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slowmover · 02-28-2013, 02:50 AM

And I found that my rear axle has 3.73 gear ratio which is great for pulling my 700-1500 lb load daily, but terrible for highway speeds.I drive ~200-350 miles per day (including commute) 90% of my daily mileage is rural windy road.

I'd say those gears may not be a problem for those roads. There might be a tendency to push too hard on a vehicle geared too high. Wear on the engine isn't worth it, IMO.

Baseline the vehicle mechanically. No slop in steering, for example. As a tech you know very well it may come down to pulling the intermediate shaft and working outward to the wheels. Everything may need to be replaced. Steering corrections per 100 miles is quoted by truck manufacturers as a measurable problem. MPG, better, fuel efficiency is about the small stuff for a given vehicle with a fixed configuration.

Same for perfect alignment, zero brake drag, and tire pressure according to load (within vehicle manufacturer spec). Weigh the truck, empty, and with at least one sample load (CAT Scale). Work on all the little stuff. And a truck that old may have worn out springs, spring cushions, anti-roll bushings, etc. Best shocks (KONI, second choice is BILSTEIN) make a noticeable improvement. Nose-up ain't acceptable for steering much less for FE.

IMO, it comes down to being able to maintain lane-centeredness with little or no driver inputs on a commercial vehicle (I drive Class 8 in the oilfield, hotshot previously with 1T & gooseneck) or in towing. This is not easy to achieve on an old vehicle. But it's where I'd spend the money. I believe you'll find more money here than in anything else.

My personal truck (in sig) is nearing 200k. The front springs are tired. So are the upper ball joints. So it's time to do it all (this year). Whatever it takes to have a super tight front end and zero-slop steering (though only a guy with concerns about longest vehicle life or highest mpg might notice the difference).

Start with records. Fill out the fuel log. FE is about percentage improvements to the baseline, so records that all can consult about your truck will be helpful.

And, if you haven't bought tires, stick with commercial tires from MICHELIN or BRIDGESTONE with closed shoulder, highway rib configuration.

02-28-2013, 02:50 AM	#42 (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	And I found that my rear axle has 3.73 gear ratio which is great for pulling my 700-1500 lb load daily, but terrible for highway speeds.I drive ~200-350 miles per day (including commute) 90% of my daily mileage is rural windy road. I'd say those gears may not be a problem for those roads. There might be a tendency to push too hard on a vehicle geared too high. Wear on the engine isn't worth it, IMO. Baseline the vehicle mechanically. No slop in steering, for example. As a tech you know very well it may come down to pulling the intermediate shaft and working outward to the wheels. Everything may need to be replaced. Steering corrections per 100 miles is quoted by truck manufacturers as a measurable problem. MPG, better, fuel efficiency is about the small stuff for a given vehicle with a fixed configuration. Same for perfect alignment, zero brake drag, and tire pressure according to load (within vehicle manufacturer spec). Weigh the truck, empty, and with at least one sample load (CAT Scale). Work on all the little stuff. And a truck that old may have worn out springs, spring cushions, anti-roll bushings, etc. Best shocks (KONI, second choice is BILSTEIN) make a noticeable improvement. Nose-up ain't acceptable for steering much less for FE. IMO, it comes down to being able to maintain lane-centeredness with little or no driver inputs on a commercial vehicle (I drive Class 8 in the oilfield, hotshot previously with 1T & gooseneck) or in towing. This is not easy to achieve on an old vehicle. But it's where I'd spend the money. I believe you'll find more money here than in anything else. My personal truck (in sig) is nearing 200k. The front springs are tired. So are the upper ball joints. So it's time to do it all (this year). Whatever it takes to have a super tight front end and zero-slop steering (though only a guy with concerns about longest vehicle life or highest mpg might notice the difference). Start with records. Fill out the fuel log. FE is about percentage improvements to the baseline, so records that all can consult about your truck will be helpful. And, if you haven't bought tires, stick with commercial tires from MICHELIN or BRIDGESTONE with closed shoulder, highway rib configuration.