Front and rear LSD for SG

massni94

Forum Member
Joined
Sep 23, 2013
Messages
21
Location
Perth, Western Australia
Car Year
2007
Car Model
Forester X Columbia edition
Transmission
4 speed auto
Hey everyone,
Just wondering if anyone has done and diff mods to achieve better offroad performance when the vehicle is flexing and a wheel is off the ground. My foz is an 07 with a rear LSD, but once one of the rears is off the ground it might as well be an open diff :(

I remember someone telling me about plated wrx diffs in his foz.
Is this a good option for offroad use? I prefer to crawl over the rougher stuff, rather than approaching it with speed just so I don't need to worry about traction issues
 
NachaLuva did the mod with a WRX plated rear diff.

Venom and Rally did an upgrade with Kaaz plated rear diffs and helical type front diffs

And I did an upgrade with Quaife helical front and rear diffs. I never tested a plated diff but I think that it should be more efficient off road when a wheel is off the ground than a helical...but it needs maintenance and is probably not as smooth.
 
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I used a JDM version 2 WRX STi 2-way plated diff with AUDM 97-99 WRX axles. Its very smooth, cant notice it at all, but that is with Redline synthetic diff oil. When I change the oil I'll be using Penrite mineral oil as I think the synthetic makes it too smooth & not bind as much.

If I had the money I'd be fitting KAAZ rear & Cusco front plated diffs with either a DCCD or locking AWD centre diff :lildevil:
 
Gidday NL

NachaLuva said:
I used a JDM version 2 WRX STi 2-way plated diff with AUDM 97-99 WRX axles. Its very smooth, cant notice it at all, but that is with Redline synthetic diff oil. When I change the oil I'll be using Penrite mineral oil as I think the synthetic makes it too smooth & not bind as much.
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That's how a well adjusted/configured/designed LSD should be, mate - unobtrusive in normal use.

If I were you, I would not change the oil from what you are already using until after you have seen how the car and diff perform when off-road, or in greasy/wet conditions on-road. Just a thought.
 
jf1sf5 said:
Venom and Rally did an upgrade with Kaaz plated rear diffs and helical type front diffs
Click to expand...

Venom in the latest gearbox is running a plated front LSD as well as one in the rear. The Kaaz diff is only in the rear - the front diff version doesn't fit in a dual range gearbox. Venom's running a Cusco up front now.

I've got a Helical OBX diff up front, and it did the job yesterday when I was out having a de-stress session. It didn't do much, if anything for me when I lifted a wheel as predicted. A clutch pack unit might do you better in that situation.

Cheers

Bennie
 
Maybe it can be made to fit the D/R gearbox. After all, my front diff is out of a 6 speed STI gearbox. Doesn't seem to matter though if there is a Cusco one available.
 
Yeah true. I had to have the OBX modified, but I already knew this before I made the purchase - and for a $500 diff I wasn't really fussed much. But for a $1500 diff that no one appears to have shaved before it wasn't a calculated risk, so Venom looked for another diff to play it safe.

Cheers

Bennie
 
If only wavetrac made diffs for subaru's i think they could be a really good compromise option.
 
sorry to dig up an old thread but is there any specific info on installing a 6sp sti front lsd into a dual range box?

I have heard you need to machine down the outside but cant find anything more specific than that
 
BeeJ said:
sorry to dig up an old thread but is there any specific info on installing a 6sp sti front lsd into a dual range box?

I have heard you need to machine down the outside but cant find anything more specific than that
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I think that is what Rally did. Check out his build thread. He was very impressed with the work done by the installers
 
Nothing specific I am aware of has been posted. I think the people who spend the time and money researching this and doing the R&D want to keep their intellectual knowledge to themselves. Don't be surprised if they don't give it out so others can benefit from their work and they miss out. I would suggest you contact Dave and he might want you to send him the gearbox and diff and he will return it ready to go. I don't the details of what was done to make it fit. I'm just glad that it does and that it works
 
Found a gearbox builder who's willing to do custom boxes in Perth.
Quite a private guy, extremely skilled and says if we supply the parts and it's possible for them to fit he can do it. He's done Subaru rally style boxes and is familiar with modifying them.
He isn't the cheapest but I'd rather pay for quality.

Llooks like Brett will be the first to get a box done I'm WA!
 
I have a Quaife diff in front that also needed to be shaved, not by much, only the head of the bolts holding the casing, sorry no pics...
 
And while this is dusted up, which front diff is the easiest to mount? Is it a job for a reasonably handy home mechanic?
 
Gearbox out job. You may have to set up the preload on the diff. You also need to ensure you have the right driveshafts for the centre you plan to use.
 
Rally said:
Nothing specific I am aware of has been posted. I think the people who spend the time and money researching this and doing the R&D want to keep their intellectual knowledge to themselves. Don't be surprised if they don't give it out so others can benefit from their work and they miss out. I would suggest you contact Dave and he might want you to send him the gearbox and diff and he will return it ready to go. I don't the details of what was done to make it fit. I'm just glad that it does and that it works
Click to expand...

There isn't really anything intellectual about machine "this area" "this amount"
I'd be happy to get those guys to do it but being on the other side of the country means its simply not economical to ship a gearbox and diff over east for machining and fitting...
 
Well there is because he knows and we don't! He didn't just pluck a number or something out of the air. Agree about the cost of freight though.
 
casperfromholland said:
And while this is dusted up, which front diff is the easiest to mount? Is it a job for a reasonably handy home mechanic?
Click to expand...

The front Quaife was mounted in 2005 by a mechanic but since then, I do the mechanic myself with sometimes the help of a friend that is mechanic.

The work is not very difficult if you are methodic and have the right tools, even the backlash is not that hard to do...
 
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