Anyone have any insight on this matter?

I am going to be putting one of the various stray wagoneers that wandered into my shop together soon - and this one will be more of an expedition-type rig. Long haul, mild off road camping type rig: not so much a hard core wheeler.

The base unit is an 82 waggy with a 258. It will be on either the stock driver-drop front 44/rear M23 with 3.31's, or it will be on pre-1980 D44's (pass drop) with 3.54's. It will most likely run LT265-75-16's, with enough lift to clear them - but no more than necessary.

The question in my mind revolves around the drivetrain between that 258 and those axles. Durability, versus simplicity, versus total crawl ratio.

I can leave the automatic and NP208 and just go on with life - but that is the LEAST attractive option to me. I really would prefer to have a manual transmission in a vehicle of this type. The various manual transmissions that I have in stock which could be easily installed in this vehicle are as follows;

1: T-150 and D20 out of any number of different CJ's I have a few of these in stock. This would be used with the 3.54 geared pre-1980 axles. (crawl ratio = 21 to 1)

2: T-5 from an Eagle. The nice thing about it being from an Eagle means that it didn't see much off road time. In fact, this one has only about 50,000 miles on it. The upside is that it is a 4:1 (roughly) first gear and it is light, the 258 won't really be taxing the strength of the T-5, and it is a flush 23-spline output shaft, which means I can run the original NP208 with the 3.31 axles, or I can run a D300, Dodge NP208, Dodge NP241, or Dodge NP205 with the 3.54 geared axles. (crawl ratio = 34 to 1 or 37 to 1 depending on axles)

3: T-18 and D20 from another FSJ. Technically this one is a V8, so I would have to change the input shaft out, but I have a stock Ford T-18 sitting here that would gladly donate to the cause. Upside is that I will never break the tranny and I would have a 6.32 first gear. (crawl ratio = 45 to 1)

I do have other GM and Ford gearboxes/t-cases - but I see no reason to bore the bellhousing for an SM465 when I have FSJ T-18's available.

Would it be insane to expect a doubler setup to last long-term at highway speeds? What if the doubler were an NP231 out of an XJ with the NP208 behind it? It is tempting to use the T5 with a setup like that. Of course, it is also tempting to stack two of those T150's together hand at least have everything in an iron case.

Should I care about crawl ratio, or should I pay more attention to hammer-simple parts? Throw crawl ratio out the window and pull cable before I ever get close to breaking parts?

HELP! Experienced overlanders, put me on the right path.

When I orginally built up my Cherokee, I used a NV3500 (4/1 1st), a NP241C (2.72/1 LR), and 3.54 stock gears. Roughly 38/1. Idling around on a rough trail, it was just too fast. It would beat you up. But on the road, it was quite nice since the RPMs stayed down at highway speed.

I switched out the diff gears to 4.56's. Roughly 50/1. Off road, much nicer. Slowed it down enough to take the jarring out of the ride. But even slower at times would be nice. It definitely upped the noise level on road.

So what I am getting at... Gear it so it runs comfortably on the highway. Run a doubler to get your off road gearing. T5 - NP231 doubler - NP208 would be my choice.

My suggestion is an auto trans and a numerically low (shallow) crawl ratio. This way for any given stretch of road you can stay in one range and when you need to ooze gracefully over a technical section you can use the auto transmission's slip to maintain engine torque at ultra low wheel speeds, rather than having to beat up your drivetrain keeping engine torque and wheel speed optimal to each other on a manual gearbox.

I know everyone's definition of expedition is different, but my experience in North America includes a LOT of highway driving, and a LOT of graded or nearly graded roads.. and then 99% of anything I'd even consider taking a vehicle I'm driving home on, is easily do-able with <40:1 final crawl and a modestly powerful engine. I'd much prefer to just stay in 4L for the most serious sections, and not have to constantly shift in and out of low range in between those parts when they're a few hundred yards apart, etc.

I put super deep crawl ratios in the same category as crazy RTI scores and multiple shocks per wheel... if it doesn't actually improve the vehicle's functionality where it's actually being used, then it's not better. Deep crawl ratios might make sense on rock buggies, I don't see it making sense on a vehicle meant to cover distance & haul a self contained quantity of gear. Manual transmissions might make sense in the 1940s, but today's slushboxen can be as reliable as you want, they let you keep better control of the vehicle by allowing you to ooze at inches-per-hour while the engine's operating within its torque band, and they reduce driver fatigue on long travels.

I think around 50:1 is optimal for expedition type stuff. My Rubicon with an auto, 5.13's in the diffs and a 4:1 transfer case is great in the rocks, but is too low/slow for most anything else.

I don't think you'll need a lot of crawl with a tire that small, I bet 50:1 will do what you need. A close ratio trans with an underdrive will be nicer on the road and probably exceed what you need offroad so that's my vote. I've been happy with 30-37:1 with an auto and 53-ish with a manual but it's been with smallblocks and roughly 35's.

i have to disagree. first figure out what your top ratio is going to be and then decide how much you want to spend on doublers or whatever. my truck has a 13 speed with about a 12:1 granny low which puts me in the 9?:1 range without affecting my top end. i love being able to crawl over a rough section. in fact i wish it were lower still but that would mainly be for around the house moving things around.
i'm not a rock crawler by any means. in fact i'll be going 8mph max where other guys are doing 50mph. i'd rather be patient and take it easy on the truck. granted i wouldn't want to have a giant gap where it was either highway or crawling with nothing in between but the more gears you have the more options you have. between the tranny and transfer case i have 26 gears to choose from so i can crawl at 1/2mph or cruise at 1900rpm at 75mph
edit: i guess what i'm saying is it's better to have it and not need it then to need it and not have it. everyone told me i would hardly ever use the low gears but i found that i use them quite often