Official Crawlbox BS thread!

Yeah, you might be a lost cause

 

Same two trails I plan to run next year, and why I started reading this thread. I probably have the least capable truck out of my local friends. One SAS'd his 4runner, and is on 40's the other did RCLT and is also on 40's. Bought my truck used without alot of knowledge beforehand but I'm trying to make it my own... Season got cut short last year after breaking my spindle.... That log was a huge help

 

No idea, 6500lb truck might be too much long term on a tacobox?

 

MC 230:1 vs NWF 125:1 and what you reckoned?

 

There's no right or wrong answer, lol. That's totally up to you. 10 people will tell you 125:1 and another 10 will tell you 230:1

I like SLOW. The slower the better, especially steep drop

 

Any consensus here on where the crossmember should support the t cases? I’m awaiting NWF dual cases (chain drive) so my mounting points for a t case are either at the transmission mount only, or FROR style at the back of the Tcase. Doesn’t appear to be anything in between those points (though could technically do both). I remember previous discussion folks saying to have as many of the mounting points as possible. What do you guys think?

 

I ran it two ways: for the first 10yrs of having a crawler only being supported by the trans mount with a 4xinnovations heavy duty poly mount. For the last 5 yrs I have it supported off the rear most case (I have a lefty behind my crawl box) with a factory style rubber mount. I moved it chasing really bad drive line vibrations after my SAS, turns out I have been phasing my driveshaft the wrong way and that was the cause, not the crawl box mount.

Both ways were wheeled hard as hell, both ways I didn't have any issues. I also have been running factory style rubber motor mounts. This is all on a 1st gen taco.

 

I’m going to be running mine off the tcase mount (NWF ecocrawler to gear drive case) and plan to tie to the frame in 4 spots. 2 behind the rear case mount and two in front of it. I’ll probably run something up to the trans mount just for peace of mind; but I highly doubt it’s doing much of anything.

 

Since I’m going chain drive to chain drive I’m thinking I’ll mount to the back of the back case with a FROR crossmember clocked as much as I can get it and then maybe use a transmission mount if I can make it work (I’m doing a prerunner conversion to 4x4 at the same time)

 

So you still like dual rear drive shaft? Did you do an aftermarket carrier bearing?

 

Yes to the 2 piece, and I still run an OEM carrier bearing.

 

Just got a new TG 4.7 crawl box for my 3rd gen Tacoma. Anyone have any issues with the splined coupler that goes from the trans to the crawlbox? Brand new mine has some play in the splines. Compared to the factory coupler I removed from the t case it’s about 10 thou larger od. The splined portion on the t case that goes into the back of the crawlbox seems to be a nice fit. I feel like the fitment should be tighter (like factory) to avoid issues on and off throttle when driving, and going from drive to reverse when wheeling. And reading through the thread I should be putting anti seize on all the splines to avoid issues?

 

That's absolutely normal with TG product

 

Thanks for your input, not exactly what I was looking for in terms of help regarding this. I have TG fab housing front and rear on another rig and they’re very high quality, so that doesn’t make any sense to me.

 

Can't speak to the 3rg gen, but I run MC gears with TG adapters. I had to use the MC coupler because the TG one wouldn't fit over the MC splines. The fitment onto the trans side was also different between couplers which doesn't makes sense. I think the TG quality control just isn't there.

 

The fitment is not terrible, just don’t know what it should be or what to expect, it’s not the same tolerance as the coupler I pulled off. So just don’t know if I should be concerned. Of the people that have installed these. Are you guys sealing up these areas on the front/trans side of the crawl box? Or just sealing the mating surface and letting the gear oil fill the area between the trans and crawl box?

 

This will make you sleep well at night: https://irate4x4.com/threads/trail-gear-trans-to-t-case-coupler-failure.395717/

As for sealing it up, just seal around the edges where it mates to the trans. The oil that spits out the top by the shifters will drain back into the crawl box through one of the lower holes. If you have a 5spd you will need to cover the backside of the tapped bolt holes for the trans mount bolts on the trans up with JB weld or it can leak out of there. Scuffing up that smooth surface will help the RTV stick to it. I always use permatex "the right stuff" on my crawl boxes.

 

Funny enough, it’s probably the MC side that you had an issue with. I know on the mini truck stuff, MC’s 23 spline is only compatible with MC’s 23 spline because it’s considerably larger than factory or TG 23 spline. I just had this issue with my NWF ecocrawler to RF1A where the sumo gears 23spline is a copy of Marlin and had to be machined down to fit into the factory 23 spline output.

 

When I compared them, they were roughly the same size. the spline profile is what was different for me. the MC splines also had a larger major diameter preventing the TG coupler from fitting.

 

Dreams would be a NWF, 74weld portals 5.29s and 37s would be the ultimate crawer daily.