Mileage and Diff Ratio, Act II
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Mileage and Diff Ratio, Act II
I will be buying a 2000 F-250 XLT ext.cab, short bed, 4x4, V-8, auto this summer and was pleasantly surprised to hear the mileages the 5.4 drivers are getting. My '92 Explorer doesn't hit 15 very often even after I took off all the performance parts.
My question is also about final drive ratio; 3.73 or 4.10. I'm leaning toward the 4.10 as 3.73 came with my anemic 4.0L OHV in the Explorer and the best performance step I took was boosting the ratio to 4.56. I was comfortable turning about 2800 rpm at 75. I think this also brought the vehicle closer to the power curve both around town and on the highway. What rpm are 5.4's turning at 70-75 with the 4.10? Comfortable or does it feel like you're racing the engine? Mileage difference?
My work takes me off road in central NV quite often. Most of the time I'm towing a utility trailer and rarely it gets up to around 4000#s. You can see why I'm having to lose the Explorer though, with the mods, it has been very capable for 126,000 miles. Still aces NV SMOG tests.
Thanks, and any other advise appreciated (all this talk about no steering while on the brakes gives me a little pause...)
Regards,
Bob
Mulepick(No Email Addresses In Posts!)
My question is also about final drive ratio; 3.73 or 4.10. I'm leaning toward the 4.10 as 3.73 came with my anemic 4.0L OHV in the Explorer and the best performance step I took was boosting the ratio to 4.56. I was comfortable turning about 2800 rpm at 75. I think this also brought the vehicle closer to the power curve both around town and on the highway. What rpm are 5.4's turning at 70-75 with the 4.10? Comfortable or does it feel like you're racing the engine? Mileage difference?
My work takes me off road in central NV quite often. Most of the time I'm towing a utility trailer and rarely it gets up to around 4000#s. You can see why I'm having to lose the Explorer though, with the mods, it has been very capable for 126,000 miles. Still aces NV SMOG tests.
Thanks, and any other advise appreciated (all this talk about no steering while on the brakes gives me a little pause...)
Regards,
Bob
Mulepick(No Email Addresses In Posts!)
Senior User
Joined: Jan 2000
Posts: 154
Likes: 0
Mileage and Diff Ratio, Act II
I'm averaging 15.5mpg in mixed driving (city/highway). The OD in the 5sp is a .76 vs OD in the auto at .72. So your numbers might vary.
When I'm at 65 im at 2200 rpm, and 75 im around 2400 or so, but I usally hang below 70.. I think the 4.10 is a great ratio as it does keep the 5.4 in a better power range than the 3.73, allowing more time in OD in city driving and crusing at 55..
Although, if you spend alot of time at 75 mph, I doubt that you'll do much better than 14 or 15mpg.
The engine doesn't seem to be overreving at 65 or 70 and I feel fine cruising at that speed.
When I'm at 65 im at 2200 rpm, and 75 im around 2400 or so, but I usally hang below 70.. I think the 4.10 is a great ratio as it does keep the 5.4 in a better power range than the 3.73, allowing more time in OD in city driving and crusing at 55..
Although, if you spend alot of time at 75 mph, I doubt that you'll do much better than 14 or 15mpg.
The engine doesn't seem to be overreving at 65 or 70 and I feel fine cruising at that speed.
