[303zuke]

A mate of mine is putting a 2.5lt V6 into a LWB Sierra and has asked for some help. The Vit T/case is quite long even for a LWB, and the driveshafts have slip yokes F and R, and the low range sucks. We've decided to fit a Hilux chain driven case to the Vit gearbox. The info here flows from this swap, but might be of use to other Vit or Sierra owners.

The 2.5 V6 gearbox is an AISIN design that is also used in Diesel Hiluxes and Jeeps. Hiluxes and Jeeps both have 1:1 High range like the Vit, buit the stock low ranges are much lower than the Vit. In Hiluxes, the box is called a G52 (and ohter G series numbers in other 2wd and 4wd Toyota apps), and the AX-5 in Jeeps. It is also the box used in the SQ420D Turbo Diesel Vitara that we didn't get in Aus! Although there are slight differences with input shaft and output shaft lengths, the boxes are identical inside as far as bearings, shafts, seals, etc. By reading the Sales brochure for the SQ625 V6 Vit, I was led to believe the gear ratios were slightly different to the Lux and Jeep, but on opening the cases, all of these boxes have the same ratios of:
1st: 3.928
2nd: 2.333
3rd: 1.451
4th 1.000
5th: 0.851


The Jeep box has an identical rear extension housing to the Vit, and is used with the NP231 and NP232 transfer Cases. These have a stock Low range of 2.72:1 (49% lower than Vit) and are much shorter than Vit. Lo reduction gear sets are available such as Teraflex'x 4:1, and dual reduction cases are available such as the Klune-V. Because of the length saving of the NP231 case over the stock Vit, it might be possible to fit a dual reduction case without too much extra length. Unfortunately, the Jeep transfers use SAE splines, flanges and unis, so it might be tricky making up a driveshaft.

The Diesel Hiluxes used a gear driven case up to the LN106, and a chain drive case from the LN167. Both of these boxes have flanges F and R and are about 50mm shorter than the Vit box and t/case assembly. The gear driven case has a low range of 2.28 (25% lower than Vit) and replacement gearsets are available from Mark's adapters in 4:1, 4.7:1, and 5:1. There are also dual case adapters such as Marlin Crawler which use 2 sets of reduction gears of your choice. These add 6.5 inches to the length, but with the Lux box being 2 inches shorter than the Vit, the overall length increase is 4.5 inches. The chain driven case has a Low range of 2,566:2 (41% lower than Vit). I don't know of any replacement ratios for the chain driven cases.

Anyway, on to the pics!!

The box in front is the Hilux G52 with chain driven transfer, with the 2.5 V6 Vit behind it

[303zuke]

There are slight detail differences between the 2 transmissions. The Hilux has a shorter input shaft and different spline count to the Vit. It will be necessary to swap over the input shafts and bearing retainers to use the Lux box behind the Vit V6.

[303zuke]

The gear selectors are in identical positions and the bolt patterns for the lever mounts are the same. However, the Vitara has the actual lever much farther back and uses an extension housing to remote mount the lever. This places in a position that fouls the t/case lever on the chain driven case, but could possibly be used with the gear driven case if the LN46 lever position is used. As we will be fitting it to a Sierra which will have transmission tunnel mods anyway, we will be using the Hilux lever position.

[royce]

I have always wanted to say in on 1 on this forum and I reckon this thread could be worthy

[303zuke]

The output shafts at the rear of the box are also different lengths. The Vitara is the shortest. When used with the Jeep AX-5 and NP232, it makes for a very compact overall length. Although the Hilux has a longer shaft from the box, the overall length of the Box + Case is 50mm shorter than the Vit!

[303zuke]

As mentioned, the bolt pattern on the Vit rear extension housing is the same as the Jeep AX-5. Without the hassle of stripping the gearbox to swap input and output shafts over to fit a Hilux case, a Teraflex LOW 231 HD Transfer Case-23 Spline Short Input kit would make an ideal choice in a SWB sierra with Dana axles!

[303zuke]

And what about engine choices?? Although not necessary ideal weight wise or even engineer legal, there is a massive amount of engine options available for this gearbox.

The bellhousing and input shaft will fit a 2.5 V6 and the 2.7 V6. Although not used with this gearbox, I understand the 2.0 V6 has the same bolt pattern and will fit this bellhousing.

The bellhousing to gearbox pattern is one of the more common adapter types available. For stock factory engines, you could choose from the Suzuki 2.0 V6, 2.5 V6, 2.7 V6, Toyota 2.2lt L, 2.4lt 2L, 2.8lt 3L, or 3.0lt 5L Diesels. Any of the bellhousings used with the W series boxes and Petrol Y family of engines will also fit. Mazda RF 2.0lt Diesel, Peugeot 2.0lt Diesel. Jeep 4.0lt straight 6 or 2.3 4 cyl.

Aftermarket adapters are also made to this pattern for Holden V6 and V8 and Red 6 cyl, and even the vintage Ford Sidevalve V8!!

Unfortunately, the Dyna R452 box with the 5.15 1st gear is not the same pattern as the Vit bellhousing, but I'd like to crawl around the insidesof one to see if they could be used in this gearbox case. This is the box used with the Mark's Adapters HD low Lux kit

[eldo]

a very interesting read and this one should go to the tech section and get locked or even articles section royce!!!

[gravity_powered]

Phwoar!

Tech article porn!!!

[303zuke]

303zuke wrote:

The gear driven case has a low range of 2.28 (25% lower than Vit) and replacement gearsets are available from Mark's adapters in 4:1, 4.7:1, and 5:1. There are also dual case adapters such as Marlin Crawler which use 2 sets of reduction gears of your choice. These add 6.5 inches to the length, but with the Lux box being 2 inches shorter than the Vit, the overall length increase is 4.5 inches. The chain driven case has a Low range of 2,566:2 (41% lower than Vit). I don't know of any replacement ratios for the chain driven cases.

Update, update, Update!

With the strong Aussie dollar, it was a good time to source a set of reduction gears for the Hilux T/case, which required changing over to a gear driven box instead of the chain driven originally chosen. Marlin Crawler are doing a sale on their Series II 4.7 gears for a rediculously low price, and their series II are a much better gear set than those offered by Mark's Adapters or Snake Racing. Like when installing 6.5s into a Sierra, you have to grind out a little of the case for clearance on the larger gears. The Series II does away with this by chamfering the gear to clear the case, making for a much stronger assembly.

With 5.125 gears in the Sierra (due to the 1:1 Hi range), low 1st is now 95:1! Hi 1st is part way between Lo 4th and Lo 5th, giving an almost continous spread of gears to choose from.

[tanshi]

oh sweet, can any one tell me which models of the hilux had the gear selector like this? Im putting in a vitara box to the sierra and if i can get a selector from a lux to go on it it will save tunnel mods

[atari4x4]

not sure if this belongs here or not, but there is a thread on zuwharrie about using the non electronically controlled AW372L 4 speed auto trans out of the Mitsubishi Pajero 4x4.

http://bbs.zuwharrie.com/content?topic=113393.0

might be usefull info for someone wanting a non electronically controlled 4 speed auto.

[Bentzook]

When we first built the Gravitron, I had dual Hilux transfercase set-up behind the Vitara auto. We used two gear driven Hilux cases, Marlin case adapters and a alloy plate upto the Vitara auto .....