Changing Rear Axle Ratio?
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Changing Rear Axle Ratio?
I have a 99 F250 XC 5.4L 4x2 Auto with a stock 3.73 rear end. I do very little hauling and really do not use the vehicle to capacity. I am thinking of going with a higher(lower number) gear ratio for gas mileage. Does anyone have any experience with higher ratios?
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Changing Rear Axle Ratio?
[font size="1" color="#FF0000"]LAST EDITED ON 17-Oct-00 AT 09:26 PM (EST)[/font][p] I have a '95 F150 with the 5.8 and a 3.55 gear. I wish had the 3.73. I only tow 3-4 times a year, but I miss the extra "umph" the lower gear would give me.
Changing the gear would be costly and I don't think you would notice all that much difference in performance in your daily driving. You have a great set up in a truck. My 2 cents worth: keep your truck the way it is. You never know, that lower gear might just come in real handy sometime. If you are worried about mileage, try a K&N air filter or even a powerchip. Many people claim these little tricks help boost their engine's performance/efficiency and make driving more fun. As far as fuel economy, the difference between the 3.73 and 3.55 would be nominal. Hope this helps.
Changing the gear would be costly and I don't think you would notice all that much difference in performance in your daily driving. You have a great set up in a truck. My 2 cents worth: keep your truck the way it is. You never know, that lower gear might just come in real handy sometime. If you are worried about mileage, try a K&N air filter or even a powerchip. Many people claim these little tricks help boost their engine's performance/efficiency and make driving more fun. As far as fuel economy, the difference between the 3.73 and 3.55 would be nominal. Hope this helps.
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Changing Rear Axle Ratio?
Remember, the SD tires are larger than an F150. So the SD with the 3.73 rear end is about the same ground ratio as an F150 with a 3.55.
Given that the SD weighs quite a bit more than the F150, I don't think you'll want to go to a lower ratio.
If your doing local or country driving on 2lane higways in traffic, (less than 50mph or so) your tranny will rarely get into OD, which will probably result in lower mixed city/highway mpg..
Given that the SD weighs quite a bit more than the F150, I don't think you'll want to go to a lower ratio.
If your doing local or country driving on 2lane higways in traffic, (less than 50mph or so) your tranny will rarely get into OD, which will probably result in lower mixed city/highway mpg..
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Joined: Aug 2000
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Changing Rear Axle Ratio?
If it were me, I'd try one of those add-on overdrive units. I'm not sure what they cost, but it would probably cost around $1000 for someone to change your rearend gears. I think the overdrive would be a more versatile addition.
http://www.eurekaboy.com/f250.htm
http://www.eurekaboy.com/f250.htm
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