My truck is a daily driver hardly ever tow anything more than a couple waverunners....and at 70mph I'm turning 2100 rpm. Does anyone make an overdrive unit that would get me into the 1850 rpm range at 70 mph?
My truck is a daily driver hardly ever tow anything more than a couple waverunners....and at 70mph I'm turning 2100 rpm. Does anyone make an overdrive unit that would get me into the 1850 rpm range at 70 mph?
1995 Chevy K-2500 extended cab shortbed, 4L80E, 6.5 Turbo 182,000 miles, 3.73 gear
110K 3" Flowmaster turbo downpipe / 120,000 Heath Diesel PMD relocator kit
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Or usgear.com
97 5spd K2500 Ext Cab short Bed ~160K miles.
TM, 3" downpipe & 4" exhaust, remote FSD, remote oilfilter, Gauges: EGT, Boost, Fuel Pressure, B&W Gooseneck Turnover ball, Prodigy Brake Controller. Hi-Temp Hydraulic Oil Cooler Lines.
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chris maxwell
transplanted to Georgia from the great northwest, and now back to the Evergreen State
1995 GMC ext cab K2500 HD 4:10 gears, 4" exhaust, Kennedy Chip 162,000 miles, Gear Vendor Under Overdrive, rebuilt transmission with trans go shift kit, time for head gaskets....
maxwell9@rocketmail.com
Good Day!
"...at 70mph I'm turning 2100 rpm." Actually, it calculates out ~ 2000 rpm @ 70 mph with your gears & tires.* So, you're already better off than you thought.
A Gear Vendors Aux. OD (0.78 ratio) like mine would get you to ~ 1565 rpm @ 70 mph, which is almost too slow.
What's your issue?
- Noise? Yep, your truck would be much quieter at the lower rpms. If Scotty beamed you into my truck while I'm going 70 mph, you wouldn't know it's a diesel.
- mpg? LLLLOOOONNNNGGGG payback. If you paid $2700 for a GV, get 18 mpg now, figure to get 20 mpg with the GV, & diesel costs $2.60/gallon, it'd take ~ 187K miles to pay for it. (I have a spreadsheet that calculates this for me.) Plus, you're already running just about where you want to be for best mpg. According to the very recent DP article, best mpg is right near peak torque rpm, which is 1800 for our trucks. Soooooo, you might actually not gain much of anything by dropping your rpms this much.
Blessings!
* rpm = (mph) X (1 hour/60 minutes) x (63,360 inches/mile) / (tire dia in inches x pi) X (driveshaft rev/tire rev [axle ratio]) X (0.75 engine rev/driveshaft rev [AT OD ratio])
82 6.2NA K15 4X4 pickup, 4spd man w/ OD, 335K+ "In Rust We Trust" (parked)
95 6.5TD 2500 4X4 pickup, Gear Vendors Aux. OD, > ¼ million miles - gone
95 6.5TD 1500 4X4 3/4T Suburban, Kennedy exhaust, > ¼ million miles
93 6.5TD 3500 4X4 1T crew cab LB pickup, 230k miles