Diff help

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basher
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Diff help

Post by basher » Fri Oct 09, 2015 2:12 pm

Blew the back diff on my brothers sj, anyway it was a 5.125 ratio which I couldn't find but assumed for some reason I could fit a vitara diff, probably due to seeing matching ratios, anyway the vitara diff I got is a lot bigger and won't fit, where have I messed up? What cwp of that ratio fit a sj diff?

Anton
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Re: Diff help

Post by Anton » Fri Oct 09, 2015 2:19 pm

The rear diff on a vitara is larger than the front one. You need the front diff if you want to fit it in the back of your brother's SJ, as SJ front and rear diffs are the same size as vitara front diffs.

Having said that, I think there's more to a swap than just bolting it in - ideally you want to pull the guts out of the vitara diff and install the ring gear and pinion into an SJ diff as they are stronger. I'd imagine Dan is your man for info, as he's done it a bunch of times.
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dan_2k_uk
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Re: Diff help

Post by dan_2k_uk » Fri Oct 09, 2015 4:55 pm

You will need to build Vitara front ring and pinion gears into an SJ carrier with SJ 26 spline side gears.

Also worth considering is a spacer to re-center the case in the carrier as the Vitara pinion is smaller. Also a can to hold the pins in as the Vitara ring is too thin to retain them.
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basher
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Re: Diff help

Post by basher » Fri Oct 09, 2015 7:13 pm

Cool il have a look at the old diff and see what was done

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Re: Diff help

Post by basher » Sat Oct 10, 2015 11:31 am

This is the old set up, where should this spacer be, does it offset just the crown wheel or the actual case? Wear on the crown wheels looks alright so must have been meshing ok up until I munched it
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dan_2k_uk
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Re: Diff help

Post by dan_2k_uk » Sat Oct 10, 2015 7:24 pm

It would go between the crown/ring gear and the case to re-center it. It can be fitted without but the side bearing adjusting ring on toothed side of the ring/crown the will be close to the limit of thread/adjustment.

You can see the pins are coming out too as the Vitara gear doesn't have an extra lip to retain them. You can remedy this with a can that slips over to hold them in or a couple of tacks of weld on each one.
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Janspeed manifold, LWB Vit vented discs and calipers

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basher
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Re: Diff help

Post by basher » Sun Oct 11, 2015 11:40 am

Great thanks, does anyone make the spacer, sleeve?

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Re: Diff help

Post by dan_2k_uk » Sun Oct 11, 2015 2:18 pm

Not that I know of. If you buy a complete front Vitara diff to take the gears from and know someone with a lathe the redundant Vitara case can easily be made into one.
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Janspeed manifold, LWB Vit vented discs and calipers

Build thread -- Build photos -- HLA-Artwork
Coming soon: YJs, Trussed axles, Full float rear.

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