Downshifting on downgrades April 28, 2020, 10:12:41 am Hi all, In preparation of my trip from AZ to WI I have been reviewing driving techniques for some of the grades we are sure to encounter. I am familiar with driving a stick shift car so the idea of changing gears isn't foreign to me... but trying to wrap my head around the idea of shifting into 2 and 1 to deal with declines. (somehow the inclines seem to make more intuitive sense to me).I do get that the decline gear should be equal the gear it took on the incline. I've been watching you-tube videos but am more than open to suggestions if there are specific ones you recommend.Here are my questions:When going down hill and using the engine to slow you down - are you using the gas at all or basically coasting? If I pull out to rest on the downhill - instead of starting in Drive - can I just begin in the lower gear that I anticipate needing?Is there a max rpm the engine should be in... ie say I am going downhill in second gear (i imagine the engine will sound whiney) but the rpms are to high... is this when I switch into first? When you do downshift, is there a method ie speed up a few mph then release the gas to coast and then shift? Or do you just shift. (say you are driving on a flat in Drive, then come upon a downhill and need to shift from D to 2). Ive been seeing other forum posts talking about transmission temp instead of... whatever the normal temp gauge is on the dash (engine temp? radiator temp?) is this something else I have to worry about?Thanks in Advance!! Jodi 2 Likes
Re: Downshifting on downgrades Reply #1 – April 28, 2020, 10:49:27 am Install a scan gauge ..you can monitor the transmission fluid temp..as well as ..the water temp in degrees.also can display RPMs...my dashboard temp gauge is not as accurate as my scan gauge..For instance my scan gauge will display 200 degrees for water temp..but my dash gauge will read below half
Re: Downshifting on downgrades Reply #2 – April 28, 2020, 11:38:07 am Any time I attack a long down hill grade, I try different combinations of gears to get to a point where there isn't much braking and I'm comfortable with the speed. To start out, I might turn off overdrive then go down to 3rd and 2nd if it is steep and long, all to achieve not having to brake much. I have a lot of miles on mountain roads with many different vehicles and this always works for me. Keep in mind, our motor home has an old school transmission so this may be different for others. Keep an eye on the RPM's and use that as a gauge when to brake some to get them back down. The lower the gear, the higher the RPM.Jon 1 Likes
Re: Downshifting on downgrades Reply #3 – April 28, 2020, 11:47:03 am Jodi, your 2000 has the 4R100 4-speed transmission with 'button-activated' overdrive and no tachometer; the first 'two haul' transmission appeared in the E450 with the 2005 model, and the tach in the 2004.I have a 2003 23.5' (and don't tow), but I can describe what I do when 'upping and downing' (which is a lot of the time!); others with the same transmission may offer different/additional advice, but these methods have worked for me for 118k miles. Your rig is heavier from the get-go, but I believe that the techniques are still applicable.The 4R100 transmission lags and 'hunts' for the appropriate gear; its ratios are "2.71-to-1 for first gear, 1.54-to-1 for second, direct 1.00-to-1 for third and 0.71-to-1 for fourth." It's not a 'tight' transmission, and without a tach, you will rely on the sound and the 'feel' of the transmission to learn when to shift. I do agree with the advice to install a Scan Gauge or similar; you may choose to do this at a later time, but for your trip back, a few suggestions:Safe driving of steep grades, especially in a large, heavy vehicle, requires a driver to go down the mountain at (roughly) the same speed and in the same gear(s) as s/he drove up, and to use the brakes sparingly, if at all, while descending. If the downhill speed requires frequent braking to maintain a safe downhill speed, slow down and use a lower gear to descend; avoid overheating the brakes! Save the brakes for emergency situations.If your vehicle has an automatic transmission, click off the overdrive! (It’s advisable to take the transmission out of overdrive on the uphill pull, too.)Shift the transmission into the appropriate gear before descending, i.e., at the top of the grade, whenever possible. When the grade is steep (8%-9% or more!), (or) the road surface is rough, the lanes narrow, and/or the curves are frequent and/or are of the 'hairpin' type, descend in (first or) second gear. Many lesser grades also require using lower gears to descend safely if the road surface is poor or the road is curvy and/or narrow.If the transmission isn’t already in a lower gear, drop to about 20-25 mph before shifting into second; it’s unlikely that you should be going much faster than this anyway if you’re driving the conditions described above!If the grade is super-steep, e.g., 10%-12% or more for any distance, shift into first gear; reduce the speed to about 10-15 mph before shifting into first gear.Brake before going into a curve, not in mid-curve. If necessary, knock off about 5 mph of speed before each curve by 'stab braking' (lightly but steadily applying pressure) before going into each curve; if you have to brake while in or going out of the curve, you’re going too fast for conditions.Don’t ride the brakes! Allow the correct gearing to help keep the vehicle at a safe speed. (Never 'pump' ABS brakes; pumping can lock them up. Apply light, steady pressure.) Smoked brakes are not a good thing!Listen to the engine; (If the new-to-you rig already has a ScanGauge or other, watch the rpms.) If the engine is "protesting", you're going too fast for the gear choice (and probably too fast for the road conditions); slow down and adjust the gearing and speed to conditions. The engine should sound about the same when going up and down the mountain.Use your mirrors, including the passenger side mirror, constantly; be aware of whatever might be coming at you from behind on the passenger side of your rig!Don’t allow drivers behind you to push you into traveling at unsafe speeds or performing a risky maneuver! Pull over and allow faster traffic to pass only if and when there is a safe place to do so! Try to spot possible "safe", i.e., wide enough, long enough, available space, appropriate surface, pull-outs in advance; stay aware and "drive 15 seconds ahead and behind"! Use the turn signal and slow down before heading into a pull-out; don’t damage yourself, your passengers and/or pets, or your rig by pulling over when it’s not safe.Understand that you will be sharing the road with many folks whose driving skills and decision-making capabilities are no match for their egos, especially when driving mountain roads. Let them pass when it’s safe for you and your rig; you’re likely to catch up to the road racers when they jam on their brakes at the next curve or when they have to slow or stop for a construction zone! Have a good trip. 21 Likes
Re: Downshifting on downgrades Reply #4 – April 28, 2020, 12:53:49 pm Quote from: Gwar44 - April 28, 2020, 10:49:27 amInstall a scan gauge ...Is it correct to say that the ScanGauge II (ScanGauge - SG2 II) is basically the one and only such device that can and should be used to monitor i. e. the transmission fluid temperature on our Ford V10 engines? Or is there also some Bluetooth device available that works with iOS (and displays all the temperatures)? I would prefer something without cables.Klaus As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Downshifting on downgrades Reply #5 – April 28, 2020, 01:24:04 pm Lots of good information here.To monitor the transmission temperature in our 2003 LD, it use as ScanGauge II. This model has the ability to be programmed to monitor the transmission temperature. The standard ScanGauge doesn't. Our ScanGauge also is used to monitor the engine RPM, useful on up and downgrades.» ScanGauge IIMany have an Ultragauge, another OBDII scanner that can show a huge amount of information, more than what 99% of us need to know. Both of my Jeeps have Ultragauges and I find the ScanGauge easier to use, definitely a YMMV situation.How to use the ScanGauge. When climbing or descending steep grades, I keep the engine speed around 3800-4100 RPM, it seems high and makes a lot of noise but the engine is designed to run at those speeds all day long without damage, thanks to the overhead cams. Take advantage of the engine high potential speed, this engine was not designed to be babied .Truck engines are designed to run at full throttle for extended periods without damage, unlike car engines, the engine's computer (ECM) prevents over-reving.The transmission is a durable unit with a good size cooling system, overheating is not common, especially when not towing.The instrument panel does not have a transmission temperature gauge, the reason why so many owners install auxiliary gauges, such as a ScanGauge. It's easy to install an OBDI (On Board Diagnostics I) gauge, plug it into the OBDI port under the dash on the driver's side, and place the gauge on the dash or steering column, secured with Velcro.It's a good idea to monitor its operating temperature when climbing long upgrades. The transmission should normally run between 180-210 degrees, less on cool days. When climbing on hot summer days, burst to 230-235 degrees is acceptable as long as it cools off once the road levels or heads downhill. The transmission was designed for this use and is not abusing it.Driving a lightly loaded LD, without a toad, isn't much different than driving a large car, once you get used to its wide width.The computer will take care of shifting on level ground and upgrades, only needing to be manually shifted to a lower gear on downgrades. Second and third gears are the ones most often used in 4-speed transmissions for climbing and descending.Larry 7 Likes
Re: Downshifting on downgrades Reply #6 – April 28, 2020, 01:24:21 pm Quote from: Klaus - April 28, 2020, 12:53:49 pmIs it correct to say that the ScanGauge II (ScanGauge - SG2 II) is basically the one and only such device that can and should be used to monitor i. e. the transmission fluid temperature on our Ford V10 engines? Or is there also some Bluetooth device available that works with iOS (and displays all the temperatures)? I would prefer something without cables.KlausKlaus, the answer to your first question is NO. I have and used to use a ScanGauge II. I now use an OBDLink MX+. OBDLink. It is a Bluetooth OBD adapter. They have both iOS and Android apps.Charles 1 Likes As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Downshifting on downgrades Reply #7 – April 28, 2020, 01:36:53 pm Joan really said it perfectly; don't be too affected by what the drivers behind you are doing. I believe that many times they are people that have never driven anything large or heavy. They don't have any empathy for the complications of having so much weight, length, heigth to control at speeds. Especially in non optimal weather, road conditions. I think many times those other drivers are commuters who routinely know every twist and turn of the road ahead, and don't consider that someone may be new to that road. (or vehicle). RonB 4 Likes
Re: Downshifting on downgrades Reply #8 – April 28, 2020, 01:43:06 pm This article from The Lazy Daze Companion (another valuable resource for you to study), may help. The Lazy Daze Companion: Transmission 1 Likes
Re: Downshifting on downgrades Reply #9 – April 28, 2020, 01:55:08 pm JodiSafe driving of steep grades... requires a driver to go down the mountain at (roughly) the same speed and in the same gear(s) as s/he drove up, and to use the brakes sparingly, if at all, while descending.Joan is spot on! I don't know when I've read that technique offered so succinctly.I learned to drive under the tutelage of my Professional, Over the Road, truck driving Father. He was the best gear jammer I've ever known. When it comes to down shifting on a grade the answer is in my blood and I do it instinctively. 4 Likes
Re: Downshifting on downgrades Reply #10 – April 28, 2020, 02:04:41 pm Is a Scan Gauge the only device?I ran a Scan Gauge for several years until my eyes could no longer focus on the tiny display. That's when I switched to the Ultra-Gauge and haven't regretted the choice. UltraGauge OBDII Scan tool & Information CenterCaviot: The Ultra-Gauge has a steep learning curve so it is best to start when you have plenty of time and concentration to understand how to program and use it to best advantage. 1 Likes
Re: Downshifting on downgrades Reply #11 – April 28, 2020, 02:20:16 pm "The computer will take care of shifting on level ground and upgrades..."----The computer does shift down on upgrades - eventually. But, for me, the extended 'lug down' when uphilling is usually delayed, so I kick off overdrive (if it's not already off) and downshift manually if the climb calls for it. I do have a Scan Gauge, but I still rely on sound and engine 'feel' rather than looking at RPMs for the right gear; with the 4R100, one doesn't have many choices! (And, I still foot stab for the clutch and reach for the floor stick!)Always a YMMV situation, for sure! 1 Likes
Re: Downshifting on downgrades Reply #12 – April 28, 2020, 03:06:32 pm Quote from: Klaus - April 28, 2020, 12:53:49 pmIs it correct to say that the ScanGauge II (is basically the one and only such device that can and should be used to monitor i. e. the transmission fluid temperature on our Ford V10 engines?Or is there also some Bluetooth device available that works with iOS (and displays all the temperatures)? I would prefer something without cables.I prefer the dedicated hardwired monitors, they are more stable and require less fussing with. I own a couple of Bluetooth OBDI monitors and apps and I can't say I was impressed with their ease of operations.A ScanGauge is small and doesn't take up much room.Bluetooth scanners will need the phone or tablet to be turned on and set to the OBDI program, using the phone for other functions at the same time is problematic.Larry
Re: Downshifting on downgrades Reply #13 – April 28, 2020, 03:26:33 pm Quote from: Joan - April 28, 2020, 02:20:16 pm"The computer will take care of shifting on level ground and upgrades..."----The computer does shift down on upgrades - eventually. But, for me, the extended 'lug down' when uphilling is usually delayed, so I kick off overdrive (if it's not already off) and downshift manually if the climb calls for it. When hear and feel the engine slowing on upgrades, the pushing down on the accelerator for a moment will cause the transmission to downshift, even when using the cruise control. I manually downshift the transmission if it is 'hunting' between gears or when descending. Once it has downshifted, the transmission tends to stay in the lower gear until the grade flattens,The 4L100 transmission has the third gear downhift button on the end of the turn signal stalk, my right index finger automatically pushes it when needed. After driving LDs for 180,000 miles, what to do when climbing and descendings has become a reflex. If you eventually pull a toad, you will need to become more vigilant when descending steep downgrades, a situation that can get away from you very quickly if not using the correct low gear. With 18,000-lbs pushing downhill, excessive speed can build in just seconds. Larry
Re: Downshifting on downgrades Reply #14 – April 28, 2020, 03:58:17 pm "If you eventually pull a toad, you will need to become more vigilant when descending steep downgrades..."---I figure that this refers to Jodi; you know that I have no plans to tow! I just hope that I remember how to drive when I can get loose again! 4 Likes
Re: Downshifting on downgrades Reply #15 – April 28, 2020, 04:58:23 pm Jodi, I love what Joan and Larry had to say. They are spot on. I drive the western states, towing a Subaru Forester. All I will add are a few real life examples. First, on I-5 northbound from California to Oregon, the Siskiyou grade is a LONG, moderately steep grade. I drop into 2nd at the top and brake a few times, when RPM's reach 5000, descending at about 25 to 30 mph in the right lane. If memory serves, I would have to use the brakes twice, each time slowing from 5000 to 3000 RPM. I try to stay in that range.Second, on Rt 160 in Colorado, heading southwesterly toward Pagosa Springs, there is a long, steep grade. I dropped into 1st gear at the top. Periodically, I would have to brake to drop RPM's below 5000. At 3000, I would release the brakes and coast. One third of the way down, my transmission temperature had climbed to 225, so I pulled into one of the turnouts, put the transmission in park, left the engine on to keep coolant flowing, and waited until my transmission temperature dropped below 200. I repeated this at about 2/3 of the way down. If I had braked often to keep the speed down, rather than the way I did it, I would have lost my brakes and been out of control before reaching the bottom.Third, Rt 22 between Victor, ID and Jackson, WY has the Teton Pass, a relatively short but steep and winding grade, particularly in the eastbound direction. I drop into 1st gear at the top. I do the usual braking as needed to stay below 5000 RPM. It takes 5 or so brake applications before I am down.When I brake, I use medium braking force, with a steady pressure until my RPM's drop to where I want them. I do not pump the brakes, I do not "stand" on the brakes, nor do I use the brakes gently. I want to use enough brake pressure to drop quickly to my desired RPM's so I can release the brakes.The key to remember is, keep your speed under control, anticipating how to do that, so you are NEVER in the position of saying to yourself, "OMG I am going too fast for this road". Plan the use of gears and brakes so your worry is for your engine, transmission and brakes, not for control of the rig.Ken F in NM 4 Likes
Re: Downshifting on downgrades Reply #16 – April 28, 2020, 05:14:16 pm Quote from: Larry W - April 28, 2020, 03:06:32 pmI prefer the dedicated hardwired monitors, they are more stable and require less fussing with. I own a couple of Bluetooth OBDI monitors and apps and I can't say I was impressed with their ease of operations.A ScanGauge is small and doesn't take up much room.Bluetooth scanners will need the phone or tablet to be turned on and set to the OBDI program, using the phone for other functions at the same time is problematic.LarryTo each his own. I would really prefer aftermarket dedicated mechanical and electro-mechanical gauges like I installed on most of my older vehicles but didn't want all those cluttering up the dash in our LD and having to install senders, sensors, and all the associated wiring.I started using a ScanGauge II that I already had. I got fed up with having to send it (and my original ScanGauge) in for updates and programming them to read transmission temperature was a pain. I also don't care for the display. I bought a cheap OBDII Bluetooth dongle that was fine on my Acura and Scion but had problems with the E450.I then bought an OBDLink MX and paid for the Ford update. Worked fine. Then I found the OBDLink MX+ on sale and bought one; it comes with Ford support. Updating both of them and the app is painless and quick. I now use the original OBDLink MX in my primary vehicle and the OBDLink MX+ in our LD.I use an old Motorola Moto X (Android) phone linked to the OBDLink MX+ which displays 8 gauges. My Samsung phone is only used as a phone. I also use a Samsung 10" tablet as a GPS mounted in place of the rearview mirror. The Moto X, tablet, and our laptops can all connect to my MiFi by Wi-Fi for cellular access and data sharing so no wires needed.Charles 1 Likes
Re: Downshifting on downgrades Reply #17 – April 28, 2020, 05:47:38 pm "Rt 22 between Victor, ID and Jackson, WY has the Teton Pass, a relatively short but steep and winding grade, particularly in the eastbound direction. I drop into 1st gear at the top. I do the usual braking as needed to stay below 5000 RPM. It takes 5 or so brake applications before I am down."----Teton Pass offers the added attraction of having the runaway truck ramps/gravel pits on the opposite side of the road when descending eastbound! 3 Likes
Re: Downshifting on downgrades Reply #18 – April 28, 2020, 06:32:11 pm "And, I still foot stab for the clutch and reach for the floor stick!"I'll never forget the first time I drove an automatic. I believe it was a Plymouth Fury, late 50's, and it had this extra wide brake pedal. Needless to say, I locked the brakes (long before anti-lock) as I came to a sudden stop. Thankfully, no one was right behind me, but embarrassing to say the least.Rich ex 2000 MB Birch Bay, WA 1 Likes
Re: Downshifting on downgrades Reply #19 – April 28, 2020, 06:40:44 pm Wow!! This is a ton of useful information!! On the eventual "to do" list will be to get a temp sensor / scan gauge of some sort but for this trip I think I will have to go by feel / sound. I do have a couple of questions though...For overdrive - when is this supposed to be used? I have this on my car and never use it. From what I gather - it is NOT to be used on inclines / declines."The 4R100 transmission lags and 'hunts' for the appropriate gear; its ratios are "2.71-to-1 for first gear, 1.54-to-1 for second, direct 1.00-to-1 for third and 0.71-to-1 for fourth."" Are gear 3 and gear 4 "hidden" inside the D-Drive selection? So only gear 1 and 2 are visible and can be selected when appropriate by the driver?Is the gear shifting something I can practice with a few times on the straight away going slowly 20-25 for 2nd / 10-15 for 1st or will that be back for the engine? I would like to get a feel for the reaction before trying to do it on an up / down hill. I suppose I could also try it in my little old honda crv. We are going to stay on interstates so I dont think I will be to worried about people having to go around us. And if so - they can just wait it out Our first climb will be from Phoenix to Flagstaff on I-17, then some inclines / declines east on I-40 to Albuquerque. At that point I will have some hills behind me and will have to decide to go north to Denver on I-25 or continue east/north east on I-335. My preference would be to go toward Denver for the scenery but the drive will be flatter to the east. Any input on the grades coming north out of Phoenix and then east toward Albuquerque? And if I do decide to go north toward Denver - how are the grades on I-25 from what I have read I think max was about 6-7% but I have no real world experience for what that equates to.
Re: Downshifting on downgrades Reply #20 – April 28, 2020, 06:50:49 pm “Teton Pass offers the added attraction of having the runaway truck ramps/gravel pits on the opposite side of the road when descending eastbound! ”Teton Pass, (White Knuckle Pass and entryway to Jackson Hole from Victor, Idaho for those unfamiliar) actually added a new Vehicle Arrestor on the right side of the downhill lane. It consists of an cliff-over-hanging platform with concrete walls on either side and a series of lane spanning heavy cables connected to “giant rubber bands”. While somewhat alarming to imagine having to use it, it has been used several times by overweight truckers and it does the job!Here’s a description of the Arrestor:http://www.dot.state.wy.us/files/live/sites/wydot/files/shared/District_3/TetonArrestor/Whatisarrestor.pdf 3 Likes
Re: Downshifting on downgrades Reply #21 – April 28, 2020, 07:07:54 pm Warren, that’s fascinating; what an ingenious ‘catcher’! Thanks for posting the link !
Re: Downshifting on downgrades Reply #22 – April 28, 2020, 07:35:27 pm A brief word about runaway vehicle ramps and arrestors - The time to decide whether to use one is not when you are without brakes and are going too fast. Rather, make up your mind before starting down that if you find yourself with fading brakes, you will not try to steer your way down, but will go for the ramp. Indecision in this situation is not a good thing.Ken F in NM 4 Likes
Re: Downshifting on downgrades Reply #23 – April 29, 2020, 08:21:50 am "I do have a couple of questions though..."---PM sent. 1 Likes
Re: Downshifting on downgrades Reply #24 – April 29, 2020, 12:32:37 pm Quote from: Charles & Donna - April 28, 2020, 05:14:16 pmI also use a Samsung 10" tablet as a GPS mounted in place of the rearview mirror.That's an interesting place for a tablet. How do you have it mounted there? Permanently, not permanently? I would appreciate to know how exactly you did this.Klaus
Topic: Downshifting on downgrades (Read 904 times)
previous topic - next topic
Topic: Downshifting on downgrades (Read 904 times)
previous topic - next topic