Has anyone had the dreaded transaxle/diff failure?

May be a silly question , but does the 512 trans shift better or is it just stronger than the regular TR trans.

 

Here's a copy of the communications - fyi.

(I'm going to do it next fall - cars getting close to completion for this summer to do it now).


Dear Mark,

For the 512 BBi application we will custom manufacture as there is very limited demand. This will require your gearbox and details of what problems must be solved and failures that have occurred. Any failed components will also assist in manufacturing an improved solution. The design and manufacture will be completed by Modena Engineering in Australia, which we are the authorized importer for the US.

I need more detail for the project before offering a time and cost estimate. For reference, complete gearbox conversions to race specification run between $10,000.00 and $35,000.00 depending upon application. A complete gearbox for a new application, from CAD file to manufacture, can take as little as one month.

Thank you for your inquiry.

Best regards,
Rob

Rob Schermerhorn
Delta Vee Motorsports LLC
10560 West KL Ave
Kalamazoo, MI 49009
847.638.4226
FAX 269.585.6013
[email protected]
www.deltavee.net

Then I received this email from Frank at Modena:

Its been a while since we have done one of these gearbox's we have done
a few for Ferrari challenge in Europe the price would be approx $11500
with the diff.
Regards frank.

Modena Engineering Australia P/L

Factory 2/11 Daniel Drive

CARRUM DOWNS VIC 3201

AUSTRALIA

Tel: +61 3 9782 4420

Fax: +61 3 9782 4260

 

Mine does...much better.

 

Was it due to a change in gear oil?

 

Good information here. What I am still confused on is this. Are all the Ferrari Testarossa and 512TRs up to 1993 prone to braking? Ir is it just the early model Testarossa pre 1991 on back that have this issue?

 

I agree 100% with testarob.....I replaced the gearbox in my '88 (when it broke) with one out of a salvaged '95 512M.... the difference is like night and day - smoother, stronger, lighter, better. No more crunching the gears from 1st to second and downshifts are an absolute breeze.

Doc

 

So the cost is $11,500 and you've got your self a rebuilt gearbox with a new carrier that will not break??

 

Trutlands sells them for $14K and change (exchange) but you will always have the 1st gear that can break anyway unless there's an update for that too?

 

Yesterday 04:48 PM
silvergts1998 Good information here. What I am still confused on is this. Are all the Ferrari Testarossa and 512TRs up to 1993 prone to braking? Ir is it just the early model Testarossa pre 1991 on back that have this issue?

All are susceptible to breaking up through transmission serial number 1512. SN 1513 and up were the machined housing rather than the welded housing. My understanding is this commenced with the 1994 model and continued with the 512M. I have no way to correlate the tranny SN with the VIN number or exact year model. Mine is #314 and is a 1992, VIN 92223. I believe the transmission SN's ran consecutively but there were breaks in the VIN numbers for other models of Ferrari's, i.e. 348, etc. The number is on the back side of the transmission housing down low.
Ron

 

So you're saying your 1992 has the bad carrier housing?

 

No, but I looked it over closely when I had the engine out by pulling the back of the trans/axle cover off. I worry about it as I do some hard acceleration in 2nd and 3rd gear but only after the clutch is fully out and going straight ahead on a hard, dry road. I'm told by the experts that this is not likely to break it. Doing burn-outs or having a spin-out on the track and not getting the clutch in quick enough is what I'm told breaks the differential. Still it's a concern and I don't have any idea how the prior owners treated it. The input shaft is the larger diameter that went in the later 512TR's, so that means someone probably broke it and replaced it. This is a fuse in the driveline that I now don't have.
Ron

 

What do you mean "not getting in the clutch in quick enough?" How would that break the housing?

 

Someone with some more knowledge than I needs to state this better, but what others tell me is this: When you spin out on a hard surface with power applied there is a great strain on the input shaft and differential housing. So disconnect the power by clutching it. Also I believe another factor is the 512TR has a very positive limited slip diff.

I may have stated this a little wrong and may get blasted. Hope someone will come in that has "been there and done that."

When you visually examine the diff housing you will see that the right side is very strong and the left side is the weak link where it is welded together.
Ron

 

As a 8 yr plus TR owner with 57,000kms on the car i still would like to know what these animals have done to break these things.
I find it hard to believe that 3 or 4 burnouts would ruin this on the TR....it must be more abuse to the car than anyone cares to lead on. Previous owners must have blasted these cars without proper warm up to the tranny often and driven them like a Mustang often with hard shifting.
Sorry to hear of the troubles some of you are encountering.

 

Realistically these cars should not have this issue ever taking the racing background into consideration and the cost of the cars. You should be able to beat it to death and it come back for more. My 71 challenger took a beating every time I dorve it, never broke. This is very disappointing and takes away from the ferrari experience IMO, almost makes me want to sell and pick up a 427 vette and not worry about anything breaking. Its a toss up if the good out-weighs the bad when you think of all the BS that goes along with ownership. Ive seen 550's with broken diffs and daytonas too so its not just the flat 12 guys.

 

As a preventive measure while things are still in one piece, why couldn’t you just open up the transaxle, say while doing an engine out service, take out the ring gear carrier, and re-weld it.
I assume the gear comes off the carrier, and I’d think a really good welding shop could gouge out the old weld, and then re-weld it with stronger material. Any warpage could be addressed by chucking it in a lathe and re-surfacing.
Of course opening the box wouldn’t be inexpensive, but I’ll bet the entire job would be a good deal less than repairing after the thing flew apart!
John

Ditto on the tuff Detroit iron! My hot rodded 67 Mustang was absolutely bullet proof!

 

As the saying goes, "...why jump out of a perfectly good airplane." And why tear apart a perfectly good differential/transmission. While a few have suffered catastrophic failure, let us remember that there were 7,000+ Testarossas/TRs produced. Based on the information gathered on F-Chat, the percentage that have failed seems miniscule. If 100 owners have experienced this disaster, then the odds are 100/7000+, or slightly greater than 1%. For those of us who drive our Testarossas with respect, as the high-speed straight-line cruisers that they are, it would seem that the risk of doing nothing is reasonable. Stated in the alternative, a definite expenditure of $15,000+ versus a maybe of $25,000 is a no-brainer for me. I play the odds, drive the car appropriately and not worry about it.

Perhaps the timing belts will snap at the precise time that the differential carrier fails! The odds of simultaneous failure are 1/70 * 1/70, or .0002 (.02%). If your belts have failed, you can forget about problems with the differential. Similarly, if you diff has failed, you can bet that your belts won't.

Jim S.

 

If not mistaken, the engine is ontop of the tranny, another 5/6 hr labour to take it off from what i understand and then another 6hrs to put it back on. THe piece cannot be rewelded, something about the heat and the metal then becoming weaker. Hence the 512M one piece unit upgrade.

 

You dont have to split the two to do the diff carrier and yes I was breast fed.

 

ahhh....

Interesting about the breast feed ..ROLMAO !

 

Big Red,
I've owned my '88 Testarossa since 1997 and i have put over 100,000km on it....but then I've driven it HARD with the odd burnout (now and then) heavy shifting and high rpms....I'm also on my second gearbox....and have replaced 3 clutches (the first one was right after buying the car), 2 stub axels, 1 imput shaft and numnerous head and valve gaskets.... SUfrfice to say its been expensive maintaining the car! But the fact is that some people just drive their cars harder and more agressively than others. Personally, i wouldn't call it abuse and i have never driven the car without properly warming up the tranny. I also own a highly modded C6 vette which i also drive VERY HARD - just last thursday I collaspsed a lifter and a piston at high rpm (near redline) in 6th gear (under 9 lbs of boost).... So bottom line is that these sort of mechanical problems are nearly ALWAYS to do with the way the car is driven.... Just know that if you're going to play your'e going to pay!

Doc

 

Its just a crappy part. End of story. When its goes fix it or dump the car. Or do the preventative thing and buy an updated unit now before the failure happends. YOU DO NOT NEED TO REMOVE THE ENGINE FROM THE CAR TO DO THE JOB!!! If other damage was caused to the trans (such as large chunks of metal damaging the gears) then the engine and trans need to be seperated and the entire unit checked out.

You can inspect the internals of the gear box without removing the engine as well. Just remove the left forward exhaust manifold, undo the engine mount and remove the side cover..everything is right there exposed for inspection. The only thing you can't see is the pump at the front of the gear box.

 

The difference here is you are paying to play. The story i keep hearing is new owners that have the car a short period of time and it happens to them. The fact that you are owning up to it, and fixing it is another story (your in a different class)....i think alot of people that own these things (most ferraris btw) keep them for short periods, beat them and then sell them....when they do get to owners that love them, they get the dreaded bill. Lets face it, there are cowboys in every brand not just ferrari's...you jsut hate hearing about it, and cant help but feel bad for a guy that spent 75K on his dream car since childhood, and then having to hear within a year or 2 that he needs to dump another 25K because a few previous owners never changed the tranny oil in 15 yrs.
BTW Doc, hows that project coming along ? You done yet ?

 

Not exactly the right application here, you are paying for a design flaw not to play. Playing is fun.

 

Quiet !