Transfer Case

Hi

I am looking to reduce the transfer box ratio on my Jimny, but don't now exactly what the best options are ... the more I read the more confused I get....
How much is involved in fitting a samurai case??? Would any of the samurai cases do or are there specific models I should look for? Anyone with experience on this that can share me some thoughts on it???

Regrads
MigCooper

The name i see mentioned most frequently for this is "rockwatt" over on difflock.
There are other options from people like Off road armoury but i'm sure someone will advise further in a while.

Hi,

There are two main ways forward:

1. Re-gear your existing transfer box with special Low Ratio Jimny gearsets

2. Fit an SJ series transfer box (various options and suppliers)

Any special Low Ratio Jimny gearset replaces one of the internal gears in you existing transfer box and therefore lowers both High Ratio and Low Ratio gearing. My car came with one of these gearsets fitted and I was not personally happy with the ratios it supplied. It was not low enough for me. The Jimny Transfer box is chain driven and both the previous owner and myself had problems with chain wear and slipping. He had problems (not necessarily related to the gearset) whilst using special Low Ratio Jimny Gears and I also had issues with the same gearset in a different transfer box. You may experience chain "whine" and rattle after fitting because the chain has a wear pattern based on the original gears fitted. You could fit a new chain but at £380 a go this is not a real option.

The SJ series route can get very expensive, but it delivers a much better choice of ratios. The solution can be broken down into two areas. You will need a mounting kit to actually fit the transfer box and then the transfer box itself. A number of companies product mounting kits (Off-road Armory, RS ENgineering and a guy called "Rockwatt"). I have an Off-road Armory one and a large number of people on this forum have fitted "Rockwatt" solutions.

The transfer box itself is again another area for choice. A basic SJ410 box will provide a small ratio change without modification, but this is not really worth doing because of the expense of the mounting kit for such a small change. The next level is a "Rocklobster" conversion. This takes the gearing down to 4:1 by mixing and matching gears from a 413 and a 410 box. A number of compaines provide this conversion, the most popluar being Rockwatt. You often have to source your own scrap 410 and 413 transfer boxes as part of the build.

Specialist companies can provide 5:1, 6:1 and 8:1 Transfer box conversions as well.

The 4:1 Rocklobster conversion is typically very noisy as it combines second hand gears that have different wear patterns on them.


I hope this helps

Martin

:ohmy:

I am getting more confused... I though that all we needed was a Samurai transfer case and a mounting conversion kit. It seems there is a lot more than that ....

So if I get a t-case from a 1.3 samurai is that any god ??? or is it useless??

thanks

The cheapest way to what is known as a Rocklobster transfer box (a 4:1 SJ transfer box) is via Rockwatt - Richard Wattam in Scunthorpe.

Basically as Martin says, he uses gears from an SJ 410 transfer box and an SJ 413 transfer box to create the Rocklobster. To do so though he needs both of these to pull the bits from.

He sells a fitting kit too. You need the right size flanges or drill others and an SJ 413 rear prop as per Martin's guide.

So you need to collect these parts, take them to Scunthorpe to Richards house, he takes 6-8 weeks to perform his magic before you go and pick it up. At a cost of about £500 or less! Compare that to the others!

His are noisy for the reasons Martin has said but I can live with that for the money. He does fit all new bearings and seals and his fitting kit includes the speedo drive. He's a top guy too who will answer any q's.

Or you can just buy it all from ORA or Rob Storr but it's not as cheap.

They are all top quality suppliers though so It's a choice thing.

You can reach Richard by sending him a Pm on difflock, his user I'd is rockwatt.

Kirkynut

Hi guys

sorry coming back to this again... If I get a SJ413 transfer case and change it by the jimny one will I gain anything? Or will this be pointless?

I am trying not to spend a lot of money at once and split the cost over time ...

The main reason I would like to change the ratio is because with my 215/75 15 my low range already sucks and I whant to fit bigger tyres so by then my low range will be come a hi range ..... :blush:

Thanks for the help.