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slowmover · 12-13-2010, 11:36 PM

The short first gear is to get it moving. Perfect when heavy. And diesels cannot wind up to make HP like a gasser. The rpm range is narrow and the sweet spot only about 200-rpm. I think it no mistake that Dodge made (at least the 3rd Gen) sweet spot for the highway at 55-65 mph, broadly, 58-62 realistically. I use 1,700-1,900 rpm for all miles, town or country (18-20 city, 24-27 highway, solo). Load that baby up with weird gears and you may not like it . . . . hit Ranger Hill west of Fort Worth is only one example, as Texas is the world of wind..

Cummins has on their website a number of tools for business truck drivers. Gearing for highway is different from gearing for city. Gearing for power is different from gearing for economy. Trying to get all four of these -- city versus highway, power versus economy -- together in one truck is harder than it appears. Changing one aspect means worse performance in another. The trade-off may mean great highway mileage, but the performance sucks in commuter traffic. Etc. Just be careful is what I'm trying to say.

Given the age of your truck, the need to see to reliability, and the need to learn to drive it for best effect, spend the first year or so on the above, and maybe play with some of the aero mods being done around here (BamZipPow is a blast to read, as but one of a number of examples. But be careful about the Ford guys, as always

). The tires plus the driver are where the big gains are at first. Truck spec is most important, then climate/topography . . but the difference between all drivers is worth 30%.

The gearing is already good, or very close until your records show the amount of hours/miles broken out for the driving you are doing!! In the end it will be bout gearing and aero. But not in the beginning.

I put economy this way about CTD in posts elsewhere with more detail:

Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Why did I buy a diesel?????

Better MPGs ?? - Dodge Cummins Diesel Forum

Dodge Cummins Diesel Forum - View Single Post - Best MPG possible

Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Is 28MPG possible on a CR?

Thanks for the pics. I was trying to imagine no dash. I have had some really old cars with no dash. But, they practically had no electrics either (about 20' worth in the whole car, not two miles like today).

And, you need at least one pair of vise grips, clamped, sticking up from the dash to give the proper appearance, ha!

.

12-13-2010, 11:36 PM	#7 (permalink)
slowmover Banned Join Date: Oct 2009 Location: Fort Worth, Texas Posts: 2,442 2004 CTD - '04 DODGE RAM 2500 SLT Team Cummins 90 day: 19.36 mpg (US) Thanks: 1,422 Thanked 737 Times in 557 Posts	The short first gear is to get it moving. Perfect when heavy. And diesels cannot wind up to make HP like a gasser. The rpm range is narrow and the sweet spot only about 200-rpm. I think it no mistake that Dodge made (at least the 3rd Gen) sweet spot for the highway at 55-65 mph, broadly, 58-62 realistically. I use 1,700-1,900 rpm for all miles, town or country (18-20 city, 24-27 highway, solo). Load that baby up with weird gears and you may not like it . . . . hit Ranger Hill west of Fort Worth is only one example, as Texas is the world of wind.. Cummins has on their website a number of tools for business truck drivers. Gearing for highway is different from gearing for city. Gearing for power is different from gearing for economy. Trying to get all four of these -- city versus highway, power versus economy -- together in one truck is harder than it appears. Changing one aspect means worse performance in another. The trade-off may mean great highway mileage, but the performance sucks in commuter traffic. Etc. Just be careful is what I'm trying to say. Given the age of your truck, the need to see to reliability, and the need to learn to drive it for best effect, spend the first year or so on the above, and maybe play with some of the aero mods being done around here (BamZipPow is a blast to read, as but one of a number of examples. But be careful about the Ford guys, as always ). The tires plus the driver are where the big gains are at first. Truck spec is most important, then climate/topography . . but the difference between all drivers is worth 30%. The gearing is already good, or very close until your records show the amount of hours/miles broken out for the driving you are doing!! In the end it will be bout gearing and aero. But not in the beginning. I put economy this way about CTD in posts elsewhere with more detail: Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Why did I buy a diesel????? Better MPGs ?? - Dodge Cummins Diesel Forum Dodge Cummins Diesel Forum - View Single Post - Best MPG possible Dodge Diesel - Diesel Truck Resource Forums - View Single Post - Is 28MPG possible on a CR? Thanks for the pics. I was trying to imagine no dash. I have had some really old cars with no dash. But, they practically had no electrics either (about 20' worth in the whole car, not two miles like today). And, you need at least one pair of vise grips, clamped, sticking up from the dash to give the proper appearance, ha! . Last edited by slowmover; 12-14-2010 at 12:07 AM..