lifted 4.9?
Freshman User
Joined: Sep 2013
Posts: 27
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Towing might just make me more fond of the engine. I didn't buy mine to tow tho. I wasn't looking for anything fast either. I was just looking for something dependable for day to day driving with occasional light off road use (hunting/winter driving).
Senior User
Joined: Jul 2005
Posts: 101
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Big tires and lift kits look cool, without a doubt. "But", taken to extremes these after=market changes result in problems I moved away from some time ago.
Heavier wheels and tires result in reduced braking efficiency because of the greater weight spinning through the rotors/drums. Radical angles of the u-joints from lifted components causes greater stress and wear on the joints. Excessive lift changes the center of gravity which can be a problem when traversing defiles and slopes. Huge tires can reduce the pounds/square inch, not allowing the tires to cut through heavy slush/snow to get a grip on the road. But we still do it, don't we?
Heavier wheels and tires result in reduced braking efficiency because of the greater weight spinning through the rotors/drums. Radical angles of the u-joints from lifted components causes greater stress and wear on the joints. Excessive lift changes the center of gravity which can be a problem when traversing defiles and slopes. Huge tires can reduce the pounds/square inch, not allowing the tires to cut through heavy slush/snow to get a grip on the road. But we still do it, don't we?
Cranky Old Guy
Joined: Mar 2008
Posts: 3,562
Likes: 6
From: Raphine, Virginia
The torque curve is a key factor. Stock 4.9l reaches peak torque at "roughly" 2000rpm. The closer you are to that in any given gear the better. In high gear for an automatic, 3 or 4 speed, the final ratio is 1:1. Any change in tire size affects the rpm for a given speed. Here is a calculator to play with different gear ratio's: Gear Ratio Calculator
Larger the tires, lower the gears needed to maintain the balance. My "little" six was built entirely for the torque curve, not horsepower. While it does not reach peak torque till 2850rpm, (55mph with 30" tires and 4:11 gears), it varies very little from 1200rpm to 4000rpm. All the other issues to consider when changing tire size, suspension have been mentioned.
Larger the tires, lower the gears needed to maintain the balance. My "little" six was built entirely for the torque curve, not horsepower. While it does not reach peak torque till 2850rpm, (55mph with 30" tires and 4:11 gears), it varies very little from 1200rpm to 4000rpm. All the other issues to consider when changing tire size, suspension have been mentioned.
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