512TR Gearbox problem.

Don´t look on the miles you have to look on the drivers!

I saw a lot of cars which didn´t look low mileage when i reduce it to the driver seat…

20 years and 40.000 km how should it look, new?

edit: sorry, 28.000 km!

But you are right, it doesn´t look good!

 

And for the black 512 TR from Elite, i hope the cavallinos on the fender are only
stick on and not drilled...

 

Hi from Australia Alex,

Don't stress too much, the problems are easily defined for each model.

If you look to buy a late model (second half 1994 onwards) 512TR it will have the upgraded M diff installed. You won't break one of those diffs in either 512TR of 512M.

The wear on the gears comes up often but there is no definitive cure. I have a 512M here that came from Saudi Arabia and it has taken the hardness off 4th and 5th gears! Go figure.

I believe that this wear can be an oil deficiency issue of not using a good enough oil in the transmission. My 1988 Testarossa shows zero damage to all gears in the box, yet it regularly gets a good dose of throttle in all gears. It has sub 50k kms on it.

The thing that the M car is known for is having a larger quill shaft which isn't as flexible as the Testaross one, but is stronger. So the shaft itself doesn't break, but it has been known to snap the end off the main shaft of your gearbox.

Racing M cars in the 90's had a special quill shaft fitted to allow more flexibility yet retain the strength. These are still available for under $2k USD and it would only take about three hours to fit one of thee shafts. So a relatively easy fix.

So in short, your M has a super diff, keep good il in the transmission and change it as required, and do your quill shaft upgrade and you should get many, many happy miles out of it for very little mechanical issues.

 

Mine is for sale too ('92, red/black, powersteering, upgr diff + full upgr gearbox)

Looks indeed AWFUL ... How on Earth .....

 

Found THIS add in Kapaze.be (EU/Belgium) ....

Just like that ..... Euro 3000 for an unknown piece ... looks like a oem 512M diff ?
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Wow, better to spend 2.850 Euro on the well known Forza part…

 

Indeed !!!!

Including life-time warrantee ....

 

This is what a 512M diff looks like, has the oblong slots in the forging in front of the CW.
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Anyone interested in these oem F Diff Bulletins ?
View attachment ti30_23 512 TR Forged Differential.pdf
View attachment ti632_3 512Tr Differential Shims.pdf

 

Hi Mel,
I am planning to buy a 512TR, which will probably be a pre-94, in which case I'll pre-emptively fit a Forza diff carrier and new quil shafts. I saw where to order the Forza diff, but did not see a link / reference for the quil shafts?

Also, two things are not clear to me :

1) What was the initial gearbox issue that caused the failure of the seemingly unrelated 3 parts (diff carrier, C&P, and another I think).
Was it the gap that you photographed and that was due to incorrect assembly?
Just so that I know what to look at in a TR gearbox...

2) A reputed Ferrari specialist here in Paris says that when the diff fails, the car can still be driven (it just makes some noise) and does not cause any chain-of-events further damage (flying shrapnel for instance).

What is the opinion here?

Thanks,
Alex

 

512 Quill shaft (151651) - Detailed item view - Forza Components Ltd

 

if you go on driving with a broken diff the pressure to the left diff cover will be to high and this cover will brake. mostly then the CP also is not ok anymore. and if you are very unlucky the whole gearboxcase can get damaged

 

Correct Romano !

(At 1) -> This diff was created by well known factory ZF on specs, given bij Ferrari for the 365 with 300 HP's.
..............Installing this diff unchanged in cars with almost 400 HP's (25% more) was the big MISTAKE done by Ferrari technicians imo.

(At 2) -> Absolute NONSENSE of a dilletant " Ferrari Specialist" imo !!! The facts written in the threads here show different damages every time.

So, plan your next EO carefully and get an upgraded diff well beforehand ....

 

Re found this thread again! Very useful info !

http://www.ferrarichat.com/forum/boxers-tr-m/226140-tr-boxer-crown-pinion-solution.html

 

Should i plan with the diff and quil shaft upgrade also the crown and pinion update?

Round about 10.000 USD in parts, ouch…

 

but then you only have the original CP

I have let made 3 sets CP and all together it was about 25.000 €, but highest quality for my koenig competition.

the quil shaft was from robert hayden, australia. the diff also from australia, manufacturer was MODENA. but there are in this forum still 2 more manufacturers ( philwozza offers diff with livetime warranty )

 

I thought about diff and quill shaft from Forza and CP from Newman!

 

ONLY the diff upgrade is absolutely needed Christian, nothing else imo !!

 

A few people told me not to change the shaft as it is the "fusible link" when it breaks it doesn't destroy what is around it and prevents other more expensive parts from breaking.

 

I agree fully with THAT Todd ! Only exchange if broken ...

 

I also agree with this.
so if stronger shaft then also in the gearbox itself you have to change the main shaft ( 109716 ) with one made of much better material ( for example 18 Cr Ni Mo 7-6 )

 

So complete list would be:

-diff
-quill shaft
-cp
-main shaft

So if nothing is broken, i only have to change the diff,
but if i change more, i have to do all?

Any source for a better main shaft?

Greetings Christian

 

right, but use new screws for the crown gear to fasten to the diff

this depends on how much more horsepower you have and how you are driving with the original power. normaly the original parts except the diff are ok. better would be to use the stronger quill shaft from the later models ( diameter 19 mm instead of 17 mm ). this still is like a fuse.

but when you do this big job you just replace all bearings and check the synchro-rings and also have a look at the single gears because of pitting or even broken parts.

yes, I have let made some together with the CP and still have here 2 pieces. if interested send a PM.

 

I don´t want to add more power and i´m a gentleman driver with the 512 TR
but i like to know that the enginge and gearbox are "bulletproof"!

 

Simple: next EO (engine-out) inspect and take out the diff; replace diff only !