[wombat178]

srupid question i know but has it or could it be done. I think it would only work on the autos as one of joes output bearing supports could be used. A custom cradle to hold it tailshafts etc. Would get high range reduction with the right gears and even lower low range. Could it be done was just a thought

[christover1]

Has been done many times.
Can't add any more, because I have not done it.
Look around our forum, you will find a lot

[shandy92]

have a search mate, there was a big thread on this a few months ago

[Gwagensteve]

The rear bearing support made by Joeblow and Trail Tough is only required if you have an auto. The manual gearboxes don't require this adapter - remove the transfer and slide the jackshaft in.

As for gearing, youll nned to crunch some numbers to work out if it's going to work for you. It will lower high range by minimum of 40%, and as much as 70% depending on the gears used - that's my sierras have 3.7 diff gears and vitaras 5.12.

If you're planning really big tyres, it's probably the best option though considering the undertaker isn't in production anymore.

Steve.

[wombat178]

It was just a crazy thought I had but didn't realize what the Sierra gearing was like I can see it would work in something that had huge tyres but I didn't buy a vit for that guess I just get stuck with my high range gearing. Will see what low range is like after gear install

[Gwagensteve]

Low range will be sweet after transfer gears - really nice. It's high range that's the problem, as you're aware.

Steve.

[wombat178]

I guess I'm just lucky it's auto that kinda helps its ok with 30's but would like to go 31's in the future for a tiny but more pumpkin clearance at the rear

[Fatzook]

wombat178 wrote:

I guess I'm just lucky it's auto that kinda helps its ok with 30's but would like to go 31's in the future for a tiny but more pumpkin clearance at the rear

Shave the housing. It will give you the same amount of clearance as going to a 31" tyre. Great time to fit a locker also.

[christover1]

My Vits an auto LWB with 31's and t-case gears.
It is very acceptable on road, though not brilliant.
I do think that 30's would be better on road, but may be too small for low range.
I love my 31's.

[wombat178]

Have the locker already what is this shaving the housing you speak of? ???

[wombat178]

Ah just fiund some pics that you put in a post fatzook i now understand perfectly could be on the cards i think

[Gwagensteve]

Some inspiration - there's lots of meat that can come out of a Vitara housing.

Steve.

[Fatzook]

Gwagensteve wrote:

there's lots of meat that can come out of a Vitara housing.

Steve.

Yep!

[wombat178]

Oh wow didnt think you could go that far how well does it seal with the lower mating surface cut off? Heaps of sealant.and thanks for the pics im having evil thoughts involving a grinder and the mig

[wombat178]

Oh just looked again its not cut off its been a long day

[Gwagensteve]

Actually, I didn't realise how confusing those photos were. The shave was done as part of converting a vitara diff into a full floater for a sierra, so I had the cover cut off. tHere wouldn't be any need to to this as part of a "normal" shave.

Steve.

[tanshi]

I have looked at the vitara diff and wondered if you could shave the bottom even more.

Actually cutting the bottom off through the bowwom two mounting holes and relocating them outward 20mm and upward.

you would still end up with about 5mm of sealing surface but would gain about 15mm more under the lowest point.

thoughts ??

[Gwagensteve]

I agree I think that's possible, but I'd worry about the whole thing flexing and being problematic. Stock spacing between the case bolts is 85mm. to do what you're saying, spacing would go out to around 120mm, couple that with say 5mm of seal face and I reckon that's going to get leaky.

On the third member side, the stud area is thicker, so you'd loose that, and looking at it quickly, I'd say you'd also have to grind into the webs to get to the studs where they would want to end up, reducing strength even more.

Might be a good option for a comp car, but for something that sees road km's, I'm not so sure. Interesting though - give it a go I reckon - it would be hard to find a cheaper housing or third to experiment on.

Steve.


PS Had another think and there's an additional problem - the stock holes in the housing and the third would have to be welded up and probably machined, or you'd end up with only 2.5mm of seal surface around the old stud locations. More labour.

[tanshi]

i have a spare housing so i'll have a play i think.

yeah its going to be a fair bit of work. and for 15mm its hardly worth it.

but i'd like to know if it will work or not so ill give it a crack.

[Gwagensteve]

15mm is as good as a 30mm bigger tyre, so a win is a win, but it is in that "diminishing returns" category - everything you do beyond 31's is an exercise in more $$ and labour for smaller and smaller gains.

Steve.

[wombat178]

Im going to find another housing and get happy with the grinder see how far i can take it. Now to phone the wreckers