gears
Elder User
Joined: Oct 2009
Posts: 933
Likes: 0
From: Lawrenceville, Ga
I have a NP435 and 44's, truck is regeared to 3.55 gear with a 300 six cylinder and do just fine with that. Would like a little lower. The 3.55s with 38s felt perfect. Towed a pop up camper on a thee hour trip with the 38s and 3.55s and got 19 mpg. I would say 4.10s would be sufficient. Maybe a little lower if it's a 6 cylinder.
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FTE Chapter Leader
Joined: May 2006
Posts: 11,273
Likes: 99
From: North Dakota
Kirby, you make me lol.
5.38s is what I would say.
I'm runnin 4.56s with 33s on my DD but that has over drive.
Just keep the overall ratio close to what it was stock. So if it had around a 30 inch tall tire, with 3.55s, and you put 44s on it... Take 3.55/30=x/44. So that would make 5.21 for a stock overall ratio. So, jump it to the next lower gear, 5.38s to help out with the power a bit.
5.38s is what I would say.
I'm runnin 4.56s with 33s on my DD but that has over drive.
Just keep the overall ratio close to what it was stock. So if it had around a 30 inch tall tire, with 3.55s, and you put 44s on it... Take 3.55/30=x/44. So that would make 5.21 for a stock overall ratio. So, jump it to the next lower gear, 5.38s to help out with the power a bit.
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Joined: Jan 2005
Posts: 4,554
Likes: 3
From: Lubbock, Texas
Kirby, you make me lol.
5.38s is what I would say.
I'm runnin 4.56s with 33s on my DD but that has over drive.
Just keep the overall ratio close to what it was stock. So if it had around a 30 inch tall tire, with 3.55s, and you put 44s on it... Take 3.55/30=x/44. So that would make 5.21 for a stock overall ratio. So, jump it to the next lower gear, 5.38s to help out with the power a bit.
5.38s is what I would say.
I'm runnin 4.56s with 33s on my DD but that has over drive.
Just keep the overall ratio close to what it was stock. So if it had around a 30 inch tall tire, with 3.55s, and you put 44s on it... Take 3.55/30=x/44. So that would make 5.21 for a stock overall ratio. So, jump it to the next lower gear, 5.38s to help out with the power a bit.
Post Fiend
Joined: Nov 2009
Posts: 7,669
Likes: 2
I have a NP435 and 44's, truck is regeared to 3.55 gear with a 300 six cylinder and do just fine with that. Would like a little lower. The 3.55s with 38s felt perfect. Towed a pop up camper on a thee hour trip with the 38s and 3.55s and got 19 mpg. I would say 4.10s would be sufficient. Maybe a little lower if it's a 6 cylinder.
Elder User
Joined: Oct 2009
Posts: 933
Likes: 0
From: Lawrenceville, Ga
Glad I could brighten your day, well see who's right when the dude gets back on here cuz his trucks gettin' 5 mpg and running 4000 at 60 mph. You don't even have a truck with a 4 speed...
FTE Chapter Leader
Joined: May 2006
Posts: 11,273
Likes: 99
From: North Dakota
so do u think I've never drivin a 4 speed?
I swapped one into my Dads bronco with 38.5 boggers(4.56 gears), and I have owned a couple vehicles with them in them, and yes they where the "granny 4speeds" as you would call them. Aka, NP435s.
I swapped one into my Dads bronco with 38.5 boggers(4.56 gears), and I have owned a couple vehicles with them in them, and yes they where the "granny 4speeds" as you would call them. Aka, NP435s.
FTE Chapter Leader
Joined: May 2006
Posts: 11,273
Likes: 99
From: North Dakota
Ok, Take a 44 inch tall tire, with 5.38s in the axle, with a 1 to 1 top gear(ANY TRANS WITHOUT OD MANUAL OR AUTO) and a 4000 rpm on the tach.. Thats makes about 97 mph.....
So running 44s with 5.38s in top gear,(1:1) at 2500 RPM, is 60 mph....
With your setup, 44s, 3.50s, 4th gear, at about 1600 rpms is 60 mph........
In order to run 4000 rpms at 60 mph, in top gear(1:1 again),with 44s, he would need about a 8.60 gear ratio in the axles.....