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Everything posted by ElizabethMeyer

  1. I have a buddy who's kid built an RV out of an old school bus (known as skoolies). Unfortunately he broke down within a few a few miles of his inaugural voyage. The shop found both fuel filters clogged but also stated that they found pieces of rubber in fuel tank. I've never heard of that. I know rubber deteriorates and I make it a habit of replacing all rubber lines on old cars that I have restored including an old 76 GMC Eleganza motorhome. Anybody ever hear of that? If true, what else has to be cleaned and flushed to get the fuel system clean and reliable? I don't have the year or make of the bus but I can likely get it if important. Thanks Mark
  2. Don't know. Factory installed on both furnaces. Don't have coach here but guessing there is a bead of silicone between that plate and the coach?
  3. This may be an easy fix for anyone who wants to use their furnace on the road but can't because it keeps blowing out. My horizontally mounted rear furnace intake/exhaust kept doing that while my vertically mounted mid-cabin furnace intake/exhaust worked perfectly. After thinking about it for a while I decided to try introducing something that would divert/obstruct/change the air flow over the rear furnace intake/exhaust. Lo and behold it worked. I tested it at 65 mph multiple times and it hasn't failed yet.The 'device' is just a 2" pvc coupling that I first cut in half lengthwise then cut it in half again widthwise. Painted it silver and attached with clear silicone to the rear side of the intake opening so it could divert/obstruct/change the airflow over the intake/exhaust. I have no idea about the exact dynamics and whether it would have worked just as well mounted on the exhaust but it worked. Now I'm looking forward to a warmer coach on the road. Here are a few pictures. And yes I know even Suburban (spoke with them) recommends not using the furnace while traveling but many of us ignore that advice. Should think of a fancy name for it like the "Dynamic Aero Turbulator" and sell em.😄 Mark
  4. As promised. I finally finished my testing of the slow key cycle method recommended by Allison to avoid randomly losing my full throttle downshift ability. The recommendation was to wait 5 seconds in the on position before engaging the starter. I exercised an abundance of caution and waited 10 seconds. I tested it 10 days in a row with 10 cycles each road test. I would start it up in the storage lot, get out on the road, do a full throttle downshift at shift points that I knew it should respond to a full throttle downshift request, validate it worked, then pull over and do another key cycle for a total of 10 cycles per trip. I have a call into Allison to review my findings and determine their next steps in fixing this bug or design issue. I'm not exactly sure how they are categorizing it. Please pass on this information to anyone you know that might be having some performance issues with their Allison trans. Hopefully Allison will communicate this and other issues out to their field team and repair centers. No one I dealt with, including the most recent team from Allison and Cummins, knew anything about this. It wasn't until I got these two tenacious individuals who chose to own the problem rather than simply say their side looked good, that we discovered it was known by Allison and I wasn't exactly alone in experiencing this. Mark
  5. Day 4 and all remains good. 4 days and 40 key cycles. I'll report back when I finish the 10 days but the slow key cycle work around is looking good.
  6. Day 3 tests all positive. Tomorrow, Day 4, will be statistically significant because it has never stayed in "working" mode 4 days in a row since I have been aware of the problem and starting tracking it. I'll post Day four and then wait to post until I have finished the rest of this week's daily tests until I finish Day 10.
  7. Day two: slow key cycle worked again. 10 cycles of off, on, wait 10 seconds, start, drive, try a couple of full throttle downshifts at known shift points. Repeat.
  8. Hi, This is Mark, the OP. Thought I would give a quick progress update. It may help people with an Allison 2500 who are experiencing no downshifts even at full throttle. I've worked with two different teams of Allison and Cummins techs over the last 6 months. That is in addition to the original time and money spent at Allison and Cummins trying to get this thing diagnosed. The first team worked with me down at Tiffin in Red Bay. That ended up with no fix and Cummins and Allison nicely pointing fingers at the other and Bob Tiffin pointing me to Freightliner. By this point the ECM, TCM and TPS had all been replaced without fixing the problem. The coach still would randomly not downshift at full throttle under conditions I knew it should and could. I had demonstrated that to the techs over several days. I had just about given up when I called Cummins about warranty coverage and got a tech person who was genuinely interested in my problem. That got be kicked up to Level 3 and I got a tech that was EXTREMELY tenacious. He ended up arranging a meeting with me, himself and an Allison tech for two days down at a local Cummins shop. Best two days ever with both guys taking turns plugging in their PCs and discussing possible theories as they were gathering and diagnosing data and findings. The end result is that it looks like it is a software bug on Allison's side. Not confirmed yet but data is pointing that way because they are seeing this problem elsewhere on other vehicles. It is is tied to, and triggered by, cycling the key on and off. The thought is If you cycle the key off and then on too quickly, the software pulls the wrong value for the "road speed limit" parameter and that in turn causes the transmission to not downshift at full throttle. I am just starting to test this theory by cycling the key from off to on and then waiting 10 seconds before starting the vehicle. This slow cycle supposedly allows the data to fully load into the TCM. Quicker cycles cause that load to get interrupted somehow. I should finish my testing this week. Today it worked correctly 10 times in a row but my experience is that those results are not definitive. My data to date says that anytime I leave the RV sitting over night I have about a 50% chance of it being in "working" mode versus "not working" mode" the next day. So until I get a few more days of those data points I won't really be comfortable saying this slow cycle works. Allison says that they are doing the slow cycle on a fleet of garbage trucks and it has worked 100% of the time. Just to refresh what my problem is. I know my trans shift points at full throttle by heart now on flat roads in good conditions. It will downshift at 25, 35, and 45 (other points too but these are the three I use as test points) at full throttle every time when it is in "working" mode. When it flips over to "not working" mode after a key cycle, it will NOT downshift at those same points. It just slowly accelerates. I'll keep everybody posted on the rest of my testing this week. Mark
  9. I purchased the coach 1.5 years ago but never tried driving with the furnace on until this fall. It happens every time from what I can tell. Just went on a short trip today at a max speed of 45 and it was off when I arrived at my location but nowhere near it's setting of 68. I'm assuming it is the outside wind but as I'm sitting here typing I can't say for certain. Could be other reasons for shutting down. When I get to where I'm going I just flip the switch to off and then back on and it starts up immediately.
  10. My rear Suburban furnace blows out when I drive. My mid-cabin furnace works fine when I'm driving. The only difference that I can see is that the mid-cabin intake and exhaust vents are vertical and the rear furnace vents are horizontal. I'm pretty sure on my unit the rear heats the wet bay so I would like it to work. One difference that I just thought of is that the mid-cabin may be a few more BTU. I know that Suburban doesn't recommend this use and I've read that there may some states that don't allow it. I want it to work. Mark (aka Elizabeth, the true forum member)
  11. It was fine but very slow to load up or recalculate. That may be because the memory module was failing and ultimately failed. The screen would blank out and fill with hundreds of little blocks with the words "GIR LOW MEM" in them. You would have to shut it off and then go into settings to select the map which the memory failure would un-select. This worked a few times but the problem quickly got worse and it would fail within five minutes of resetting. Stupid money to get repaired and the part is taking over two months to arrive at the repair facility. I was in a hurry to get it fixed which is why I went with the repair but I would do a lot of research on alternatives before I would go this route again. Mark
  12. I was asking in general. Thanks again to all who responded and Merry Christmas! The bus video more than convinced me there will be no "winging" it.
  13. Ouch!!!! Yeah, don't want to do that. Not even at slow speeds. Mark
  14. Thanks for the replies. Coach is a 2015 Tiffin RED 33aa. 35 feet long, 13 feet high, 31k pounds fully loaded with full fuel, propane, fresh water and toad. Wife is getting the Truckers Atlas. Not sure what else we'll get, have to look up the suggestions posted. Does anybody just wing it? I was just talking to a buddy of mine a few minutes ago who has traveled 150,000 miles in a 34 foot Class A and he says he has never used anything other than paper maps and now Google maps. Just asking, not suggesting it. Wife is a cautious soul so it would never happen anyway. Personally we would like to just use our phones and not screw with the Kenwood. Mostly because it is slow and hard to access for my wife since it is the driver's cockpit and angled towards the driver with no ability to swivel it towards her. To see it, she has to unbelt and kneel in front of the stupid thing. Mark
  15. Our Kenwood is in the shop for the next few months getting repaired. Yep, the next few months waiting for a part. Crazy. The problem is we are leaving for a month long trip from Chicago to Texas and we don't have an alternative for bridge clearance - our main concern. We both have Google Maps on our phones and use that app frequently in concert with the Kenwood. Any apps available to add on to Google Maps? We really don't want to buy a stand alone GPS since our Kenwood is coming back to us some day but I'm not going to cheap out and not buy something only to end up with many thousands and thousands of of dollars in roof repairs as I scrape off the top foot or so of my coach😁 Mark (aka Elizabeth the actual forum member and my wife)
  16. Here is a another update. Cummins Level 3 was supposed to meet me at the Cummins dealer on Tuesday but the stupid coach would not flip into "not working/derate" mode. Drove around my neighborhood for almost two hours, stopping, starting, driving, stopping, starting, driving. Must have cycled that thing 60 times and couldn't get it to flip. Called the dealer and let him know that I would continue to try. The Level 3 guy was already there. About 5 minutes later I got a call from the guy and he said he wanted to change plans. Instead of having me come down he was going to requisition a recording device to capture what was happening and he would call me and come to my house to install as soon as he got hold of one. Even more importantly he was already in discussion with their Systems Integration team, the guys who work directly with the other vendors to make all this stuff work together. They are going to work with him to find out who is not sending or receiving the signals properly and get the vendors' systems working together and keep me out of the finger pointing that has been going on for over a year. In other words, own the problem. HALLELUJAH. Haven't heard back yet but I'll be following up on the 26th if I haven't heard by then. Betsy and I are leaving for a month long trip to Texas so I'll have plenty of opportunity to demonstrate the "not working/derate" mode to his new recording gadget. I did ask him why the first gadget didn't capture what he needed and he responded that it had some glitches and the Systems Integration team also wanted something different than what the first device was capable of. Stay tuned!
  17. Coach has 15K and I've put on 10K of that. If the problem is mousies, they got it before I purchased it because this problem has always been there for me. Loves to eat them mousies, mousies what I loves to eat, bite they little heads off, nibbles on they little feets. (B. Kliban - 1975)
  18. Well, a little update albeit without much data. Went down to the dealer Wednesday and drove around with the interactive device plugged in and sending real time data to the Level 3 tech. He had them replace the manifold pressure sensor (I think?) and we repeated the tests in both modes "Working" (Power) and "Not Working" (Derate) with no change. Now the Level 3 tech is coming to the dealer on Tuesday just to see me. I am now the guy you never want to be. The guy who has a problem that is stumping everyone. Yay! This will be the third time I will be going down. A couple of good things. One, I have been able to arrive with it in "Not working (Derate)" mode both times. The first time it took me running around the neighborhood like an idiot and cycling the key 30 times before I could get it into "Not working (Derate)" mode. (Stop, neutral, key off, key on, drive, hit 26 mph, downshift working - CRAP, repeat 30 times till it WON'T downshift.) Wednesday it started out in "Not working (Derate)" mode. I was also able to get it from Derate to Power mode and back to Derate mode after 6 or seven tries for each flip down at the dealer. It does appear that everybody is leaning towards the engine as the culprit for not making power when it should but nobody has identified the cause yet. It also seems that warranty will cover at least the parts and I'm hoping the labor because I'm burning a fair amount of tech time. Now we have 4 new parts: ECM, TCM, TPS and the pressure sensor. I am providing them with the info from you guys but I'm not sure it is registering. Mark
  19. The "working" mode and "not working" mode are my terms. I use them simply because they are easy to understand. Everything works or it doesn't. I think the tech used the terms "power" mode and "derated" mode. Those may be more accurate but what the **** do they mean to the average guy? Also, not in an over rev mode. Actually it is under revving. This has been one of the points of contention between Cummins and Allsion. Allison is saying they are dong what the engine is telling them to do - partial throttle so no downshift required. Cummins is saying they are responding to a call to derate the engine. This is where I get so frustrated because they each wash their hands of it rather than trying to find out exactly what is causing this miscommunication. in the systems. The good news is that during this last go around Cummins is starting to acknowledge, or at least consider, that they may not be making power. It helped immensely that the Cummins shop manager worked with the Allison tech in the near past and stated that if Darren (the Allison tech) said it wasn't an Allison problem then it wasn't an Allison problem. Herman, unit is 100% stock. Rich, nobody has run that test. Mark (aka Elizabeth - my wife and the actual FMCA member)
  20. Rich. Thanks for the continued responses. I have a 2500 Allison. I''l share your thoughts with the tech when I am down there on Tuesday. The only thing that will cause my issue to cycle from "working" to "not working" is turning the key off/on and shifting from Drive to Neutral and back to Drive after starting. However, cycling the key won't always flip it from one mode to the other. Taking it down last Thursday I had to cycle the key 30 times (cycle, drive, cycle, drive, etc.) before it switched from "working" to "Not working". Once I got down to Cummins, and we finished the "not working" data gathering, it took me just a couple of times to cycle it back to "working". Does that seem more likely to be a wire issue or a sticking electrical device (whatever that might be)? They were talking about some sensor or device that "sweeps" when you turn the ignition on and were speculating if that might be the issue. Above my technical pay grade. Mark
  21. Well, the PITA process continues but with some hope too. First the whining. Tiffin has basically, and in a very nice way, opted out of the diagnostic process. Their advice is to take it to Cummins or Freightliner. The problem with that is I know what the responses will be because I''ve been there done that. Everybody points to everybody else and the financial bleeding goes on with no progress. My hope was that Tiffin would own the problem because of their influence with their vendors. I was looking for leverage not necessarily financial assistance. They did to a degree but when the initial effort failed that was pretty much it. Then, I got excited with Level 2 at Cummins because they seemed very interested and told me that they often solved others problems. Great. Got an appointment scheduled at Cummins in Hodgkins Illinois and contacted Level 2 to make sure Hodgkins had any and all background data from the two techs who worked on it down in Red Bay. Crickets. Get down to Hodgkins and, surprise, surprise, "nothing wrong on our end you need to take it to a great Allison shop in Grand Rapids, Mi." NOOOOOOOOOOOOOOOOOO! Now some good news. I call Cummins Level 2 and BEG him to help get this solved. Told him my experience with Hodgkins was exactly what I expected and without his involvement I was going to get exactly nowhere. So he calls Hodgkins and calls me back. I'm to go back to Hodgkins the next day (yesterday) and they have been told what data to capture for Level 3. I also provided some additional information that when the trans wouldn't downshift at full throttle, the turbo boost was also low - never above 20 - psi. (Didn't even know I had a turbo boost gauge. Why didn't the Cummins tech at Red Bay notice that?????) So I get down there, we do the test trips, they gather the data and the tech starts acknowledging that Cummins has problems with turbos, turbo actuators, etc. that could cause low boost and yet throw no codes but causing the transmission to see no power and therefore no downshift request. FINALLY SOME CRITICAL THINKING TAKING PLACE. So now I am going back next Tuesday to do some more trips with an interactive CAN bus tool so that Level 3 can see what is happening in real time from wherever they are located. No idea what the costs are going to be but it sounds like the parts are under warranty. Don't know about the labor. It would be helpful if anybody who knows the warranty with certainty wouldn't mind chiming in. Keeping my fingers crossed. Mark
  22. Philc, We looked at the Forza - nice coach. I did get this programming change done when I bought the coach (used) about a year and a half ago. Mark
  23. Rich, I don't have a clue. I forwarded your earlier response to Gary Harris at Tiffin and he noted that he had been thinking along those lines too. I'm forwarding him this email too. I spoke with Cummins today (trying to get warranty information) and ended up talking to a guy who seemed very interested in the problem and mentioned a Level 3 group that works on odd issues like this when the field tech and second level support get stymied. He is going to contact the field rep to see if he pulled data from the system when I was down in Red Bay. He wants to ship that data to the mysterious Level 3 group. My note of caution to him was that I was interested but I need somebody to own the problem and coordinate with the other vendors because it doesn't do me any good to have them go "no problem on our side. Been there, done that, cut the large check. Coordinating with the vendors was why I ended up in Red Bay. Gary Harris made that happen. Mark
  24. I appreciate the thought, and no, they haven't. That said, it full throttle downshifts fine in "working" mode which it wouldn't do if it was geared incorrectly. It would have the lack of full throttle downshift all the time, right?
  25. Manholt, Both the Cummins tech and the Allison tech have plugged in. Multiple times. Cummins shows 100% response to TPS full throttle request in "working" and "not working" modes. Allison shows 100% in "working mode but only a partial throttle request in "not working" mode. What the Allison computers shows in "not working" mode is what I term a rolling throttle response. Meaning, that when I have the pedal to the floor, instead of seeing 100%, Allison sees a request for 40% that then rolls up to 90% or even 100%. It doesn't always hit 100% often pegging around 94% throttle request. Mark
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