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Okay, I have got my car licenced & registered today, I am extremely happy with the way it turned out, but there is just one problem with it. It has an aftermarket LSD, that I think is a 2-way that sounds pretty nasty.

When turning, mostly parking style but also turning as normal, there is a knocking sound from the diff, that pretty much happens all the time. It just sounds really bad, and dosen't seem normal at all. It dosen't really do it in reverse either. It is fine in a straight line (makes take-off very good), but turning is another story. I don't know too much about them, but to me this seems like a bit of a problem!!! At first I thought it was maybe a bit tight or has locked up due to one wheel having to go further than the other, but I just really can't say for sure.

I was just wondering if anyone knows somebody that could help me out, preferably somebody with quite a bit of knowledge & experience to do with this sort of thing, so if you can it will be much appreciated. :D

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Yeah, I thought it was normal but it just sounds a bit *too* much, would like to get it checked out all the same. It seems more suited to drag car, there is no problem in a straight line.

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I believe it depends on the make/model of the mechanical diff as to how much noise it makes. Some mech diffs make no noise at all. But generally a 2 way will make more noise than a 1.5way ... (a 2 way will lock on acceleration and decceleration, a 1.5way only locks on acceleration).

:P

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Some, not all, make alot of noise. Two things I have found that make a difference:

1/ how new the diff is, and

2/ the weight of oil and how new it is.

Freshening up the oil can do wonders if it hasnt been changed in a while.

It would be worth taking a look just to make sure whoever complied it for you changed it anyway, as it should be done. Possible if they did do it they used a 'light' diff oil, which wouldnt help either.

I recently replaced my diff oil with a 140 weight, quietened it up a fair bit, but it hadnt been done in around 10,000kms.

If the oil is making no difference or not enough difference, it may be time to change the clutch packs in the diff.

If you go to stock diff, from a performance point, you WILL regret it. Mech diff makes a huge difference to the car when you are going hard, or even just taking off from the lights.

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I spoke to the import broker today, and while he said he isn't an expert on diffs he thinks it is also something to do with the oil. He will be speaking to someone next week about getting a good oil for it, and hopefully after that it will be okay. I probably would regret going to a stock one, but making turns just sounds very painful, and I can't really accelerate too much out of roundabouts, because it just dosen't feel right.

I wouldn't swap with someone if there is a problem with it obviously, but even after we try a new oil if it knocks too much for my liking I will probably switch it over.

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My car does the same. I own a Cefiro which has the same diff. I'm told it has an aftermarket LSD, havent looked as to what kind yet.

I makes some nasty noises when cornering at low speeds so im guessing it has a 1.5 or 2 way LSD.

i have just changed the oil, using what is specified in a GTR manual

HYPOID lsd GL-5

80w-90

I havent tested it out yet as the car is still on akle stands but will let you know this week if changing the oil has improved the noise

My car also has a Hicas lock bar and the camber is set at 1'5 degree's at the rear

Im not sure if this is adding to the problem

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Could it be generalised that most 1.5/2way diffs are probably not run in correctly when first installed. There's a couple of articles I saw a while back on running in the KAAZ LSD's. Takes about 30mins of driving in a figure 8 fashion to properly run in diff for smooth working - ie. minimal knocking. It also mentions that it's possible for diffs that weren't run correctly, that you can redo the procedure to smooth (reduce knocking) it out again. Takes a couple of dumps of diff oil too.

Some info here - http://kaaz-uk.com/faq.php

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I just took my Cefiro for a proper thrash after putting new oil into the gearbox and diff

It runs fine now, not a sound out of the bugger, sept for the sqealing of tyres as it goes round and round

figure 8's are fun even if you arent wearing in the diff

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