Ray Pickle

D.I. fuel delivery is employed in over 55% of powertrains presently produced. The real issue of intake valve carbonization is a simple matter of understanding the need to change old ways/habits as it relates to maintenance. Use appropriate chemicals at appropriate intervals and the likelihood of having to deal with worst case scenario of manual valve cleaning is minimized. Pretty much like everything else related to vehicle maintenance.

And then there are the dyno differences etc. Sometimes agenda driven by operator?

Way underpowered may be a bit of a stretch. 400 c.i.d. and 401 hp/464torque, vs 7.3 - [email protected] 430hp/475torque. Based on numbers looks like 7.3 is a little weak for displacement. Not to be biased lets include the old and vaunted, GM 8.1- 496cid @ 345hp and 450 torque. Could they tune for more power especially with more octane, I am certain. But for maximimum reliabilty and commercial applications it was primarily intended for I think the numbers are pretty solid on regular gas. The 10 speed will bring its towing performance equal to 7.3 and it gets better fuel efficiency with the old 6 speed so I expect that will also marginally improve further beyond the Ford.

So the difference appears to be about $9700? Slightly less than previous years, maybe because of the 10 speed in the gasser?

Defining " battle tested", may require more than one or two examples of just 100k. That being said I have minimal concerns that the 10 speed will be problematic based on other versions already in service.

I have a 20' 2500 and it does not lock out 6th gear. In tow/haul it rarely upshifts to 6th gear but it will under low load with speeds of 60 plus mph, "slight downhill", also agree that 5th is preferred cruising gear and the one that truck stays in on relatively level ground.

Agree with everything you said, my general message though is, the powertrain is being artificially limited. The why is speculation until otherwise proven. What you posit may well be true it just hasn't officially been explained. My truck WILL pull at or near redline up that exact pass if I choose to beat it that hard. I do think gearing between existing 2nd 3rd and 4th gear would improve tiwing experience under thise extreme conditions. That being said if the engine is outside its emmissions envelope and won't exceed 2400 to 2500 rpm when stressed, the transmission won't matter either way. The engine is operating under peak torque and significantly under peak h.p. It seems to me that combustion temps and trans temps would both be negatively impacted in that artificially created, "low rpm high demand scenario.

TFL does what they do for uniformity not a fan of some of their dialogue but understand why they do that. The truck will climb long grades at high altitide at high rpm without overheating trans or coolant I have done it many times. Are there emmissions issues that just affect G.M. engines but not Ford gassers in that narrow circumstance thus causing a tuning adjustment that disallows downshifts to the proper gear for that circumstance? Possible/Maybe ? its beyond my purview. But to say " they have trouble on long grades and will only do 2400 rpm". is nonsense. I questioned the validity of the reasons for poor tuning being told it was due to poor thermodynamics/heat dissipation of l8t in that other thread and got nowhere regarding specifics other than I probably couldn't understand the subject matter well enough to follow along.

I don't recall my truck ever downshifting while in tow haul to 5k. Frankly I don't think it downshifts far enough at hwy speeds during deep descends to maintain desired speed. Example, if I have crested a hill and it is 5-6% down for the next mile plus and I am at 65mph the truck only downshifts to 4th gear in an attempt to hold speed. Often speed increases and a downshift to 3rd is no longer an option even on manual mode. If I am concerned about the length and steepness of the decline I typically slow to about 50 or 55 and manual go to 3rd gear beginning descent. Rpm's are higher but truck is in control of trailer and brakes are cool if needed.

I drive a little slower most of the time, around 62 mph. I do not use cruise control in anything but predominatly flat terrain for that exact reason. I pickup speed on downhills, maybe up to about 67- 70 mph, whatever existing steady pedal pressure achieves within reason, anticipating bleeding speed on uphills. Much more efficient than losing 3 or 4 mph while climbing before downshift and then attempting to regain lost speed while climbing.

Couple of comments hear desiring 4.10 gear along with 10 speed. Frankly the need for 4.10 is greater now with 6 speed. 10 speed has deeper gearing and the benefits of lower axle ratio are greatly reduced, not to mention poorer mpg of lower gear offsetting potential gains from trans.

I agree to consider non- tow haul at your weight the truck will pull in 6th gear far more often which may improve your mpg. I would be curious of your results, please let us know if you try it. I'm such a frugal bastard I will turn tow-haul off whenever conditions allow to maximize mpg with a 12k fiver! Any sustained downhill grades or hills that it can safely be executed, or on level ground- slight inclines with a tailwind!

Is your truck pulling in 5th and occassionaly in 6th gear on flats to 2% grades? If not something isn't right. Do you lock out top 2 gears and pull in 4th to keep revs up? If so that would account for poor mpg. Iam at a loss otherwise for poor towi ng mpg. I can maintain speed on level ground up to 2% grades in most instances in wither 6th or 5th gear. Rarely do I downshift to 4th and rev to 3k range unless terrain is more hilly or headwinds. Check trailer brake adjustment, tire pressures on both?

Was that stop and go in town for a significant % of the tow? Possibly high headwinds or front quartering winds? That is low mpg for what you are pulling if your speeds are 65 or less. I average that pulling a 12k 13.5 ft tall fiver in the west and a little over 9 in the midwest. I acknowlege a fiver has better aerodynamics than a travel trailer but your shorter length, less height, and weight should more than make up for that.

Late answer- they clearly did not reset your o.l.m. I personally would do 5k on that oul and then follow o.l.m. moving forward. Obviously and unfortunately you need to check that they reset it!