ZFQ Transaxle failure

[Joe]

Rather distressing as my car is spec'd for a DG300 (expensive) or a ZFQ and has a little more power and torque (540hp, 495 tq) and a bit more rubber in the back (27.0x14.0x15) than David's.

From what I'm gathering in this thread and David's last post summation, there is a ZFQ with the alloy endplate (the one that had an unfortunate failure), and the RBT Transmissions ZF-based box with a cast iron endplate and beefed up internals/webbing (the replacement for the zfq)? Can someone shed some light on that please, thanks.

Edit: I just read the for sale post by David. I understand now, but any other info wouldn't hurt. Cheers.

 

[Seymour Snerd]

....Rather distressing as my car ... has a little more power and torque (540hp, 495 tq) and a bit more rubber in the back (27.0x14.0x15) than David's. .

Yes, well, you're not the only one, believe me.

....there is a ZFQ with the alloy endplate (the one that had an unfortunate failure), and the RBT Transmissions ZF-based box with a cast iron endplate and beefed up internals/webbing (the replacement for the zfq)? Can someone shed some light on that please, thanks.

Edit: I just read the for sale post by David. I understand now, but any other info wouldn't hurt. Cheers.

It makes more sense to think of the ZFQ as a recent replacement for (or better yet a competing alternative to) a ZF, and of RBT as the manufacturer and supplier of the ZF.

Similarly I'm not sure it make sense to say the RBT ZF has "beefed up internals/webbing". IOW, "beefed up" relative to what? It is a ZF. Is it "beefed up" relative to those manufactured in Germany in the 60s? I don't know.

re: "any other info wouldn't hurt;" what information are you looking for?

 

[Joe]

You've answered all my questions. Thanks.

 

[Charlie Farley]

Strange that this is the only failure posted on this forum.
If it was a common problem, you would have expected more by now.
After all, the zfq has been fitted to many cars for quite some time .
I hope the driver isn't being economic with the truth.

 

[David C. Treichel]

Strange that this is the only failure posted on this forum.
If it was a common problem, you would have expected more by now.
After all, the zfq has been fitted to many cars for quite some time .
I hope the driver isn't being economic with the truth.

No BS here, take it for what it's worth.

I'm sure there are cars out there with these transaxles that are fine, even when raced. I certainly didn't want my for sale thread to start a panic. For all I know it could be a once in a lifetime opportunity.

It makes me wonder though why the new ZFQ's have been redesigned (or so I have heard) with a thrust bearing right next to the pinion.
Can anyone confirm this? Or was I given incorect info. If so I apologise.

Dave

 

[Tom]

It would be nice if Quaife commented on this thread, and confirmed that there was or was not a redesign.

Of course, if they have redesigned, it's likely some people are going to be anxious about their 'boxes.

 

[Tom Leonard]

It would be nice if Quaife commented on this thread, and confirmed that there was or was not a redesign.

Of course, if they have redesigned, it's likely some people are going to be anxious about their 'boxes.

I shot an email off to Chris Melia and he promptly replied that he would be speaking with Quaife when they return from holiday and would comment then.

 

[Gord Zonailo]

Hi David, Sorry to hear of your ZFQ failure. I have a Quaife ZFQ no. 64 that was purchased in March 2010 but has not been installed yet. I will be using a 427 cu in stroked 351, aluminum engine in a CAV bodied GT40, mainly for open track events, so I am very interested in the circumstances and potential fixes before the installation.

What number is your transaxle and when was it purchased?

A lot of people who purchased the ZFQ's are interested!!

Gord

 

[Mike Drew]

Just FWIW, the current-production ZF gearboxes from RBT are philosophically similar to the 1960s and 1970s (Pantera) versions, but they are completely different internally, with virtually no parts interchange other than a few gaskets and bearings. They are actually built to the later, and perhaps a bit stronger, BMW M1 specification.

Ford determined quite early on that the original ZF Dash-0 wasn't up to the task of absorbing 500-ish ft/lbs of torque from the 427 side-oiler, which is why the T44 came into being. The Dash-1 (as used on Mangustas and early Panteras) was stronger/improved, and the Dash-2 (most Panteras) stronger and better still. Even though a new RBT gearbox is (supposedly) a bit stronger than a Pantera Dash-2, I would still say that it would be the weak link if you really ratcheted up the horsepower. (Well, more accurately, the torque).

I plan to go with a Pantera ZF and a 331-inch stroker small block in my someday-Superformance GT40. That's going to give me way more speed (and more fun) than I'd ever need, and the gearbox will live forever.

 

[Jim Rosenthal]

My car has the BMW M1 spec gearbox- it was an unused M1 spare and had BMW parts tags on it, which I wish I'd saved.

What is the internal difference or differences in the M1 transaxle that make it stronger? I know, by the way, that the trunnions for the external clutch throwout are deleted by ZF in the M1 box, because in order to fit the external slave cylinder system, Ron had to have the clutch throwout shaft trunnions made and installed. The M1 transaxle seems to be set up for an internal hydraulic release bearing, from the factory.

 

[David C. Treichel]

Hi David, Sorry to hear of your ZFQ failure. I have a Quaife ZFQ no. 64 that was purchased in March 2010 but has not been installed yet. I will be using a 427 cu in stroked 351, aluminum engine in a CAV bodied GT40, mainly for open track events, so I am very interested in the circumstances and potential fixes before the installation.

What number is your transaxle and when was it purchased?

A lot of people who purchased the ZFQ's are interested!!

Gord

Gord, The number that is stamped in the case on top: E62G 004

Not sure when it was purchased, we aquired the car in July of 2010.

Dave

 

[Gord Zonailo]

Thanks for your reply and info David. It appears that yours may be number 4 of the production runs??

Mine is marked E62G 064 V9 and is supposed to have the Superfinish treatment on the gear sets.

Gord

 

[Jack Dunn]

Jim,

I spoke with Oliver Ring (of RBT) at the PRI show a few weeks back and asked him about the differences between the Pantera ZF and the RBT/M1 ZF transaxles.
Among other things, the RBT/M1 external transaxle case castings were redesigned and strengthened. You can compare the two castings and see a lot of obvious differences externally.
Since I chose a new RBT for my Superformance GT40 behind a 630 hp 440" clevor engine (with 14" wide rear Avons), I asked about the RBT's strength and durability behind a big HP/torque motor.
Ring pointed out that Saleen used the RBT transaxle in the 550hp 427" S7 as well as the 750hp S7 turbo. And he reported no transaxle breakages in either of these applications. Pretty amazing.
In fact, the only weakness in either version ZF he mentioned seeing was when a Pantera is put into reverse and the driver drops the clutch and drives it backwards at full throttle! He's seen it more than once, surprisingly enough.

Jack

 

[Kelly]

Jim, In fact, the only weakness in either version ZF he mentioned seeing was when a Pantera is put into reverse and the driver drops the clutch and drives it backwards at full throttle! He's seen it more than once, surprisingly enough. Jack

Whoops, I guess I'm going to have to stop doing that now :laugh::lol:

Best,
K

 

[Jim Rosenthal]

S--t, and I was looking forward to driving backwards at full throttle - sort of a metaphor for how life is going sometimes......

Well, I am glad I have the more robust version of it, although to tell you the truth, it is probably wasted on me...I am not the most aggressive driver these days, and the last engine I blew up was years ago. I haven't hurt the Tremec in my Cobra yet, and I drive that harder than I drive anything else. I'll have to ask Ron about the differences between the various ZF transaxles. If I have got this right, the BMW M1 was the last production car made with the ZF 5DS25 transaxle- after that they were made for spares.

 

[wanni]

I remember Wanni caught some serious flak for asking about the development process on this 'box.

Now I am smiling. Ah.Ah.Ah

 

[Keith]

I remember Wanni caught some serious flak for asking about the development process on this 'box.

Please don't start all this shite again. Historically it was purely a matter of forum etiquette. As a respected gearbox expert Wanni was always entitled to say whatever he wanted to in the appropriate place on GT40's but he deliberately chose not to.

Ends...

 

[Ron Earp]

Please don't start all this shite again. Historically it was purely a matter of forum etiquette. As a respected gearbox expert Wanni was always entitled to say whatever he wanted to in the appropriate place on GT40's but he deliberately chose not to.

Extremely well stated and accurate.

 

[wanni]

Got the message.
Good bye.

 

[TimM]

What options would you have for something in the range of 800 hp?