Official Crawlbox BS thread!

If you have built crawlbox with all the chromo stuff why mess around with waiting on NWF and lose money selling your built case now? Just throw it in and enjoy the extra gearing.

If I were starting fresh with an auto, I'd go NWF in front of my stock case.

With a manual on a budget, I'd just throw together a TG 4.7 crawler in front of the stock case. I'd hate to give up 12:1 low and I've had multiple friends wish they had more low than dual stock gears at 5:1.

If budget isn't an issue, just get an Atlas and be done or a 300 behind a black box.

 

I think your right, stop over thinking it and put my case in.

 

Both seem to have good and bad, I think we'll start hearing more as it grows to more and more vehicles having the NWF Eco installed.
However, as far as Gear Ration/Selection options the Marlin/Inchworm/TG Crawlbox 4.70 is the better performer.

Tacomas/4Runners come with the factory chain drive 2.57:1 Lowrange gear ratio.

Crawlbox has the ability to have 2.28 gears in front of the 2.57 chain tcase allowing a maximum crawl ratio = 5.86:1
Your 3 gearing engagement options are:
1. Factory tcase 2.57 low,
2. Crawlbox ONLY 2.28 low, (you wont notice 2.28 vs 2.57 so almost worthless) (factory chain tcase is high range for this example 1:1)
3. Combined crawlbox+tcase allowing 5.86:1


Crawlbox has the ability to have 4.70 gears in front of the 2.57 chain tcase allowing a maximum crawl ratio = 12.08:1
Your 3 gearing engagement options are:
1. Factory tcase 2.57 low
2. Crawlbox ONLY 4.70 low, (now almost double your factory chain tcase low) (factory chain tcase is high range for this example 1:1)
3. Welcome to crawling, crawlbox+tcase allowing 12.08:1 (This gives you time and control over obstacles, increased engine braking, etc.)



NWF Eco has the ability to stack 2.57 gears in the front of your factory 2.57 chain tcase allowing a maximum crawl ratio = 6.60:1
Your 3 gearing engagement options are:
1. Factory tcase 2.57 low
2. Eco box ONLY 2.57 low, (no difference as this gear ratio is exactly the same) (factory chain tcase is high range for this example 1:1)
3. Combined Eco box+tcase allowing 6.60:1

So technically the Eco is better than a Crawlbox with 2.28 (assuming both are Same drivetrains -v6, 4.88 diffs,....) by a small margin.
But when compared to a Crawlbox with 4.70, the difference is huge, as the 4.70 Crawlbox is still twice the gear reduction. 12.08:1 vs 6.60:1




This chart, found on www.GrimmJeeper.com is a great calculator to see what these mean in real life, RPMs, wheel speed, etc.
Example is comparing V6/3.4/Auto/TACOMA/37s/4.88gears with ECO vs Crawlbox 4.7s

 

All, this is the correct way to plug this? Seems weird to use something without a head on a through hole. I used locktite but it’s bugging me.

 

Looks right, otherwise a bolt would be "captured" until you pulled off the adapter. Not that this needs it, but a stud and nut provide better clamping force than a bolt head.

 

To clarify, I’m talking about this one. Are you?

 

I smothered that in rtv when I installed that one, in hopes of it staying in but coming out easy. In hindsight I should of found a fitting and just made it a breather. I still might its still in the tote from me building it months ago.

 

Thought you were talking about the stud and nut below. My bad.

For that allen plug, make sure you have rtv around it. I would remove it and redo with rtv on the threads. Also that shifter base, if it doesnt have a gasket be sure to rtv that as well.

 

Seems weird you not use something different here.
Do they make a gasket for the shifter base? I’d rather have that then rtv

 

Honestly, this is what you really want. MC shifter base already has this design in it, but this helps better deflect the oil when splashed up by the gears rotating. Which is what causes the leaks in the first place (besides breathers being clogged.)


https://www.yotamasters.com/shop/tr...-bearings/transfercase-shifter-oil-deflector/


Can't seem to find just the gasket part number. But there are a few in this kit which is plenty. Or you can order material and cutout your own.

https://www.yotamasters.com/shop/tr...ngs/rf1a-gear-drive-transfer-case-gasket-set/

 

So then because I’m running the MC base I don’t need it? Sorry little confused

 

Dont technically need it. I ended up running one with the MC base as well. Just saying its an option, if you do both sides need gaskets/rtv.

 

I use the deflector, with a gasket on both sides of the deflector, no leaks for years and easier to disassemble than RTV.

 

Can you link me to a gasket

 

Sure, that's way toyota had it from the factory, you'll need two of P/N 36345-35010 and one of P/N 36128-35010

 

So... that's how they used the small rubber boot 36318.
Thanks for all the info.
I may also get those deflectors.
Currently debating getting shorty throw shifters, mainly for fitment.
Also thinking of adding the breather.
Still learning.

 

The gear drive transfer case does not use a breather. It is designed to naturally vent through the shift base, assuming the boot, deflector, and gaskets are in good shape you should not get any leaks out of the base mounting area.

 

I have my 2nd gen transfer case still.
Don't think my extra crawlboxes vent anywhere but to themselves.
Or do they?

 

they vent out the shifter itself as I had stated. The chain drive cases have their own vent on the housing.

 

Are you planning to run any additional supports off the crawl box(s)?