crawl ratio (1 Viewer)

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I'm trying to decide what crawl ratio will work best for the drive train I plan on running.
I've got a 350V8/H42/toybox/splitcase. I'm thinking about using 5.29 gears in the diffs on this build. What I'm trying to decide is if its worth the extra $(~$450) to buy the 4.7gears for the toy box or just run the stock gears The difference is between ~98:1 or ~200:1
I would think that 98:1 should be plenty low but I don't know how useful the lower gears and different options would be.

Is th 200:1 to low to be useful or is it just a matter of preference?

What would you run?
 
200:1 is nice, very rarely.

Most of the time, 100:1 is perfect.
 
You plan it's run a buggy ? 200:1 it's pretty much . ..

Uh... what? Not makin' fun, I just have no idea what this means.

-Spike
 
I did not see tire size here, nor did I see if this vehicle will be street driven.

The reason I ask is that 5.29's will put a Cruiser right back at stock in the gear ration with 37-38" tires.

Also, those tires are also very good sizes for 80-100:1. I was 100:1 with 42's and it was a tad too high.

I have no HP on my motor and I use my 200:1 all the time.

I knock it out to 80:1 to slam it up hills.

It is good to have options.

4.11's will be stronger overall, but will put more stress on your driveline.
 
This is going in a leaf sprung FJ40 build with 37-38" tires and chromo toy axles. It will not be street driven much but I would like to be able to drive it to local trails and even moab.

It looks like my options with these setups are based on H42 3.5551st, split case 2.27low, toybox 2.28/4.7
18.8:1, 42.7:1, 97.3:1(2.28)
or
18.8:1, 42.7:1, 88.4:1, 200.7:1(4.70)

Would the 200:1 create so much torque that I would risk breaking stuff real easy
 
I have a 2F, H42, Rock Box, Orion 3:1, 4:11's.

From Gino at AA's calculations I'm at 198:1.

It comes in handy but it is rare that I need to use the super compound low. I do it more to piss off my fellow club member out on the trail. In good humor of course.
 
Uh... what? Not makin' fun, I just have no idea what this means.

-Spike

Don't get mw wrong ..

Actually I'm not a rock crawler expert .. but I thought 200:1 it's pretty much, most for a " cruiser " that not do the same things ( or are suppose to do ) as a rock buggy. Rock buggy with 40" + tires 200:1 come perfect or at least it's nice to have plenty of options when you gotta do some serius rocks ..

just my .000002 cents.
 
If you get the 4.7 toybox I think you will find yourself doing most your wheeling with the crawler box engaged and the split case in high. This isn’t exactly ideal as you will be putting huge torque on the input of the split case. I haven’t heard of the inputs failing on the split cases but my boys have been breaking 23 spline input/output whatever shaft between the cases. I would suggest at least starting with the 2.28 crawler box and if you find you need more gear (I don’t think you will) you can drop lower gears in it.

And Tapage, 200:1 is really only usful if you are running a 4-banger. I have a rockcrawler that is on 40s with only 67.5:1 granny but my motor also runs at 200rpm. 80:1-100:1 with out losing baja gears would be so money.
 
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I just talking about me .. I have 4.56 and 3.05 in low .. with my diesel engine I'm been able tu run it at 1000 rpm easy .. and it's nice .. I thought if I get 100:1 would be plenty of .. ! ( dreams .. dreams ! )

Anycase I have no rocks options ( quality ones ) as you have over there ..
 
I run a 2f/sm465/toybox(4.7)/split case and i'm at around 289:1. Haven't tried it out yet but I will be soon. Tho I will be soon. From the putting around I have done around here low low low is stupid crazy. 4 grand and i'm barely moving.
 
Note: it looks like marlin is making a 3.0 crawler box, maybe a happy medium.


any details on this?
i didn't see it on their site when i just looked, but i don't get on their forums, so maybe it's in there somewhere
 
anything is better than the stock 25(ish):1! I'll be going to SM420 + 3spd case and I'm pretty sure that since it doubles and then a little I should be able to do fine. I'm usually only doing places like rattlesnake so anything higher than 50 is way too high and anything lower is usually wasted gearing. sometimes 200:1 is nice (seen it in person before)

so basically anywhere from 65:1 to 200:1 is usually the good range ;)
 
I'm looking at a NP203 into a orion.

That'll give me a four speed case with a 8:1 lowest. It'll also be only 2:1 into the orion with the bulk of the gear reduction done in the final case.

crawl ratio seems to be a little trickier with an auto with torque multiplication at lower RPM.
 
I haven't wheeled out west but from what I've seen you may want that 200:1 option, not matter how much torque your engine makes, to keep you from riding the clutch on reaallly slow stuff.

With an auto, I don't even try to compare the numbers to a manual.. just compare auto's to auto's, and leave out the TC. With the auto, I was 59:1 with 38's, and it was basically too deep. Now I'm 40:1 on 42's, and it won't really be enough, ~50:1 would be good, but 60:1 is my next option (LoMax in the 205).
 
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