as well as learn more about my coach.
Any help will be greatly appreciated.

Coolburns98
2004 HR Navigator
Roadmaster Chasis
Detroit Diesel, Series 60

[marjoa]

Well, if it were me and they had my coach for a week and can't even find ECM or where to plug it in—authorized Allison dealer or not—I'm looking for someone else. Jeeze.

Maybe this will help ya find another qualified shop nearby.
RV Service Reviews

Good luck.

[coolburns98]

Originally Posted by marjoa

Well, if it were me and they had my coach for a week and can't even find ECM or where to plug it in—authorized Allison dealer or not—I'm looking for someone else. Jeeze.

Maybe this will help ya find another qualified shop nearby.
RV Service Reviews

Good luck.

Thank you. I guess I just needed a swift kick.[emoji30]
Thanks again,
Jerry

[coolburns98]

Just to give everyone an update. Finally told Gibbs to wrap it up, we would take our chances on the road. They only charged us $420. For two weeks storage. That is about what it amounts to, nothing accomplished.
Left there last Saturday AM, managed to get 70 miles before tranny died on 210 frwy near Pasadena, Ca. Sat there for five hours before getting towed to Whittier Elks Lodge. Monday morning, called Valley Power in City of Industry. They sent a Mobile Technician out to replace the TCM. That was done on Wednesday morning. Everything looked good.
Took off for Phoenix,started acting up again, but just at low speed, downshifting. It was fine on the road. Friday morning, nothing to lose, took off for El Paso. Made it to Tucson. While getting off to fill, the power to shift pad died. Managed to”coast “ all the way into driveway of International of Arizona. “Devine intervention “, is all I can say. After they opened, got towed into their yard. A service tech was put on the job , and within an hour, he found the problem. A wire was broken, just barely holding together. He replaced it and we were on the road again.
We are currently in Ft Worth, Texas. We drove six hundred miles without a problem. What great people. I can’t recommend highly enough, the fine folks at International of Arizona, in Tucson, Arizona.
I know this was a long update, but worth the read.

[CoCoDave]

Originally Posted by coolburns98

I know this was a long update, but worth the read.

Thanks for taking the time to post the update. A broken wire, a corroded or loose connection, are very common causes of flaky transmission behavior. Our experience paralleled yours. Had I known about International Of Arizona in Tucson, I may have taken it there.

As it turned out the transmission worked well enough to get us to Phoenix via home in Washington. I found the offending loose connection in the +12VDC wire going from the battery to the Vehicle Interface Module (VIM).

In any case thanks for documenting another case of problems caused by failed wiring connections. My impression is that this type of problem is far more common than failed computers, e.g. TCU, ECM, TCM, etc. Maybe it will help owners do a sanity check on a proposed computer replacement out in the future.

FWIW

[acampingwewillgo]

Wait, Wait, I want to know More!!! :-) Like you, I am still having issues with my HD4060 Tran's. It's an on again off again issue where it will go into neutral, then back into gear and Yes, I get the check engine light too.

I have to admit, I haven't worked on it lately but it's keeping me from planning any trips.....one thing we also have in common, I'm here in Camarillo and while I hate that you had this problem storing your RV in Oxnard with nothing getting done, I'm happy to know, they know little to nothing about the Trans. Our local CAT dealer(Quinn) won't even touch a Motorhome any longer since they are out of the RV engine business.

I been advised by many that it's an electrical issue, but trying to find exactly where to start is an problem. I've done quite a bit my self, Sprayed cleaner the touch Pad contacts, pulled the ECM and sprayed, checked fuses and wiring...nothing found yet. I'm in the process of replacing my alternator and running some new cables, thinking this may be an issue also(I need a larger alternator anyways because of all the junk I run going down the road(resid fridge, small fridge, a new 120 v freezer ect ect). I was going to stop in Fresno on the way home a couple months ago at a location that seemed to have an idea of what they were talking about but after inquiring a tad more while they knew there stuff, I was quoted that trouble shooting MIGHT take 8-10 hours at 180-190.00 an hour.....I thought, I could do a lot of my own trouble shooting for that cost. Anyways, if you knew what area they found that wire, it might give me a starting point...maybe???

[acampingwewillgo]

Oh....CoCoDave....excellent info....I've been checking on the wires I can see but I'll have another look. I noticed before leaving my last campground when coming home, I really cranked on my Chassis battery connections which seemed to eliminate the issue for a bit hence my alternator/ upgrading cables thought(need to do it anyways). It does not seem to make a difference on how jarring the road surface is....a faulty connection...maybe but I'm thinking more a corrosion issue than a broken wire?

[CoCoDave]

Originally Posted by acampingwewillgo

Oh....CoCoDave....excellent info....I've been checking on the wires I can see but I'll have another look. I noticed before leaving my last campground when coming home, I really cranked on my Chassis battery connections which seemed to eliminate the issue for a bit hence my alternator/ upgrading cables thought(need to do it anyways). It does not seem to make a difference on how jarring the road surface is....a faulty connection...maybe but I'm thinking more a corrosion issue than a broken wire?

Don't know about your coach, but typically the transmission and engine control modules (ECM, ECU, TCU - pick your nomenclature) each have a dedicated pair of wires to supply 12VDC power. Some take it directly from connectors on the battery posts others, like mine, use heavier 2 gauge cables to take the power to a distribution point and then smaller gauge (14 to 10, depending) wires to the respective control modules.

I'd focus on the beginnings (vicinity of battery) and ends (vicinity of control module) of those smaller wires. There's likely to be some splices/connections near both ends. I'd look really hard at those. If your engine is cranking OK, the big cables and connections are probably adequate.

Good luck!

[coolburns98]

Good morning. I just read your message. I certainly know how frustrated you are.
First (I have learned) call the Allison Regional Office for California, if you need it let me know. Ask them for a list of “Authorized “ Allison dealers, don’t trust any list of same from an old reference list,then call them. Like we both found out, many don’t work on Motorhomes any longer.
I don’t know the configuration of your engine compartment, but mine has both starting batteries located between the bumper and the engine. The wire that was bad, went from the battery to the connection to the tcm. If you are good at testing voltage with your meter, then maybe you can figure it out. I am not, therefore, I spend the money. The key is, in my case, finding the right people to do the work, the first time. I know it would have saved me about three thousand dollars. Good luck. Call Allison first! You will save time and time is money.

Coolburns98
2004 HR Navigator
Detroit Diesel, Series 60

[acampingwewillgo]

I know I need to get back outside and just do my due diligence on the wiring. I've kinda put the MH on the back burner right now, concentrating on getting some much needed work done around the house. My batteries both house and chassis are located to the driver side rear of my coach(Behind tires and in front of rear bumper). For the life of me , I can't picture anything but the large alternator cable coming off the chassis battery although I know I have additional + wires tied in because of the echo charger I added year's ago. My ECM is located way up front under the drivers area compartment.

Just to be sure, I've opened up the ECM up front nd sprayed the contacts and I also removed the in line fuses within the ECM...I'm assuming that's where the ECM is fed power via those fuses within the unit itself? If I'm on tract with that, it would be relatively easy to run a temp wire from battery to ECM to see if that solves my issue....if it did, than I could concentrate on getting a couple of new wires run up front?

I appreciate your input, Thank You so much and your correct, its very frustrating seeing that I try to do as much of my own work on this darn thing(Motor home) as possible. Thanks again.... Dwight

[acampingwewillgo]

Don't know if anyone is still following this thread but here goes:
I have quite literally been schooled on the Allison Transmission. Lots of trial and error but still NO solution. I have replaced my ignition switch, I bought a used VIM(it was good but didn't solve my issue), bought a couple new relays and 10 amp fuses, ran temporary new large gauge wires up to the VIM(both positive and grounds) directly from battery, cleaned and checked pin connections, Put new terminal block in for positive wires(junction of #8 and wires going to VIM), checked voltage at the Pins and grounds of my ECU both for power and brightness of test bulb(to determine if wire has some type of resistence...it didn't), did find a ground wire that was loose at Negative junction for VIM..decided to remove Crimp's and temporarily put wire nut on the #8 Ground and all the #14 ground going to VIM.

I'm left thinking that it must be the ECU but finding a place that can test it and actually know what their doing has been a task in itself. I have chatted with a few places in Texas, North Carolina and Minn and been quoted prices from 500-1250.00 on rebuilding my ECU. The place I got the used VIM at(Complete Coach Work's in Riverside) may be a location that can test and repair ECU if I determine that's the last resort. They are more a commercial Bus rebuilder and there facility is HUGE...I got some phone calls to make and pick some more minds before I give up!!! Hey...I'm always open for other thoughts????
Dwight

[CoCoDave]

Did not see this outfit suggested earlier but they get good buzz for shifter and ECU repair.

Allison ECU & Shifter Repair

FWIW

[acampingwewillgo]

Well Now, this morning while nearing the end of my rope with all the frustration trying to tract down this problem/solution, I made about 6-7 phone calls to different ECU rebuilders, Allison Authorized Service locations and I figured what the heck, I'll call Allison's help line again.

I'm not going so far to say my problem is solved but the new instructions from Allison has made a difference so far(Trans holding steady and not faulting in my preliminary tests in the drive-way.)

The instructions were as follows, for my vintage WTecII and my older model ECU was first, Cut/Remove the incidental Chassis Ground that was fed through ECU(B-10 Pin, wire # 144)...and then isolate the ECU completely from Chassis. Of course they made an isolation kit for this purpose but in the calls that I made subsequent, no one had the part number. So, me, in all my ingenuity, put two 3/4 pieces of plywood together, mounted the plywood to the metal and then mounted the ECU to the plywood......isolated.

I redid my Transmission Isolated ground wires and at this time, I took the two #14 positive wires feeding the VIM and tied them directly to the isolated #8 battery wire with a wire nut...for now anyways. Plug everything back in....and so far..so good! I'm hoping and praying this is it...I'll come back and let anyone who cares to know the results after a test drive of a few miles.
Hope this info helps others when they are confronted with the dreaded 35-00 Code!!!

[coolburns98]

Keep sharing your thoughts and adventures with your coach. Something, anything you say could help someone else. Good job!