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Automatic Better Economy Than Manual
If you plan to do more than very occasional towing with any degree of load; DO get the stick. Automatics of ANY make are NOT up to towing PERIOD, unless the transmission and torque converter are significantly modified. Automatics also reduce brake pad life as compared to a propery driven manual shift.
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Automatic Better Economy Than Manual
The most factual and convincing case for manual transmissions is the trucking industry. They are in business to make money and move freight via the MOST efficient AND reliable means. Nearly all commericial freight trucks are manual transmission. There are a very few smaller freight forwarding trucks out there with automatics but they are the exception. The BIGGEST reason the auto industry pushes automatic transmissions on the public is the 98% of folks out there on the road don't know how to drive much less drive a manual shift transmission. This is the same "logic" used by the military. Pvt. Snuffy can tear up a solid iron ball with a balsa wood hammer. If you could have seen the number of destroyed manual transmissions and burned up clutches laying in the motorpools, you would then understand why Uncle Sammy chose automatic transmissions.
If you want to get a classic deer in the headlights look; try and instruct the typical driver on how to double clutch, how to properly upshift or down shift.
The big problem with automatic transmissions especially when used for towing applications is how long and with how much throttle position the torque converter can hold lock up. No automatic transmission has lockup torque coverter capability is ALL forward gears excluding 1st. There is lies the problem. If you want to demonstrate it to yourself, try hooking up to a 10,000 lb. to 12,000 lb. load and pull it through steep mountain or hilly roads. The transmission will be constantly hunting for gears on long steep grades. The so called "tow/haul" mode just delays the inevitable the converter eventually will unlock and the trans. fluid BBQ begins. I don't care how many trans. oil coolers you have. When I come to a hill I gain speed in anticipation for the steep grade and go for full throttle pedal and hold each gear as long as I can and shift gears at rpms that still allow me to remain in an adequate torque/hp range. This is impossible with an automatic. If you firewall the engine, the transmission will nearly always attempt to downshift to a lower gear. When you let off the pedal to allow the rpms to come down out of the stratosphere, then the engine is not in an adequate rpm range to pull the load. Then the gear hunting starts. I normally get over 22 mpg with my 6 spd. manual Cummins powered Dodge; on ocassion up to 26 mpg. You won't get that with automatic.
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Automatic Better Economy Than Manual
Eric, I don't think it is so much the people in the military as is it the idiots that make the decisions and how we as a nation bring our kids up and how the military trains and conditions them. In this age of a "don't ask, don't tell", "warm and fuzzy - touchy feely" mentality can't really put it on the young folks entirely. It was my experience that most soldiers wanted to do their best and be successful. It was the idiots making the decisions that frustrated them. I guess some things never change. ;O)
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Automatic Better Economy Than Manual
Mark, if your 5th wheel has any amount of weight,your transmission temps must be near off the scale. If I am not mistaken, the trans. torque converter in your Tundra has lock up capability in OD and 3rd. I doubt that it has lock up capability in 2nd gear. That means the torque convert is slipping against the fluid during the entire climb up the hill and generating phenominal amounts of heat.
To give you some idea of how much heat can be generated. Up until I got fed up with my 3/4 ton 93 Suburban and traded it in on the Dodge Cummins; I used it to tow my Sea Ray. I estimate that the load was somewhere between 9,000 & 10,000 lbs. My Suburban had the HD tow package, 4.10 posi rear axle, the the 4L80E HD auto. trans. I further modified the trans. system with an extra aux. external trans. oil cooler, added a Mag-Hytech double deep oil pan (which doubled my trans. fluid capacity) and ran Amsoil synthetic trans. oil. The torque converter had lock up capability in OD and D (3rd). Just towing my boat 45 miles through a variety of moderate TN hills would heat the fluid up to the point that the transmission would expelled hot oil out of the vent tube. The problem was that the truck did not have the power to hold the torque converter in lockup, nor would the computer allow it even with the chip that boosted engine out put and shift points as well as firming up shifts. The result was that I would either have to gradually back off the throttle in hopes of holding lock up on the torque converter long enough to make it to the top of the hill or as usually happened have to gradually keep increasing throttle to keep any type of minimum speed going up the hill. I would be in 2nd gear doing 25 mph with the throttle to the floor. When I would get home, I had a real nice undercoating of Amsoil synthetic trans. oil on my truck undercarriage and my boat hull. I have NEVER had an issue pulling any load with the Cummins and the 6 speed manual. Even the GM Duramax diesel pickups have this problem with the Allison transmission. GM used to offer a manual ZF 6 speed with their Duramax diesel pickups but stopped doing this early on (I suppose due to the high failure rate). This issue may have been resolved by now. As I said previously, there is NO OEM automatic transmission that comes as OEM equipment offered in the US that is truly capable of adequate towing capacity. You can move up to vehicles over 1 ton capacity but these are not vehicles that the average bear drives.
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Automatic Better Economy Than Manual
Mark, watch your tachometer closely when towing in this configuration. If you watch the tach closely, you will notice the rpms jump up about about 200 rpm without the transmission downshifting to a lower gear as you gradually add more throttle. This 200 rpm jump indicates that the computer has unlocked the torque converter and it is now in fluid coupling mode which generates serious heat. As you add more throttle to maintain road speed, the transmission will eventually downshift to a lower gear and you are correct. This adds to the problem.
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Automatic Better Economy Than Manual
Hydrostatic drive multi-gear range tractor transmissions and automotive automatic transmissions are apples and oranges. Totally different and unrelated working off of different principals.
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Automatic Better Economy Than Manual
Mark, in your case, it sounds to me like you are doing everything you can do to minimize wear and tear. You are pretty much doing what I finally learned to do with my Suburban before I traded it in.
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Automatic Better Economy Than Manual
You got me Eric. Some of those monster logging trucks were powered with everything from a 290 hp Cummins to a Cat 3412 to a Detroit 16V92. Don't know much about them. The guys that were logging our property had an old Osh Kosh powered by an old 290 Cummins. It was a roving oil leak.
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