Ok, sorry for the lame question, but what exactly does having a custom tcase (aka marlin) or just different gears like 4.7's get you as far as offroad proformance goes?

thanks

 

A long ways...if you are rock crawling the slower you go the more controlled you are and (usually) the more you can do. When I wheeled with Schaefer this past weekend (252 to 1), it was very apparent what lower (read much lower) gears would do. In places where I would have to "bump it" he could either just crawl up or use a much more controlled bump.

If you have a manual trans and want to rock crawl, it's the only way to fly. However, you also need traction aiding devices in both axles to make it worth the investment. A crawler with open diffs won't get you very much farther down the trail.

 

hmm.. good to know.
I have a auto trans and open diffs.. I'm thinking of getting an auto locker for the front and an ARB for the back, but those both cost $$$ so we'll see how long it is till I get them.

 

Get your lockers and wheel it. With an Auto you can use your brakes to go slow. SteveO doesn't have a crawler, he has an auto and double lockers and I haven't seen anything he really couldn't do.

 

Crawlers allow you to go slow.

Auto's allow you to fake it by driving with one foot on the gas and the other on the brake.

Lockers will get you farther and are a really solid first trail mod.

Marlin cases are not custom, they are just a regeared stocker, or a stocker plus the reduction part of another stocker.

A Dual Ultimate Marlin behind and auto would be endless gearing selections.

Optional waterfall on Poison Spider. One rig has a crawler behind the 5 spd, the other is an auto. The crawler rig takes two guys hanging on the front bumper to load the front end for climbing. The auto rig takes two guys pulling the winch cable to load the front for climbing. Both rigs make it cleanly.

 

Some of the places I've been, having a crawler is required. One example that comes to mind is out in Johnson's Valley. A steep climb offcamber, turning to the left over very loose rock. In this case wheel spin is bad, with both lockers on and going as slow as I could, I got just enough traction to creep up. The control you get with dual cases was worth it, but before you install one add lockers front and rear.

Another note* most of the hardcore rockcrawlers run stock 4.10's with dual cases, because of strength issues. If I ever break my R&P gears I may go back to stock as well, if not 4.30's.....

Where the dual cases help me most are; backing my boat into the driveway 2WD crawl box engaged. Also when I'm doing survey work I'll have my back hatch open and let my rig crawl ahead of me while I'm setting stakes...Auto pilot

 

You cannot add a crawler box to a second gen runner auto. The transfer case is a build on/build off case, which is hydraulically controlled. The later model autos could convievabley have a crawler installed, but already being an auto there really isn't a point. Just use the reduction gained by your torque converter, or swap in a manual.

I recently installed a crawler with 4.0 gears and a turbo trans in my 87. The rig is IFS, unlocked in the front, and the control i gained was very much apparent. If not more traction, gaining 6 more gears was a huge advantage. Now I have gears for any situation.

 

You can install a crawler box or two on an automatic:

http://www.4x4wire.com/toyota/tech/autocrawler/

 

An auto does not make up for a crawler. You can almost fake it on the climbs, but not on the descents. Even with more diff gearing than I "ought" to have, I want more gear for going down hill and to crawl controlably.

 

Just be sure to have a nice large tranny cooler when you "fake it". Slipping the torque converter so much generates a lot of heat. As we all know, heat is the #1 killer of auto trannies.

 

Indeed you are correct...however you just rectified my point. I stated that a crawler could not be mounted to a second gen runner automatic (IE A340H) YOu could, however, use a later model auto trans (A340F) due to its mechanical transfer case which is not reliant on hydraulic control, like the 95 and earlier models are. So, indeed a crawler can be mounted on an auto. 96 and up that is