rear end
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From: Shepherd Tx
rear end
Been thinking about changing rear end from 4:10 to 3:55 ,for economy reasons,or would i be better off leaving it like it is and putting a chip in it. I pull a travel trailer sometimes , but not very often and not very far, trailer weighs about 6000 lb. 95 f350 dually stock 19000 miles.Does anyone have any thought on this.
Thanks Jim
Thanks Jim
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Joined: Oct 2003
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From: MICHIGAN
I'm not sure you would notice a significant increase in MPG's, maybe 1-2. It would take a quite a while to recoup the cost of the swap....$5-700 if you pay to have it done.
$1-300 if it's done on the cheap.
If you have an auto trans it may run hotter, towing or not....e4od's already have heat related failures.
My 2 cents.
$1-300 if it's done on the cheap.
If you have an auto trans it may run hotter, towing or not....e4od's already have heat related failures.
My 2 cents.
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Joined: Jan 2005
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From: Brandon, MB
I did switch. I got about 3mpg increase. Depends on how many miles you're going to put on. I see you have a 5 spd as well. I switched 4 yrs ago. Never dissapointed. Mind you, yours is a 4x4. Mines 2wd. easier and cheaper to switch.
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From: Lizton, IN
I always thought I had 4.10's. That's what i was told when I bought it and the mpg's tend to confirm it. I think I run around 2.2-2.30 RPM at 70.
Does that sound right?
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From: MICHIGAN
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From: Lizton, IN
For ballpark gains when not towing...
Lets say it costs 500 to complete the swap to 3.55's and the gain is 3 MPG when not towing, let's say 15 MPG with 4.10's and 18 with 3.55's. Let's also assume $2.75/gallon (who knows what it will do).
(4.10's) $2.75/15 = .183 cents per mile in fuel.
(3.55's) $2.75/18 = .153 cents per mile in fuel.
Net savings in fuel comes to .03 cents per mile. $500 for the swap divided by.03 comes to 16,666 miles before you break even... a year's worth of driving or less to offset the cost. To me that doesn't sound like a good trade off. But I also tow a lot more weight very often. My thinking is it would be better to stay with the 4.10's and help save the expensive stuff (your tranny). Plus you never know what you may want to pull in the future...
I would really want to drive a similar truck to yours with 3.55's before jumping into it (if at all possible). Or like Talyn suggests, the 3.73's make be a good middle of the road for you. But you'll probably have to put 32,000 miles on it before your back to break even.
Lets say it costs 500 to complete the swap to 3.55's and the gain is 3 MPG when not towing, let's say 15 MPG with 4.10's and 18 with 3.55's. Let's also assume $2.75/gallon (who knows what it will do).
(4.10's) $2.75/15 = .183 cents per mile in fuel.
(3.55's) $2.75/18 = .153 cents per mile in fuel.
Net savings in fuel comes to .03 cents per mile. $500 for the swap divided by.03 comes to 16,666 miles before you break even... a year's worth of driving or less to offset the cost. To me that doesn't sound like a good trade off. But I also tow a lot more weight very often. My thinking is it would be better to stay with the 4.10's and help save the expensive stuff (your tranny). Plus you never know what you may want to pull in the future...
I would really want to drive a similar truck to yours with 3.55's before jumping into it (if at all possible). Or like Talyn suggests, the 3.73's make be a good middle of the road for you. But you'll probably have to put 32,000 miles on it before your back to break even.
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From: Thomasville, GA
I had 4.10's in mine and swapped to 3.55's when I did my SRW swap... gained some MPG's driving only highway but a mix of highway/city it only went up about 1 mpg.
I'd stick with 4.10's. It definately doesn't pull as hard with 3.55's and I'm running a 285/75-16 tire and only 2wd.
Keep the 4.10's or do 3.73's. I wouldn't do 3.55's
I'd stick with 4.10's. It definately doesn't pull as hard with 3.55's and I'm running a 285/75-16 tire and only 2wd.
Keep the 4.10's or do 3.73's. I wouldn't do 3.55's
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From: Shepherd Tx
rear end
Thanks for all the opinions, think i will go with all the opinions and stay with what i have, might put a chip in it a little later, by the way my truck is in good shape,but i mised on the mileage it has 190000 miles.
Thanks Jim
Thanks Jim
