Tractorman

@MrMerica, thank you. It is all clear to me now. - John

I agree that there is a good chance there is a problem with sealing. But, headlight housings are manufactured with a vent, usually with a tiny screen covering the vent and usually located in a very inconspicuous place. So, it is possible for moisture to get in under some unusual wet conditions even if the headlight assembly is in good condition. If that is the case, drying the assemblies could be worthwhile. Doesn't cost anything but time. - John

You will need to park your truck in a dry garage for a few hours. Pick a day when humidity is low. Remove the bulbs and set up a fan to blow at an angle into headlight openings. The angle is important because some dry air needs to enter the headlight assembly, evaporate some moisture, and then exit the same hole. It will take a few hours, but it works. If the moisture returns right away, then the lens has a leak. I have used this procedure a couple of times and it works quite well. - John

Just be prepared mentally if your engine goes to 3 cylinder idle at thirty below zero. The first time (and only time) that mine went to 3 cylinder idle, I thought the engine threw a rod bearing from the racket it made. And that was at 18 degrees above zero. I make sure that I step on the brake pedal when I start the engine in cold weather. I use the exhaust brake for faster engine warmup. Much quieter. - John

Many people don't set park brakes. If you are one who does not set the park brake, you are likely to have your foot resting on the service brake pedal while you are starting the engine. That is will probably cancel the high idle feature. I found this out myself accidently. - John

Several years ago I had the same symptoms (brake lights staying on). I had read about the fact that you had only one chance at getting it right when installing a new one. So I took my old one apart and added a washer or two (can't remember) and re-installed it. It is the original brake light switch and is still working fine today. Sometimes technology seems to go backwards - why such complexity in a brake light switch? - John

Thank you for posting the fix for your problem, but I still am not clear on the solution. Did you replace the VP44 and some relays? or just relays. Also, which relays? Thank you, - John

@NorthernDodge, just be patient - you will probably get a reply from some knowledgeable people shortly. Do you have a wiring diagram available? If you do, you may be able to figure out which control module is being affected. Wiring diagrams can be a bit complex, but at least you have a good radio to listen to while you work on the problem. - John

I am another who has logged over 200,000 miles on front brake pads, rotors, and calipers. I replaced the pads and rotors at 215,000 miles just as a maintenance procedure - there was at least another 50,000 miles left on the pads. I am still running the original front calipers, now at 332,000 miles. And of course, I do have an exhaust brake and it gets used every time the truck is driven. - John

@dripley, finally, here is a photo of the label on the B20 diesel pump at Safeway in Molalla, Oregon. Now I have no idea whether the B20 in Oregon is bio-diesel or bio-mass based diesel, so since I have no idea of what I am getting, I think I will quit using the B20. - John -

My question (just curious) is: When you tested the bio-diesel from Ontario, Oregon and took a loss in mpg, was the fuel B5 (the mandated 5% bio-diesel) or was it B20? The reason I ask is because each time I use B20, which is about 30 cents / gal cheaper, I see an improvement in fuel economy. I have seen this mpg improvement over several trips during this last year. Also, @dripleysaid that he experienced an improvement in fuel economy when he used bio-mass diesel. These mpg improvements seem to defy the logic that there is less thermal energy in bio-diesel or bio-mass diesel, so what gives? Something that @dripleybrought to my attention - there is bio-diesel and there is bio-mass diesel. I am assuming that I it is bio-diesel that is sold here in Oregon, but I don't know that for a fact. I am still trying to find out. - John

It is always interesting to see such differences in fuel prices just a few miles apart. Prices for B5 diesel fuel is currently $3.32 /gal at three different stations in Baker City, just 70 miles north of Ontario. Price for B20 in John Day is $3.03 /gal, B5 - $3.40 /gal and for B20 at Safeway in Molalla, Or is $3.00 /gal and B5 - $3.40 /gal at other nearby stations. Safeway only sells B20. It is the B20 in both mentioned locations that is giving me improved fuel economy. You have to remember that I am making my comparisons from B5 diesel (mandated in Oregon) to B20 diesel. I will be monitoring the differences more closely in the future. Was the tested Biodiesel from Oregon B5 or B20? Have you ever tested B20? I think you are comparing Oregon mandated B5 diesel to Idaho regular diesel, so likely we are not making like comparisons being that regular diesel anywhere in Oregon is B5. - John

@Dieselfuture is right on here. Vacuum leaks are easy to overlook. The vacuum pumps are strong on these trucks and can easily overcome a significant leak and the leak will go by unnoticed. Even the HVAC controls will still work. Remember any air that leaks into a vacuum line will discharge that same air into the crankcase via the vacuum pump outlet. @Evan, my truck has about the same miles as yours and two times now I had noticed excessive vapors coming from the crankcase vent and both time it was caused from vacuum leaks. - John

This bio-diesel or bio-mass diesel thing is bugging me. I carefully looked over the sticker today at one of the diesel pumps here in Oregon. All it says is either B5 or B20, so I don't know if it is bio or bio-mass. @dripley, Do you know of any way to get that information? All I do know is that when I use B20, my fuel mileage increases despite the assumed fewer BTU's. I have used B20 several times now and each time fuel economy is very good - towing or empty. - John

Your are correct. But, defrost mode brings in outside air. Any significant moisture from the outside is removed in the evaporator core with the AC running. The dry air then flows across the windshield and mixes with the air inside the cab picking up any moisture available (wet clothes, moisture from breathing passengers, etc.) and then exits the cab via one-way vents usually located in an inconspicuous area. So, there always fresh, dry air flowing across the windshield. Recirc mode just continues to recirculate all of the air inside the cab over and over again. None of the air exits the cab and no fresh air enters the cab. Any moisture that is picked up in the cab can only be removed if the AC is operating and the outside temperature is well above freezing. Once the outside air temperature falls below freezing the AC will operate less frequently so the water that is condensed from air passing through the evaporator core will not freeze and block the air flow. The result is that the air in the cab will slowly become saturated with moisture and at some point can and probably will start condensing on the windows. Once the outside temperature gets well below freezing, it really doesn't matter if the AC doesn't cycle at all when in the defrost mode. Example: outside air temperature is 20 degrees and it is foggy. Even that air that is fully saturated (100% humidity) will be very dry by the time it is heated to at least 120 degrees and reaches the windshield. The air will whisk away any moisture an then leave the cab through the one-way vents. - John

Since you live in a moderate climate, you can probably get away with that. Once you get into moist conditions in below freezing weather, the AC will operate considerably less often and you will probably see windows begin to fog in the cab. You need outside air to keep windows clear. If that yellow piece did come from your heater core, that would certainly restrict the flow. So, hope all is well now. - John

If my memory serves correct, and that is a big if, I think you were cleaning the junk away from the evaporator core since the evaporator core is the next item in the path downstream from the blower box. All of the air passes through the evaporator core and then through the blend door, and then the heater core. I don't think the heater core is accessible for cleaning unless the whole HVAC assembly is removed. You can flog me if I'm wrong.. - John

You cannot get air from the defroster vents with the mode selector in the Max position. The only way to get air from the defroster vents is to select Defrost or select the combination Floor / Defrost. Max air selection will draw air from the cab via the recirculating door position and send that air through the panel vents. The air temperature will be controlled by the blend door position. You can, however, get any temperature of air (from very cold to hot) in any mode (Defrost, AC, Max , Floor, Vent) because that is the function of the blend door. So, if you are getting a reasonable amount of airflow coming from the defrost vents, there really can be only two possible causes for airflow not being hot. One, the coolant portion of the heater core is significantly restricted; or two, the blend door mechanism / ducting is faulty and cannot direct all of the airflow through the heater core. Hope this helps... - John

I think you are going to have to pull the dash. It is sounding like the air flow through the heater core is mostly blocked, unless the blend door is actually broken and blocking the path through the heater core). The blower motor draws air from outside (through the cowling behind the hood) or from the interior of the cab (recirc mode). After that air exits the blower outlet duct, all of that air passes through the evaporator core. All of that air leaving the evaporator core is either diverted around or directed through (or both) the heater core via the blend door. There is no way to clear any air flow blockage in the heater core area that I know of. I am a bit confused because in an earlier post you answered a question about sufficient air flow from the vents. Your answer: Now you are saying "a little heat but no large movement of air"? - John

That's a good question... and I don't know the answer. I fill with bio-diesel (think) on occasion - at a Safeway store in Molalla, Or (in the Willamette Valley) and a busy station in John Day, Or ( small town). I will check the labels on my next fill up. I pulled these definitions from on-line: Biomass based diesel - The U.S. Federal Trade Commission has defined biodiesel and biomass-based diesel to clarify their differences. According to the FTC, biomass-based diesel means “a diesel fuel substitute produced from non-petroleum renewable resources that meets the registration requirements for fuels and fuel additives established by the Environmental Protection Agency under 42 U.S.C. 7545, and includes fuel derived from animal wastes, including poultry fats and poultry wastes, and other waste materials, or from municipal solid waste and sludges and oils derived from wastewater and the treatment of wastewater, except that the term does not include biodiesel.” Biodiesel, on the other hand, means “the mono alkyl esters of long chain fatty acids derived from plant or animal matter that meet: the registration requirements for fuels and fuel additives under 40 CFR Part 79; and the requirements of the American Society for Testing and Materials standard D6751–07b (Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels).” - John

I tried two stroke oil once. The engine was real quiet when I poured it in the tank, but as soon as I started the engine, the noise came back. Actually, living in Oregon I get the benefit of the state mandated 5% bio-diesel at the pump so I have never had the need to seriously try two stroke on a regular basis. If it weren't for the mandated 5% bio-diesel, I know I would experiment with adding two stroke oil. Also, I occasionally run 20% bio-diesel and I have noticed gains in mpg on several occasions (both towing and not towing) which did surprise me a little. - John

@dripley, thanks for the follow up. It is nice to hear the details (the good and the bad) after a repair job is completed. I bet it feels good to have a good performing truck again. And it's quieter. That doesn't happen very often. I just towed my tractor to Baker City and I now have over 241,000 miles on the VP44. I am going to continue to run it until I see or feel a performance problem. Hopefully, it won't leave me stranded. You did leave out one detail, however. You did not tell us what else you use your head for if it is not just a place to put your hat. The details are important. - John

Check for codes using the ignition switch. Turn ignition switch on and off three times. Third time "on", leave "on" and read codes in the odometer. PCM first, then followed by ECM. - John

Hopefully, there is no gas in your tank. Your question about two stoke oil has already been answered in a previous post - see below... - John

My son-in-law has a 2006 Ram 3500 Dually 5.9 Cummins with a manual six speed. The catalytic converter was stolen while the truck was parked for awhile. My question is: Will there be any adverse side effects if the catalytic converter is replaced with a straight pipe? Smog testing is no longer an issue with the truck. From what I know, I don't think it would be an issue, but I would rather hear from others who might know differently. Thank you, - John