Fitted a LSD to my e85 Z4 3.0

So it was a used diff?
First of all pop the rear lid, measure backlash and do a wear analasys with ink.
That's something you always do when buying a used diff or installing an aftermarket one.
When you install a new diff in a previously unopened case (so crown&pinion stil factory fitted) you can get away with only a backlash measurement imho.
 
Ok, i will check these. Yes used diff. And probably a bit molested due to the supercharged z it was in. I still have my own diff in my storage.

What about the second sound? The clacking sound which seems to come from the center driveshaft. I can feel it somewhere behind the gearbox
 
Yes the second sound is the most disturbing.....
sounds coming from the rear when turning (slow turn but sharp turn) can only come from the diff (the inner diff; the lsd itself) or tyres.
Analyzing the wormgears in the diff itself might be very difficult.

Going downhill and getting noises can come from a number of things. Final drive gears, propshaft, gearbox, propshaft support bearing etc.

But to be clear: the shop that installed the diff only installed the complete lollypop from the other car? They did not physically install the lsd?
What might be a good idea is getting the lsd out of the lollypop and put it into your own old casing, if you can't localize&define the sounds to the propshaft or some bushing or so...
That way you know the crown&pinion are ok (I assume your old diff has reasonable mileage and has not been tampered with), you know the crush sleeve from the pinion shaft hasn't been tampered with (very important!), the bearings are ok etc etc etc.
Because the biggest uncertainty is that some other bloke has been there before. That can be a good thing.....and it can be a very bad thing.....

Be sure that your shop has experience with the bmw 188 diff in particular. The bearings are a hassle to get off with lots of potential risk for damage and they cant be bought new (at least, not easily).
Fitting a complete diff (the complete lollypop/casing) is a whole diffenent ballgame than fitting an acutal lsd into a casing.

For the swap you need new oilseals on the outgoing axles, and the rear lid paper gasket is not sold anymore so you have to use some blue silicone sealant.
The shop has to have special tools for fitting the lsd. (like a (preferably) very large hydraulic knive edge bearing puller and 3,5mm (3,5mm pin diameter that is) circlip pliers (hazet 1846A-4 or equivalent)_
 
GuidoK said:
Yes the second sound is the most disturbing.....
sounds coming from the rear when turning (slow turn but sharp turn) can only come from the diff (the inner diff; the lsd itself) or tyres.
Analyzing the wormgears in the diff itself might be very difficult.

Going downhill and getting noises can come from a number of things. Final drive gears, propshaft, gearbox, propshaft support bearing etc.

But to be clear: the shop that installed the diff only installed the complete lollypop from the other car? They did not physically install the lsd?
What might be a good idea is getting the lsd out of the lollypop and put it into your own old casing, if you can't localize&define the sounds to the propshaft or some bushing or so...
That way you know the crown&pinion are ok (I assume your old diff has reasonable mileage and has not been tampered with), you know the crush sleeve from the pinion shaft hasn't been tampered with (very important!), the bearings are ok etc etc etc.
Because the biggest uncertainty is that some other bloke has been there before. That can be a good thing.....and it can be a very bad thing.....

Be sure that your shop has experience with the bmw 188 diff in particular. The bearings are a hassle to get off with lots of potential risk for damage and they cant be bought new (at least, not easily).
Fitting a complete diff (the complete lollypop/casing) is a whole diffenent ballgame than fitting an acutal lsd into a casing.

For the swap you need new oilseals on the outgoing axles, and the rear lid paper gasket is not sold anymore so you have to use some blue silicone sealant.
The shop has to have special tools for fitting the lsd.
Click to expand...

Ok thanks for all the info!

For sure my diff is in better condition. It just has 70.000 km
 
also when you drain the oil, go through it with a strong magnet, see if you can find metal filings.
 
So Fanatic fitted an LSD to 2.5i with 190bhp. It works despite relatively low power and torque. I was seriously considering to fit one to my car - 2.2 with 170bhp. But I was disadvised since the car lacks power and torque and I would be only putting too much strain on the engine. Was is your perspective on this matter? Anyone fitted one on 2.2?
 
An lsd doesn't put any extra strain on the engine. The only thing it basically does is stop the inner wheel from spinning when accelerating (in a corner or on a straight).

It depends on the power of the car, your driving style and your expectiations of the car if you need an lsd or not.
I mean the 3.0si with 265bhp has no lsd from factory (probably to cut cost and the misconseption back in the days that traction control could replace a lsd :lol: ) whereas cheap mazda mx5's all are equipped with lsd's in one form or another (torsen, viscous, clutch), with sometimes only 110bhp or so.

But it's a mod you purely do for yourself. You have to be annoyed by esp/dsc kicking in, loosing traction on manhole covers (not to mention in hairpins in the alps..) etc.
I mean there is nothing visible on the outside, so this mod has 0% 'streetcred' if you know what I mean.
 
The lsd strains the car no more than any other lively driving. But adding it does give a bigger smile on your face as you start feeling like a drift king on slippery roads! Of course more power is welcome but you can still have fun with 200hp ;)
 
True. But getting that outer wheel to spin and most of all to keep spinning you need torque. My friend is complaining over his Z3 2.8 with 190bhp and LSD. That's what got me thinking.
 
Lack of power :D He complains he needs to be carrying a lot of speed into a corner and be quite aggressive to keep it sideways. Once you run out of torque there's no other option than straighten the car. On 3.0 you still have some hump to add some more spinning to rear wheels.
edit: A lot of people are installing LSD on 3.0. But virtually no one with LSD on 2.2.
 
If you can't get it sideways you don't know how to drift ;)
Just lift the throttle and immediately floor it again to upset the balance of the car (or use the clutch of that) and you'll get any rwd sideways in a corner. Especially in the wet.
Maybe not a thing to do on the public road, as it can easily end in tears.... ;)
 
I don't think you need that much torque for it?
Most people apply too much torque/throttle (and wreck their car in the process.... :? )
At least in the corners.
 
RenoRaines said:
It's not about getting it sideways but keeping it there.
Click to expand...


Once you break traction you should be fine keeping it sideways with an LSD. If he can't do it in his Z3 he must just be rubbish :poke:

As already been said a mazda MX3 has an lsd and I've spent a day drifting those on a track without a single problem. In fact it's was great fun for drifting.


Get one fitted to your 2.2, you won't regret it. :thumbsup: :thumbsup: :thumbsup: :thumbsup:


Plus you can remove it when you come to sell the car and probably get a good portion of your money back.
 
Yorkie Z said:
Plus you can remove it when you come to sell the car and probably get a good portion of your money back.
Click to expand...

These mods hold their value better in general than the car if you sell them seperately :wink:
 
So a bit extra news on the sounds after the LSD install. Apparently the second and more serious one came from the driveshaft not being screwed in correctly. Thank god I got to it in time before something broke! Damn mechanics...

The sound when putting gear into first as I have read is a common sound that most if not all cars with wavetrack and mfacory lsds' have. So nothing worrying.
 
Fanatic said:
So a bit extra news on the sounds after the LSD install. Apparently the second and more serious one came from the driveshaft not being screwed in correctly. Thank god I got to it in time before something broke! Damn mechanics...

The sound when putting gear into first as I have read is a common sound that most if not all cars with wavetrack and mfacory lsds' have. So nothing worrying.
Click to expand...


Glad the first problem is sorted mate. The second problem is Backlash like I said before. You won't have I problem with it but if it was done properly it would be there in the first place. Give your guy who fitted it a slap
 
If it is backlash he has a very big problem as there is no real way to correct that.
The only way is to use circlips in different thicknesses...... try to get hold of those!!

If he has a backlash problem there might be a number of ways how the previous installer has made a faulty install (switched bearing races.... switched circlips... tampered with the alignment of the pinion etc etc... no way to tell).

Anyway it is the first thing you check when you install a diff. It's probably in the manual too with the correct tolerances.
I checked the size of my diff too with the crown gear offset and compared it to the original bmw diff prior to install to see if the manufacturer got his work done right (which was the case, after I torqued the bolts on the inner diff). I don't remember if I used a normal style micrometer for that or a height gage.
 
Reading this thread

http://www.e90post.com/forums/showthread.php?t=409095

the guy tested everything and still had the thump.

And more specifically in this post

http://www.e90post.com/forums/showpost.php?p=17653176&postcount=162

it is clear that the thump will always be there more or less.

So if this does not create a problem (which after reading a lot, I understand it doesn't) there is no reason to lose my sleep over it. It is minor and not always.

The mechanic that installed it on mine, installed it also on the previous owner. Also the same installation was made on a 335 and Z4 coupe these days, with measured backlash and they also have the thump.
 
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