Few weeks ago I bought new afrer market differential to my 512tr and started to plan who or how to do the change. Friend of mine has done it several times and he promised to advice me enough to do it with my son and come to do measurement/ adjusting job when its ready for it. Today was the day to to take out the old diff and start to assemble the new one. My friend made some measurements, took side covers off and same time old diff went in two pieces, it was already broken !!! Everything else around diff looks to be ok, but big bang was close, really close!!!
Very lucky guy! I just did this thing to my boxer, so everything still fresh for me, although my diff was still ok. Preload setting is the tricky part lots of opinions (I have my own) Be sure to get new crown bolts (I used ARP) these are not reusable. Take pics of diff internals When disassembling, there is a right way to get the proper bias from the LS.
I am going to replace the diff on my 91 this summer when the engine is out for new belts I have already secured the billet case and new LS disks. Any tips or suggestions would be of great assistance.
First pic is how it looks when diff was still on its place Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Do you have a part no. for ARP crown bolts ? (couldnt find them at ARP site) My new diff is complete with inserts, and ready to bolt on.
you are very kucky that the left side cover was not broken and also no more damage happened so again: it is not a question IF the diff will break - only WHEN
These are the bolts I used, TurboJoe shared this info. Image Unavailable, Please Login Image Unavailable, Please Login
Adding the F PN for future searches (and the ARP Part #): Ferrari PN: 104310 Crown gear securing screw ARP Part #100-9908
tuplakoo, where did you buy your aftermarket diff please? I’m in the UK and saw adverts for a replacement diff a couple of years ago - which I now cannot find. I do see that Superformance offer a unit priced at £2250 plus tax.
OK - 10 mins after posting the above I found what I was looking for. It was Gripper that I looked at previously.
I understand that it happens. The question is why. Owning 4 Tr cars and one being a 750 hp car, it points to mechanical abuse. Its not a 2005 mustang that you can hammer. If you or the former owners would have treated the car like it should have been then this would not have happened. Brute strength carriers are made but not required for a guy that understands what is happening back there.
Misread the ARP PN from the pic -- should've written: Ferrari PN: 104310 Crown gear securing screw ARP Part #203-2802 (but the pic is not so clear for this so hope someone can better confirm)
Owners need to take care of their cars. Sometimes you are a victim of the previous owner. i get that. You do not deserve to own a TR if you do not understand what you own. You can tear it up by abuse that you may not even understand. There are delicate areas of these cars unlike other cars. Someone needs to post a do not thread about TR’s. I may if another does not get it and can step in.
If Steve had the time or thinks it is warranted to help others in the future that buy their first or second TR to save them some money and heartache, maybe he coul start a do's and do not thread for taking care of these cars. Steve I will pm you about this. I understand that some may disagree with me but I am just trying to help others so they don't see this problem occur. Plenty of high mileage cars out there that have never touched the differential and I don't think they just lucked out and got a better one than the next car. These cars just have a light duty case and couple that with a heavy car and jack rabbit takeoffs and jerking the car through the gears start the crack process on the casing at the welds. If none of this matters to you then just money up and get the Newman piece so you can hammer the car around without worry....at least in the casing. I have seen broken teeth on 2nd gear and so many abuse related problems. Ferrari's and Lamborghini's are mainly cruise/track cars and not meant for the drag strip or related.
I am the friend he is refering, this is my fourth car I am chaging diff, Owner does bolting, but I help and offer tools and take messurments/coloring. I currently runing out of peelable shimms and have try to contact "Forza Components" to get more, but no luck. Does anyone have information about Phil or other option for those great peelable shimms.
When I used the Forza peelable shim I needed to open up a couple of holes before using. Did you have this issue? Because of this I'd rather just have a new one cut. You can spec out the thickness of the peel too. Turbo Joe posted the vector artwork for the shim. I'll check my files for it. His file had the holes laid out correctly.
just now again in thailand and have no access to me documents in germany but you may find somewhere here for sure
Ferrari chose a crappy design when they put a weld in that location. Abuse makes it obvious, but the bad Ferrari design is still the root cause (pun intended) of these failures.