Gearing dilemma
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Gearing dilemma
Caught between a rock and a carrier break...
I have been trying to decide this for days now - maybe you can help sway me one way or the other.
I am converting my '79 Supercab to a NP435 with Ranger torque splitter setup. It will have 35" tires, 3/4 ton 6" lift springs and Dana 44 front, Dana 60 rear. I will sticking with the 400 engine and the truck will be used for camping, towing and an occasional off road run.
The torque splitter gives it an overdrive ratio of .73:1
I am torn between running 4.10 and 4.56 gears.
I have 4.10 ring and pinions for the front and rear already which would save a good chunk of money. I am worried though that 4.10s won't be low enough and if I buy lockers for 4.10's, because of the carrier breaks, I will have to buy new lockers to switch to 4.56's.
The charts show an r.p.m. of 2011.3 @ 70 m.p.h., in overdrive, for the 4.10's and 2237 r.p.m.'s for 4.56's.
The 400 does it's best work in the lower range but I can't seem to make a decision. Any thoughts?
I have been trying to decide this for days now - maybe you can help sway me one way or the other.
I am converting my '79 Supercab to a NP435 with Ranger torque splitter setup. It will have 35" tires, 3/4 ton 6" lift springs and Dana 44 front, Dana 60 rear. I will sticking with the 400 engine and the truck will be used for camping, towing and an occasional off road run.
The torque splitter gives it an overdrive ratio of .73:1
I am torn between running 4.10 and 4.56 gears.
I have 4.10 ring and pinions for the front and rear already which would save a good chunk of money. I am worried though that 4.10s won't be low enough and if I buy lockers for 4.10's, because of the carrier breaks, I will have to buy new lockers to switch to 4.56's.
The charts show an r.p.m. of 2011.3 @ 70 m.p.h., in overdrive, for the 4.10's and 2237 r.p.m.'s for 4.56's.
The 400 does it's best work in the lower range but I can't seem to make a decision. Any thoughts?
Elder User
Joined: Jul 2003
Posts: 997
Likes: 0
From: Weston, Nebraska
I stick with the 4.10's myself, but Texan1983 has a point you have an overdive to use, still you are looking at a lot more money and work. I think 4.10's would be fine w/ 35's, I was only gonna go 3.73's with 35's on my truck when I get it lifted, but now you that your mentioning 4.56, I'm thinking 4.10, but I have no overdrive and I need to drive it everyday, I'll probably get a built 351W before I lift it though. 35's and the 6 could be little gutless at high speeds.
Post Fiend
Joined: Jul 2003
Posts: 11,945
Likes: 3
From: Spokane, WA
May as well take advantage of that torque splitter and go 4:56. The splitter gives you 27% over in ALL gears, doesn't it? So for regular street driving you can leave it engaged and have better speed in all gears. When you go offroad shift back to a 1:1 range and you'll have plenty of power to the wheels.
Also, I don't know if this is the case for the Dana 44 but I found out that with my Dana 60 front, I use the same carrier for 4:56 as for 4:10 and down (the rear is different, but the front carrier remains the same). This might save you some $$. Call Randy's Ring and Pinion if you want to check on the 44.
Ivan
Also, I don't know if this is the case for the Dana 44 but I found out that with my Dana 60 front, I use the same carrier for 4:56 as for 4:10 and down (the rear is different, but the front carrier remains the same). This might save you some $$. Call Randy's Ring and Pinion if you want to check on the 44.
Ivan
