hi only putting this up because im sure all the auto 75s had lsd if so here is the cheapest lsd your gunna get
http://cgi.ebay.com.au/Alfa-Romeo-75-Automatic-Transmission-/360359379103?pt=AU_Car_Parts_Accessories&hash=item53e717c09f
Interesting looking unit. Anyone know how these things are put together? Is this a way to get a separate transmission and diff (and throw the former away, but mount something else up? Not personally interested in doing that - just curious.
you just pull the diff out and then put it into ur manual gearbox, well thats what we did anyway, i sent the dude a email asking if he would just pull the diff out but im waiting to hear back, as i dont really need it i have put it up but if know is getting it i prob will, never hurts to have a spare
Hi guys,
Thought I would get peoples experiences with diffs and gearboxes here.
From what I understand, you cant just swap diffs between gearboxes without issues. The gearset is seperated in the middle which the input and output shafts go through the bulkhead. The distance from this bulkhead back to the pinion is what sets the back lash for the diff. There are a number of spacers from memory that keep the 1st, 2nd, 3rd, 4th in the correct position as well as the crown wheel + pinion in the right position so that it meets properly. By swapping the diffs without resetting the gearset with the correct spacing, wouldnt this result in an early end to the diff? And what about the difference in the number of teeth in the cw + p that comes with different final drive ratios??
Correct me if I'm wrong but I always thought Vin or Benincas were the ones to see when it comes to swapping diffs to avoid a gearbox full of marbles at the end of a spirited drive
Quote from: Darryl on May 04, 2011, 08:12:11 AM
Interesting looking unit. Anyone know how these things are put together? Is this a way to get a separate transmission and diff (and throw the former away, but mount something else up? Not personally interested in doing that - just curious.
I'm very interested in trying something like that - I'm of the understanding that the auto box is a zf unit of some kind... but I vaguely recally the diff is a fairly tall ratio. I'm looking at using the de-dion in something that doesn't lend itself to a transaxle, and the auto diff might be an easy way to sort the brakes.
Dehne, did you win the ebay auction?
From the research I've done, the LSD doesn't fit the manual transaxles.. same plates as the 116 and 115 LSDs though.
interestingly it the diff section can be unbolted from the auto-tragic gearbox...
Quote from: deano on May 04, 2011, 03:20:05 PM
Hi guys,
Thought I would get peoples experiences with diffs and gearboxes here.
From what I understand, you cant just swap diffs between gearboxes without issues. The gearset is seperated in the middle which the input and output shafts go through the bulkhead. The distance from this bulkhead back to the pinion is what sets the back lash for the diff. There are a number of spacers from memory that keep the 1st, 2nd, 3rd, 4th in the correct position as well as the crown wheel + pinion in the right position so that it meets properly. By swapping the diffs without resetting the gearset with the correct spacing, wouldnt this result in an early end to the diff? And what about the difference in the number of teeth in the cw + p that comes with different final drive ratios??
Correct me if I'm wrong but I always thought Vin or Benincas were the ones to see when it comes to swapping diffs to avoid a gearbox full of marbles at the end of a spirited drive
Yes Deano - correct. The diff itself is an integral part of the gearbox setup as the crown wheel bolts to it. Not setting the pinion up correctly when you install an LSD is risky.
There no issue with the different final drive ratio though (at least in my experience) as you re-use the original crown wheel. What you're actually swapping is the LSD diff centre. There are however two different sizes of stub axle; a smaller pre-twin spark 4-cylinder one which is not suitable and a larger type used on twin sparks and V6 cars which you need. These can be hard to find. It is possible to use the larger stub axles and the corresponding carrier in an earlier transaxle but some adaptation may be needed. Vin and Joe know what is needed. I guess Hugh would as well.
Quote from: LaStregaNera on May 04, 2011, 05:39:03 PM
From the research I've done, the LSD doesn't fit the manual transaxles.. same plates as the 116 and 115 LSDs though.
interestingly it the diff section can be unbolted from the auto-tragic gearbox...
Maybe people say that because of the stub axles? I've had two done in the past, one an early 4-cylinder transaxle and the other a late GTV6 one. It's not the rear diff section you want, it's actually the diff centre. It's the same unit (I think by ZF but dont quote me) as fitted to 2 litre 105's hence the same plates.
no i have not even looked at it again since i started this thread
Quote from: aggie57 on May 04, 2011, 05:51:03 PM
Quote from: LaStregaNera on May 04, 2011, 05:39:03 PM
From the research I've done, the LSD doesn't fit the manual transaxles.. same plates as the 116 and 115 LSDs though.
interestingly it the diff section can be unbolted from the auto-tragic gearbox...
It's not the rear diff section you want, it's actually the diff centre. It's the same unit (I think by ZF but dont quote me) as fitted to 2 litre 105's hence the same plates.
For the project i'm looking at, unbolting the rear diff is perfect... as long as it's possible to put a yoke of some description on the pinion shaft.
Quote from: LaStregaNera on May 05, 2011, 08:42:25 AM
Quote from: aggie57 on May 04, 2011, 05:51:03 PM
Quote from: LaStregaNera on May 04, 2011, 05:39:03 PM
From the research I've done, the LSD doesn't fit the manual transaxles.. same plates as the 116 and 115 LSDs though.
interestingly it the diff section can be unbolted from the auto-tragic gearbox...
It's not the rear diff section you want, it's actually the diff centre. It's the same unit (I think by ZF but dont quote me) as fitted to 2 litre 105's hence the same plates.
For the project i'm looking at, unbolting the rear diff is perfect... as long as it's possible to put a yoke of some description on the pinion shaft.
Sorry, in that case I can't help. Ask Hugh at Monza. He'll know.
Thanks Alister, that makes a bit more sense.
I was originally going to put my 3.54 centre into an open alfa 90 super box but Ive since got my hands on a TS box which is sitting in the garage needing 3 sinchros and 2 extra diff shim plates. It about finding the time to do it atm