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wildebill308

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Posts posted by wildebill308

  4. Posted · Report reply

    Ran into the same on the 101. We drove the 101 from San Diego to Washington. Doing 55 and suddenly you get curves marked for 35 in a car. I found that my coach tends to push pretty bad in the corners. The speed is marked as you enter the curve so you have no real warning.

    Bill

  9. Posted · Report reply

    What do you consider high EGT temperatures? I was seeing up to 1350 pre turbo. I don't like to run that hot and have it set up to warn me and it is supposed to derate. I have never let it run at those temps long enough to see if it does.

    I am running the Banks Economind Diesel tuner. I seldom run it above the economy setting that is stage 2. I have run in stage 1 which is the basic stock setting to get a base line on EGT temps and boost. I don't see any big increase in EGT unless I run it in stage 6. You should expect to see higher EGT temps as you are adding fuel to get more power. The Cummins engineers that I talked to in Perry this last spring would not state what the max EGT should be. They said the computer on the 5.9 common rail would derate before damage was done. I have talked to mechanics at the local Cummins dealer and they said 1400 for short times when towing on hills. I think that is a little warm for me so I use 1300 as upper limit/warning temp.

    I have seen high EGT with the tuner set to stock settings when climbing hills.

    People who don't have gages are running a risk of having high temperatures and not knowing it.

    Bill

  10. Posted · Report reply

    Charles welcome to the forum. Get your engine serial number and find out the part number for your turbo. You may be able to find one online cheaper than from Cat. there are places who rebuild turbos so you might check on that to if yours is rebuildable.

    "A better way to keep an eye on you turbo is add a pyrometer to watch the EGT."

    I agree completely. There are other times when coolant temperature doesn't tell the whole story. On my travels this summer I had a couple of places where my coach was pulling in 6th on cruise control and hadn't shifted down but I got a warning of high EGT. We were pulling a long grade that wasn't much but it maxed boost and drove EGT temps way up as it tried to maintain speed in 6th. I slowed down a little and dropped into 4th to bring up rpm reduce the load and drop the temperatures.

    Bill

  11. Posted · Report reply

    I wonder what the manufacturers could do if they had the incentive. The engine makers don't seem to feel any pressure to improve the mileage in the motorhome industry as it isn't that big of a market compared to the over the road/commercial market. The only advance in engines is the new Cummins V8. I don't think it would be that hard for Allison to upgrade to at least a 10 speed. The makers could do a lot to streamline the coaches and get better airflow but there isn't anyone demanding that they do it. Well not anyone they are going to listen to.

    Bill

  14. Posted · Report reply

    I have heard of others who drive with the engine brake/exhaust brake/retarder on all the time. It is cutting your fuel mileage. If the only states for your vehicle are power and brake you are missing out entirely on coasting. Coasting is when no power is applied but you are using the momentum of your vehicle to propel you forward, sometimes for very significant distances. I'm not talking about coasting with the transmission in neutral, I'm talking about coasting, simply not applying power, foot off the accelerator. Think about it, I'll bet you don't take your foot off your car accelerator and immediately start pressing the brake pedal. Only in an emergency situation would you drive like that.

    When you are applying power, you are adding energy to the vehicle. If you apply power until you have to brake you are powering the vehicle much longer than necessary, wasting fuel. Taking your foot off the accelerator and having the automatic braking come on immediately turns that power into waste. If you drive in a manner to apply just the power necessary to get you to the next stop sign or signal and then coast to the stop sign you will be taking full advantage of the power you have already applied. When I approach a town I begin coasting to slow from my cruise speed to their speed limit. Easiest when you know the territory and the speed limits but can be done anywhere. I look for water towers or grain elevators as an indicator of a town. My GPS has shaded areas for towns and these show up two miles ahead when in cruise speed so that helps me know when a town is coming up and I'll start slowing down. Sometimes towns or states post reduced speed ahead signs which are helpful for avoiding sudden or hard braking.

    I'm not suggesting that you coast all the way to a stop at the stop sign. No one is that precise in their judgement of the momentum in the vehicle. I am suggesting that you attempt to do that with the hope that only minor braking will be necessary to bring you to a full stop. This has an added advantage with stop lights. If you slow down well in advance of a red light you increase the chance that you will arrive at the light after traffic has started to move. If you can avoid a full stop you avoid the lower, less efficient gears and significantly increase your fuel mileage. Watch carefully and you will see most truck drivers doing this. Roaring up to a stop sign and coming to a screeching stop is something that you hardly ever see from truck drivers.

    In short any time you apply the brakes, you waste energy and energy is fuel. The harder or longer you have to apply the brakes the more energy you are wasting.

    So how do you use the engine brake/exhaust brake/retarder? Mine is always off. I use it when necessary for additional braking. I use it on downhill slopes to avoid overspeeding. See my post above for techniques to avoid or minimize braking on downhill slopes. I use it when approaching a stop sign or signal if necessary but to be used minimally or completely avoided if possible. I use it in emergency stop situations. I watch traffic very carefully and at any sign of congestion or emergency condition I will immediately place my hand on the engine brake switches (I have a 2 stage engine brake) at the same time I remove my foot from the accelerator and place it over the brake pedal.

    I'm retired, driving a large thirsty vehicle, not a race car driver.

    You are right but I will continue to drive with it on. I can with careful use of the accelerator pedal coast as mentioned. You cannot turn on the switch fast enough in an emergency situation. I also use the cruise control about 90% of the time.

    Bill

  15. Posted · Report reply

    Yes I got yelled at because I tried to pump my own fuel. They said it was against the law for me to pump fuel. The fact that they only pump till the pump shuts off the first time should give you better milage on the first tank but widely varying on the next tanks. Perhaps a combination of all the variables led to your low milage. I ran into B50 Bio in Missoula Montana at the Pilot/Flying J they had 4 different diesels on one pump. The B50, red dyed, #1 and #2 for a much higher price. I bought the #2 to not have to deal with possible problems.

    Bill

  19. Posted · Report reply

    Yes the wording is different between the owners manual and the transmission manual. The owners manual calls it a compression brake and the switch is labeled "engine brake" while the transmission manual calls it a retarder.

    I have looked at the exhaust closely when I installed the new muffler there is nothing after the turbo. When I was doing my fluid change I asked and the Allison shop said I had the retarder. I sometimes think I could get better mileage with it turned off as if you lift a little to much it kicks in and starts to slow you. I have gotten use to it and seldom turn it off. I guess I like that extra braking more than the potential mileage.

    Bill

  20. Posted · Report reply

    Don, go have fun. Utah is the only western state I didn't hit this summer. You didn't say if you have the engine brake or the transmission retarder. I have the transmission retarder and when that is turned on and lift on the throttle it will try to down shift to second gear. This is helpful when going down hills or coming up to a stop sign. You don't need to manually downshift going down hill just let the engine slow you down. If it isn't holding enough use your brakes to slow down enough to get into a lower gear. I only had to get down to third a couple of times where it was a very steep grade. You don't have to worry if it starts to go to fast in the lower gear it will up shift to prevent over reving the engine. Then you can apply your brakes to slow it back down. Just do not ride your brakes as they will heat up and you could end up with no brakes. The only negative I have heard about locking it in a lower gear is if it won't hold the speed in that gear and accelerates to where the engine rpm is too high and you can damage the engine.

    Lots of good advice on climbing. I watch my EGT gauge and if it starts to get to high I will manually downshift or if the water temp starts to go up. lots of people talk about climbing steep hills and having high temps but I found the case where it was a gradual grade and the transmission on cruise could stay in 6th but the boost was running 35psi ( flat land it is 12-15psi) and the water temp and EGT was getting to high. I had to slow and drop to 4th for a while till things cooled off then I was able to pull 5th.

    You will find what works for you.

    Bill

  25. Posted · Report reply

    Well the OP hasn't filled out his profile so no knowledge about his coach.

    I self insure I have seen too many claims disallowed. By the time you get done with the fine print on deductibles and what they will pay for repairs. I think if you put the money in a savings account you will come out further ahead. Yes you need a roadside assistance plan aka Coach Net. Yes you need to do all your preventive maintenance.

    Bill

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