wolfe10

I did a little research and came up with this guy/company that troubleshoots/repairs Allison shift pads and ECM's: http://www.transmissioninstruments.com 866 439 9779 John Kopalek.

Jim, See response to your refrigerator question on your other post, same issue. Brett

Jim, An easy "suspect" for blowing that fuse is a shorted out heating element. Unplug it (with power off). Put in a new fuse and see if it holds. If so, you have identified your culprit. The heating elements are not expensive or hard to replace.

I am surprised that turning on the bathroom vent fan helps. That would create a vacuum in there in if there is any leak between black or gray tanks and toilet, sink, shower, etc it would suck air from the tank. Again, you need to trace the source of the odor and cure that. Brett

Correct. Navistar/MaxxForce choose to use high EGR and modified engine perimeters to control emissions to meet the much stiffer 2010 EPA standards. Others like Cummins choose to run the engines more efficiently (improved HP and economy) and use a "catalytic converter" to clean up the exhaust-- just like we have had on gasoline engines since 1975. The DEF has to be injected AFTER the engine, as it works in the converter. Burning it in the engine would not work. Let's keep this in prospective: If you have a 15 gal DEF tank and get 8 miles per gallon, that will last you 15 gal times 50 gal diesel/gal DEF times 8 miles per gallon= 6,000 miles of driving on a tank of DEF. Then pull into a Flying J, etc and fill the tank. Your power and MPG will be improved over an engine that does not use DEF. It IS a trade-off-- more complexity and DEF vs not quite as good power/MPG.

No, many RV's do not have an inverter. Because of the variations in how they are wired in an RV, you may just have to search for one. They can range from a small inverter to, say, power a TV to a large one that can power things like a microwave. Older and lower end coaches generally did not come standard with inverters, but many did install one. They also often require a larger than OE battery banks.

Not all motorhomes have ATS's. Follow your shore power cord wiring from side of coach and/or generator wiring to/toward the 120 VAC breaker box. The intersection of generator output and shore power will be the ATS or a plug that will allow you to plug in the "source" you want to use to power the 120 VAC items in your coach. Most generator pickups in the fuel tank are above 1/4 tank so you can not strand yourself by running out all the fuel powering the generator. But, it should not require a full tank.

Electric blankets take a lot less power than space heaters, but produce far less heat. You should have the amp/watt rating on each to compare. Not that big a deal if you are plugged into shore power, other than increased power consumption with the space heater. But, it could be a critical difference if you are trying to run it off your batteries through an inverter. It would take a HUGE battery battery bank to run a space heater (and really would not be practical because of recharge time). Even the electric blanket would require a fairly large battery bank if you are trying to run this while dry camping. Again, look at the watt rating of whatever you are wanting to run.

Christod, What is your engine serial number? I can call my contact at Caterpillar Corp to determine whether you can fit an effective exhaust brake (i.e. high back pressure brake) without fitting the stronger valve springs. And, yes, to descend a hill with any rig-- gas or diesel, use the transmission to gear down to a gear that holds your speed in equilibrium. If you don't have an exhaust brake on your diesel, you can do this (though far less effectively) by using the down arrow on your Allison shift pad. If you can fit an exhaust brake (depends on engine serial number), particularly a PacBrake PRXB, it is VERY effective. And, I will repeat-- the safe speed of descent is that speed where you are neither speeding up nor slowing down on a long descent-- I call it your equilibrium speed. It is often NOT related to whether the road is straight or with lots of curves. A good reference is 18 wheelers. Your equilibrium speed will be faster than a loaded 18 wheeler and slower than an empty one.

When did you get your Invisibrake? We had one of the prototypes installed two summers ago. We had the same experience. Roadmaster replaced it this last summer in Madison at the FMCA Convention-- It works perfectly. We now have 5,000+ miles towing with the new brake and it is working just as it should. So, it is possible that you have one of the early prototype brakes. Even the look of the compressor unit is very different. Brett

DEF is available in most truck stops, at Walmart, etc. Here is a list of the Flying J's with DEF right at the diesel pumps: http://pilotflyingj.com/pump-def Brett

Herman, The Caterpillar 3116 can be equipped with an exhaust brake, not an engine compression brake (same as Cummins B and C engines-- only large-displacement engines are generally fit with engine compression brakes). Prior to engine production of fall 1992, valve springs would only accommodate a low pressure exhaust brake. After that, they would accommodate a much more robust exhaust brake. Same thing occurred over at Cummins at this same time. That is why I asked for engine serial number. The exhaust brake is wired through the Allison TCM so that when the exhaust brake switch is ON and throttle closed, two things happen. The transmission begins shifting TOWARD, REPEAT TOWARD the pre-select gear (generally 2nd or 4th but can be any gear you want-- I had mine changed to 5th). It drops one gear at a time as soon as it would not overspeed the engine in that next lower gear. At the same time, the butterfly in the exhaust brake closes, creating back pressure that the engine must work against-- kind of like stuffing a giant potato in the tail pipe. If, for example you have a 2nd gear pre-select, it does NOT downshift to 2nd if you are at highway speed. And, if you are at a stoplight and look at the shift pad and it says "6" you are not in 6th gear, that is the gear the transmission will shift to as conditions permit. Here is another discussion on this subject: http://community.fmca.com/topic/665-exhaust-brake-vs-retarder/ Brett

Christod, Well, I had better open the back of the coach and have a visit with my 3116-- it had no idea it was suppose to have issues at around 80,000 miles. Current mileage is 158,000 miles with no failures. And, the 3116 is rebuilt the same as a Cummins B engine. As with any engine, maintenance over the years is an important determinant of engine life. If your valves have not been adjusted and injector timing set in 19 years, they might be correct-- the engine may fail. But, that would be the same on any engine-- do the recommended maintenance and they will last a LOT longer. BTW, you should join the Caterpillar RV Engine Owners Club (an FMCA Chapter): http://catrvclub.org/ Brett

Christod, Your 3116 has a governed RPM of 2600. 2500 is toward the high end, but certainly not over the redline. I would suspect that your Allison is programmed to NOT allow engine RPM to exceed the 2600 figure. Are you sure you don't have an exhaust brake? If not, what is your engine serial number. Beginning with engines produced the fall of 1992, the Caterpillar 3116 was fit with stronger exhaust valve springs that allowed the use of a very good exhaust brake. Generally, the exhaust brake and transmission downshifting work together when the exhaust brake switch is turned on and the throttle is closed.

One other observation about air dryers. From a cost standpoint, FACTORY reman air dryers are a good, safe way to go. Repeat FACTORY (as in the company that made them), NOT someone else who rebuilds them, perhaps using overseas parts of dubious quality. I have seen examples when working with Bendix of poor quality aftermarket dryer rebuild parts. Brett

floteb1, The Roadmaster Invisibrake comes on only when you step on the coach brake pedal, so use of the Jake Brake will not apply the toad brake. That was a requirement when we looked at systems, as I want the engine brake separate and the toad brake only engaged when I apply my coach service brake.

I agree with Sundancer. Do not change to a silicone-based fluid. Ford has one of the best brake fluids compatible with your system with a new boiling point right at 500 degrees F. Brett

Bill. Welcome to the FMCA Forum. The first thing we have to determine is exactly what suspension you have. If the B.F. Goodrich Torsilastic Suspension (aka Velvet Ride), discussions about air bags would be moot. If that is what you have, the first thing you need to do is check ride height. Shims are removed to raise ride height. Ralph Andrews, owner of http://www.pioneermetalworks.com/ is very knowledgeable about the Torsilastic suspension and has several upgrades for it, including double shock mounts for the front. Brett

As Bill said, very likely the dash A/C condenser. Trace one of the lines from the evaporator (under "hood") down and see if it goes to it. Brett

What chassis? Your chassis maker fit your gauges and air pressure senders, so that is your first point of contact.

jiffyjet2 is absolutely correct. Since front overhang is dictated by steering geometry/driver's position and rear overhang is dictated by length of drive shift, transmission, engine and in some cases the CAC and radiator, to turn a 40' coach into a 30' coach, virtually the whole 10' is taken out of the wheelbase. So almost by definition, the shorter the coach, the poorer the WB/OL (Wheel Base to Overall Length).

Yes you can use that to fill tires and any other things while parked that require compressed air. If the coach did not come with a hose attached, be aware that there are at least three different chuck styles, though they look similar. I would call Monaco and ask what you need to buy to connect to that chuck that they installed. Brett

Start by verifying 12.0-14 VDC at the TWO transmission fuses in your chassis fuse box. Like any computer, low voltage due to bad battery, discharged battery, poor or corroded connection, etc can cause some peculiar issues. Next, query your Allison for diagnostic codes using your shift pad. Instructions in your Allison manual or here: http://www.allisontransmission.com/servlet/DownloadFile?Dir=publications/pubs&FileToGet=SA3360EN.pdf Also, a good idea to unplug and securely replug the two gang plugs at the Allision TCM and the shift pad. Though it does not fit your specific issue, be aware that if the idle speed is too high, the transmission will NOT go into gear. So, high idle speed/idled up speed for warm up is (and should be to protect the drivetrain) an automatic shift inhibit. Brett

Thanks for those great photos. A poster child for the importance of keeping the CAC/radiator clean. By the time it gets as bad in the photos, it is almost a certainty that you will have to pull them to get them clean. If cleaned regularly, you can usually clean with a garden hose from back AND FRONT. Brett

I agree with Roger-- the majority of tire failures are NOT due to material or workmanship issues. This is particularly true of the smaller tire sizes (i.e. 235 and 255/80R22.5), since these sizes have lower carrying capacity than larger tires, so they are much more frequently overloaded and/or run underinflated. They were generally chosen to save the chassis maker a few bucks, NOT because they were the best choice. BTW, our coach has over 158,000 miles, all on Michelin tires without a single failure. But, I have seen coaches weighing 8,000 pounds more on the same tires! Brett