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Old 05-31-2010, 10:47 AM   #29 (permalink)
comptiger5000
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Join Date: Feb 2010
Location: CT, USA
Posts: 544

RaceJeep - '98 Jeep Grand Cherokee (ZJ) 5.9 Limited
90 day: 13.62 mpg (US)
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On my Jeep, I tightened the TV cable on the tranny up a little about a month ago. With the same amount of throttle off the line, it now shifts about 150 - 200 rpm later than before. However, due to reduced torque converter slippage, mpg remained the same, while firming up the shifts a little.

The smaller your engine is, relative to the vehicle, the slower you can accelerate efficiently. With my huge displacement in a 4200 lb vehicle, I can basically idle up to speed barely touching the gas, but it's inefficient. I'm better off getting on it a little harder and letting it shift around 2100 - 2300. If I crawl around letting it shift around 1500 - 1600 (such as being behind slow people downtown), I get significantly worse MPG.
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Call me crazy, but I actually try for mpg with this Jeep:



Typical driving: Back in Rochester for school, driving is 60 - 70% city
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