I've just been doing more research into t-case set ups for my large build that will take place next spring/summer. This years goal is to get my truck on the road and wheel it a little bit. Next years goal is to rework the drive line, beef up the axles to take the new power plant and some 37 or 38" meats.

Driveline will be a TBI SBC 350 coupled to an NV4500 coupled to Toyota cases sending power to Toyota 8" axles. Axles will have a high pinion e-locker up front, v6 e-locker out back, Longfield 30 spline and hub gears and either Alloy USA or Yukon rear shafts (I figure that should hold up to a mild v8 with just intake, headers and a mild camshaft).

Now my plans for my Toyota cases are interesting and I got the idea from BigMike over on Marlin Crawler Forums. So I'll start by laying out the parts list:

3 Toyota Gear Driven T-Cases
Marlin Crawler MC08 Adapter
Marlin Crawler MC08-R10 Adapter (10* clocked)
2 Marlin Crawler Total Spline 2.28 Inputs (23 spline)
Marlin Crawler 4.7 Gears (rear case)
Marlin Crawler Twin Stick (rear case)
Front Range 10* Clocked Crossmember
Front Range Rear Driveline Disconnect

The triple cases will be cool because it will give me several different gearing options depending on what I'm running. A single 2.28:1 stock ratio, a 4.70:1 ratio, stock dual ratio 5.20:1, ulitmate dual 10.716:1 ratio and SUPER low triple 24.43:1 ratio.
This coupled to the NV4500 with it's first gear of 5.61:1 and 5.29 gears will give me some awesome crawl ratios.
Stock (2.28x5.29x5.61) - 67.66:1
Stock Dual (2.28x2.28x5.29x5.61) - 154.27:1
Ultimate dual (2.28x4.7x5.29x5.61) - 318.02:1
SUPER low triple (2.28x2.28x4.7x5.29x5.61) - 725.08:1

That is some LOW gearing imo and will basically let me run just about any single trail I can ever dream of running.

My questions are:
What does everyone think of this set up? Both the triple cases themselves and the driveline set up as a whole?
Will the axles (with the planned mods) even hold up to all of that torque multiplcation that will be going on when in low low low?
Opinions, as always, are welcome.

 

Not to piss in your cheerios but toy cases will not hold up, at least the rear one. I highly suggest you look into the a Dana300 transfer case mated behind the first crawl box(toy). It has tons of upgrades and is tons stronger than a toy case. It also has the ability to do front digs and was the basis for the Atlas and Stak cases.

 

I wonder how useful that 725:1 ratio will actually be... with 38" tires that works out to 2 inches per second...

 

I'd like to keep a Toyota drive line but I'm not dead set on the v8 thing. I just want something a bit newer then my 22R and fuel injected too.

Not 100% sure what you mean.

 

I've played with the idea of a 22RET swap. Would offer more power then my 22R and also allow room for upgrades.

 

He means that you'd be going sooo slow that for the once or twice a year that you use it, is it worth it? Especially if you're going to be running a V8 or anything bigger than the 22re...it should have plenty of power to get over anything without the third T-case. If it comes down to it, use more skinny pedal.

You'd have alot of bragging rights, but it just seems like the 3rd case is alot more hassle than it's worth for how little it might be used. Just my two cents.

 

700:1 crawl ratio is not practical, I would spend the money elsewhere.

If you are set on running 38s with v8 power in a crawler I would consider bigger axles. In my opinion, if you were planning on spending that kind of money on your tcases, I would allocate most of that into getting D60s (or similiar) and then go from there. Dana 300 is not a bad idea as mentioned before. Toyota 23 spline stuff may be OK in a light Toyota pickup though.

 

If you are doing an engine swap, I would go for something newer with more power if I had to do it again (2.7 or 3.4), although my 22RE I have now is a huge improvement over the 22R.

 

u trying to pull a train car? I think the duals with 4.7's would be plenty but everybody has their own wants and needs. And i believe there are quite a few runing toy cases on pirate with setups like u have.

 

If you have unlimited funding, sure, why not? But if you have unlimited funding, you'd be a fool not to put in custom D60's or portals, or whatever.

A few thoughts:
- With as much power, and possibly gearing, as you're going to have, don't go lower than 4.88. Both 5.29 and 5.71 only have 7 teeth on the pinion, you gain a lot of strength by sticking to 4.88 (8 teeth) or better yet 4.56 or higher (10 teeth).

- The third tcase adds to your powertrain windup and therefore reduces the "feel" of the powertrain.

- Agreed with above, 700+ crawl ratio is for bragging rights only. ALL 'wheeling takes SOME momentum. Really, 200+ is too low for most situations. (A little bump is often better than sitting there humping the rock and digging out)

- If you're going with a V8 swap, why not put a 3 or 4 speed Atlas in there and get rid of all the adapters and extra length? Atlas would allow you to select either driveline or both for RWD low to turn or FWD low for digs.

 

My 22re is in the shop with a piston down, got something from Advanced Adapter thinking about doing the "trail Tammer" gear swope. Doesn't that just give you a lower low range so you can run most trails in say 2nd or 3rd instead of 1rst with no where to go but up ?

 

For a power plant go with the 2RZ or 3RZ (whichever is in the Tacomas) or the 5VZ 3.4L.

 

I think I will stick with a 4 popper. Right now the cheapest and easist swap would be the 22RE.

Thanks for the opinons everyone, I'll just do regular duals with some goodies. Just thought I would get some opinions from everyone else.

 

Think about your brakes too. When you have that much torque going to the wheels, imagine trying to stop it. There was an article on a FJ40 with a tripler and a v8 and he said that it is hell trying to stop it when it's moving. Just food for thought.

Brandon

 

That's a good point too Brandon.

 

Full float kit gives you rear discs.... and with the way you're building this to be used, the FF would definitely be a good idea!

 

I'm going rear disc before the truck is even on the road this year.
Full float, we'll see.

 

good choice there.

Tripple cases is simply for bragging rights: see, my truck can go slower than yours, kind of thing. Pretty useless on the trail.

Most of the guys i know who drive duals either drive stock lowrange, or 4.7 low to crawl....almost never with both in, unless requiring super slow speeds, but even duals in double low is frustratingly slow.

 

After driving with my 4Runner with a dual ultimate crawler, I couldn't imagine needing anything lower than the 223 to 1 I've got. Have you ever been in a truck with a dual ultimate? Find a buddy with one and put it in double low, it's crazy slow.

Also, V-8 and that low of a crawl ratio probably wouldn't last long with the Toyota drivetrain.

 

Ditto everyone else on triple cases being overkill. And definitely requiring major rear driveshaft thought if you want it to be vibration free on the road.

If you went with a NV4500 tranny, most versions of those have a granny 1st gear. Engine torque * 5 * 2.28 * 2.28 = murder for rear t-case.

I run a 3.0 Toyota, R150 (higher first gear than a W56), 4.7:1 t-case, 4.10 pumpkins with 36" Swampers. I think swapping 5.29's in my diffs would make my setup perfect. Or add a 2.28 crawl box to give a "mid" range for trail riding. Right now 5th Low is nearly the same as 1st high, and I'd like 3 Low through 2nd high for trail riding, and the 2.28 low range would give me that. Then I could use 2.28 * 4.7 and use 2nd on my tranny to crawl and keep 4.10's in the pumpkins.