Larger tires and gear change
#1
Better OUT then IN
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Join Date: Feb 2011
Location: South Florida (Ft. Lauderdale area)
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Larger tires and gear change
I'm eventually going to be up sizing my tires to close to 35" (285/75-18) from the stock 32" (275/65-18). I'll be lifting as well to avoid rubbing.
I currently have a 5.0L with 3.55s.
My question is, with that upgrade, would regearing to 3.73 provide the same ratio or should I go for 4.10s?
My concern is loss of power with the larger, heavier tires.
What can I do to keep the power as close to stock as possible and possibly provide a little more per the stock?
I currently have a 5.0L with 3.55s.
My question is, with that upgrade, would regearing to 3.73 provide the same ratio or should I go for 4.10s?
My concern is loss of power with the larger, heavier tires.
What can I do to keep the power as close to stock as possible and possibly provide a little more per the stock?
Last edited by justjimmy; 05-05-2015 at 04:28 PM.
#2
Member
Best bet and bang for the buck would be a custom tune. Love mine. I'm running 3.31 gears, 5.0, 2wd, 4" lift/level and currently 32" tires, planning to jump up to near 35's and with the added power I already have, I am quite certain the heavier tires will be no issue at all, the power from the custom tune will blow your mind.
I have 5* and MPT and no complaints with either, oh and an sctx4 tuner to do the programming.
Only have 6 custom tunes right now, have another from MPT in the making.
.
I have 5* and MPT and no complaints with either, oh and an sctx4 tuner to do the programming.
Only have 6 custom tunes right now, have another from MPT in the making.
.
#3
I have a 2009 with a 5.4l and 3.55s. I am running 35s on a leveling kit with 5 star custom tunes and I'm getting 16mpg interstate and I have more power now then I did stock with stock tires. And the truck is faster. The 5.0 has way more power by itself. The 35s with a tune will be fine with those gears. And will be less then 1/4 the price.
#4
Senior Member
2014, 5.0, 35s, 3.31 gears, 5 Star 87 perf/tow tune. I'm going to be getting 4.10 gears in a few months. The tune is incredibly good, my 315s even get a little loose sometimes. I just think I'll enjoy the shorter gearing a lot more. Right now it doesn't shift to sixth until 51mph, so it's constantly shifting in and out of 5th/6th during my particular daily drive.
#5
Senior Member
Dont waste your time with 3.73s, it isn't a big enough jump to warrant the cost. If youre going to regear, go with at least 4.10s if not even 4.56.
However, like others have said already, you can probably get by with just a custom tune and save a lot of money. 1st gear is pretty short on our 6 speeds, 4:17:1 IIRC. A lot different than the 4 speeds of the past.
However, like others have said already, you can probably get by with just a custom tune and save a lot of money. 1st gear is pretty short on our 6 speeds, 4:17:1 IIRC. A lot different than the 4 speeds of the past.
#6
Ford Accessories Manager
I have the 5.4 with 35's and 3.73, noticed a substantial power loss. Don't regear to 3.73, go into the 4's, or as mentioned, try the tune.
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#8
Senior Member
I'd go 4.56 and a custom tune.
#9
#10
Senior Member
There are gear/tire change calculators on the internet that will show you how your effective gear ratio will change when you swap tires are gears.
For example, I have 3.55. I am installing 295/55/20(32.8) Toyo AT2s on Friday. My effective gear ratio will be 3.45. This is ok with me as some chevy's come with 3.42 gears and a 5 speed tranny. They dont have near the power either. If I had 3.73 gears, the tire change would move my effective gear ratio to 3.63.
I have a 5* tuner in the mail right now, supposed to arrive same day I put the tires. I will be installing this after the tire change. I am interested to see the before and after changes in power. I will be running the 87 Perf/Tow tune.
I don't disagree with the guys that say you can't tell the difference especially with a tuner, but you cant get around mechanical advantage and its affect on power to the pavement, fuel economy, & etc.
If money wasn't an object. I would have changed to 4.10 gears and ran 295/60/20(34.5") in the same tire.
For example, I have 3.55. I am installing 295/55/20(32.8) Toyo AT2s on Friday. My effective gear ratio will be 3.45. This is ok with me as some chevy's come with 3.42 gears and a 5 speed tranny. They dont have near the power either. If I had 3.73 gears, the tire change would move my effective gear ratio to 3.63.
I have a 5* tuner in the mail right now, supposed to arrive same day I put the tires. I will be installing this after the tire change. I am interested to see the before and after changes in power. I will be running the 87 Perf/Tow tune.
I don't disagree with the guys that say you can't tell the difference especially with a tuner, but you cant get around mechanical advantage and its affect on power to the pavement, fuel economy, & etc.
If money wasn't an object. I would have changed to 4.10 gears and ran 295/60/20(34.5") in the same tire.