humm mount the np205 backwards and twin stick it for a 50% overdrive? then unimog axles?

 

more seriously np 435: worthy gear ratios am I ganna be able to find a bellhousing to mate it to a diesel?
ranger underdrive: cool but, say's its good for 400ft/lbs kinda wonder if its gonna live behind the diesel with that first gear, can't shift under power like the gear venders but behind the manual it should be fine
lets see what it give me for gear ratios
1:6.68-4.88
2:3.34-2.44
3:1.74-1.27
4:1.00-.73
thats some nice gear splitting,
think I'd want to look around for a set of 3.08 axle gears with all those foward choices the crawl ratio would be in the range of 80:1 right
and I think I'd want to stick with close to stock driveshafts so the U joint break before tha axles

definitly worth doesn't leave me with an auto, but gives me everything I want in a truck drivetrain

 

The Ford 435 will mate to the IDI T19 bellhousing and has the same spline count and input shaft size.

The Ranger is rated for 420 ft lbs. But since it bolts directly behind the engine, it is only dealing with engine torque. I had forgotten that you were turbo'd. I have seen them being used behind the Cummins, so I'm sure a competent driver could make one last.
As for shifting, they shift like any other manual transmission. With some practice, they can even be shifted without the clutch.

With that combo, the highest gears (numerically lowest) I would choose are 3.55's. Anything higher would put your cruise RPM too low in OD, maybe even direct with 33's or better. And it is better to spread out the gear reduction through the entire drivetrain.

Jason

 

I'd like to be able to see 1400-1500rpm for empty cruising at 60, but its not really all that vital being a truck its not gonna be empty often.

and just imagine the poor theif who hopped in there and saw 4-5 shifters sticking outa the floor
1-4 speed trany
2-overdrive
3-np203range selector
4-np205 range selctor(if I twin stick the np205)
5-2wd/4x4

 

(quote) "taller gears in the axle (numericaly lower) reduce the chance of a ring and pinion failure."

are you sure ? i think as you go lower ( up numerically ) the pinion head gets smaller and smaller... at least thats been my experience so far. and i may have a gear swap or two under my belt....i know it takes less leverage to turn lower gears, but the gears themselves get weaker-at least the pinion does. but then again, i may be retarded and just spouting smoke outta my a**................

 

I look at driveline failure as a balancing act.

If you run heavy, 3.55 gears will mean short transmission, transfer case, U joints, driveshaft and pinion yoke life.
Haul the same loads with say 5.13 gears, now the weak point has move from the input side of the differential to the output side, so the axles and ring gear are now more likely to fail.

The trick, take into consideration where you normally operate and with what loads, then make the best informed decision you can.

Where I live and the loads I haul, 4.56 gears and an overdriven transmission would be better.

If you break enough transfer cases, U joints and drive shafts that gets just as expensive as an axle failure.

 

umm I think we just said the same thing
ar maybe you just said what I meant anyway a 3.55:1 axle should be stronger gears than a 4;56:1 axle right?

 

It is correct that the lower the gearing, the smaller (and weaker) the pinion becomes. But this seems to only be a factor with deep reduction gearsets, say 5.13 and lower).

To clarify what I mean about spreading the reduction. If I'm building for the maximum crawl ratio, I don't want too much between the engine and driveline, feeding into a stock or higher diff ratio. This will make the driveline a fuse in the system. If you have enough reduction and weight that diff parts are breaking regularly, than an upgrade is needed (ie: 44 to a 60). If axle shafts are the weak point, upgrade the shafts to alloy. If you still can't make them survive, then you're back to the entire diff assy.

Jason

 

I'd like to build with the driveline (specificaly U joints) as a drivetrain fuse its a lot easier to carry U joints then axles on a wheeling trip

 

Build it not to break, period. It's really not much to ask with only 33's.
Although I've changed plenty of parts on the trail, I'd much rather do it in the shop as preventative maintenance, rather than breakage.

Jason

 

then again if you drive like some of my buddies there is no such thing as won't break

 

with me driving it'd take bigger tires than 33's to break even the dana 50 I loved the 4:1 transfer case in my rubicon because it meant no throttle needed to get things moving and no sudden power hits on the drivetrain

 

With the gas tranny and 4.10 gears the torque of the diesel will either move or sit there and slowly spin the tires without touching the throttle.

 

thats what I'm looking for; think I can get there and keep the c6?

 

Well normally an auto doesn't hook up at an idle.