More Camaro issues. This time the transmission.

No, I'm talking the F-body's T-56. The failures you're talking about weren't all that common and were mostly on the first versions to have said features. As for the power capacity, they were rated at 450lb/ft (more than Ford's, only the Dodge version was rated for more from the factory) but they can and will hold much more than that.

Rated? Sure. Would they do it? Not stock.

More seriously, GM T-56s would often wipe their synchros in less than 40K. There's something called the "drill mod" that must be applied.

I commend this thread to your attention: http://www.camaros.net/forums/showthread.php?t=142300&highlight=T56

As for how I know, at one point I was considering installing a GM T56 out of a Camaro into an XJ6. It would have fit with some sledgehammer encouragement, but I decided against it (due to interior considerations). However, I did do quite a bit of research before getting started and the amount of problems people were having with the F-Body T56 were boggling.

I'd also like to add this comment from the Camaros.net drivetrain forum from a discussion of TKO600 versus a T-56:

Rodder said:
The downsides of the T56 that I know of:
- it's only rated for 450 ft-lbs. You can built it up for >1000 ft-lbs with the right components (you'll be running dog-clutch gears at that level tho--no syncros).
- several components in F-body T56's are really fragile and will bend or break if you beat on the shifter too hard. It's a little under $1k parts+labor to have one rebuilt with all that junk upgraded. Most T56 failures are one or more of these parts.
 
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Rated? Sure. Would they do it? Not stock.

I personally helped install an LS1 swap into an RX-7 and he has put 60k miles on it since the swap, takes it racing every month as well as does drift events every month. Now I'm not sure if you're familiar with the strain drifting has on driveline components but between clutch kicking, wheel hop, etc. I should also mention he's putting down 520whp by the way. Not a single failure of any GM parts. In fact the only failure was an aftermarket clutch but that was a defective part to begin with.

More seriously, GM T-56s would often wipe their synchros in less than 40K. There's something called the "drill mod" that must be applied.

I commend this thread to your attention: http://www.camaros.net/forums/showthread.php?t=142300&highlight=T56

Yes because a clutch hydraulics issue in which the clutch isn't fully engaged when people are shifting is clearly a fault of the transmission. Do that to any transmission and it'll show the same faults.

As for how I know, at one point I was considering installing a GM T56 out of a Camaro into an XJ6. It would have fit with some sledgehammer encouragement, but I decided against it (due to interior considerations). However, I did do quite a bit of research before getting started and the amount of problems people were having with the F-Body T56 were boggling.

Considering most LSx swaps use F-body T-56's I just can't see where these problems are. They hold up to insane amounts of abuse. The only real issue with them is that the factory shift action was one of the worst in human history but that was solved with some cheap aftermarket parts.
 
I personally helped install an LS1 swap into an RX-7 and he has put 60k miles on it since the swap, takes it racing every month as well as does drift events every month. Now I'm not sure if you're familiar with the strain drifting has on driveline components but between clutch kicking, wheel hop, etc. I should also mention he's putting down 520whp by the way. Not a single failure of any GM parts. In fact the only failure was an aftermarket clutch but that was a defective part to begin with.

Then he must have been lucky as half the people I know with a GM T56 have had to have transmission repairs done - most recently my friend with his <40K old '04 GTO, whose synchros went out for no apparent reason - and he *doesn't* race.

Yes because a clutch hydraulics issue in which the clutch isn't fully engaged when people are shifting is clearly a fault of the transmission. Do that to any transmission and it'll show the same faults.

It is part of the transmission system as shipped by GM. Also, most post 1980 manual RWD cars incorporate such a damper and they don't have those problems.

Considering most LSx swaps use F-body T-56's I just can't see where these problems are. They hold up to insane amounts of abuse. The only real issue with them is that the factory shift action was one of the worst in human history but that was solved with some cheap aftermarket parts.

Why don't you cruise through the Camaro forums? You'll see lots of discussions about how the T-56 has failed. Some people seem to get good ones but a lot of them seem to be problematic even at stock power levels.

Then flip over to the Mustang Cobra forums where the only failures seem to be with guys making stupid levels of power.

***

I should note that I have a GM 700R4 automatic transmission in my Jaguar XJ6 Series III (ironically enough, out of an F-Body). Now, while it is a good transmission overall, there are some places where GM got cheap here too - which is why it's been upgraded with all the usual bits - Kolene steels, Corvette governor, shift kit, etc., etc. None of which GM offered for their lower level cars, which is why there's a huge aftermarket for their transmissions, among other reasons (because they do fail due to some of these issues). I also recently had to rebuild the factory 4L80E in the XJR because the GM solenoid pack failed - and it's not anywhere near the "maximum rating" for a 4L80E.
 
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Then he must have been lucky as half the people I know with a GM T56 have had to have transmission repairs done - most recently my friend with his <40K old '04 GTO, whose synchros went out for no apparent reason - and he *doesn't* race.

The GTO's are Tremec units, but they should last just as long if not longer considering they were improved upon. My guess is that your friend wasn't shifting properly.

It is part of the transmission system as shipped by GM. Also, most post 1980 manual RWD cars incorporate such a damper and they don't have those problems.

If the clutch isn't fully engaging in time then that will kill synchros. It's simple logic here. The GM hydraulics were shitty but the transmissions weren't.

Why don't you cruise through the Camaro forums? You'll see lots of discussions about how the T-56 has failed. Some people seem to get good ones but a lot of them seem to be problematic even at stock power levels.

Almost always the driver's fault. Have you met the average Camaro driver?

Then flip over to the Mustang Cobra forums where the only failures seem to be with guys making stupid levels of power.

They're no stronger than the Camaro T-56.
 
I should note that I have a GM 700R4 automatic transmission in my Jaguar XJ6 Series III (ironically enough, out of an F-Body). Now, while it is a good transmission overall, there are some places where GM got cheap here too - which is why it's been upgraded with all the usual bits - Kolene steels, Corvette governor, shift kit, etc., etc. None of which GM offered for their lower level cars, which is why there's a huge aftermarket for their transmissions, among other reasons (because they do fail due to some of these issues). I also recently had to rebuild the factory 4L80E in the XJR because the GM solenoid pack failed - and it's not anywhere near the "maximum rating" for a 4L80E.

How on earth can a solenoid pack be attributed to torque capacity? They're entirely independent of each other. That's like blaming a slave cylinder failure on a car having too much HP, they aren't any more stressed by differing power levels.
 
The GTO's are Tremec units, but they should last just as long if not longer considering they were improved upon. My guess is that your friend wasn't shifting properly.

Then pray explain why he has never had this happen on any other manual vehicle. If it was driver technique, shouldn't he have destroyed other transmissions as well?

If the clutch isn't fully engaging in time then that will kill synchros. It's simple logic here. The GM hydraulics were shitty but the transmissions weren't.

They're part of the system as GM shipped it. It would be GM's fault for the transmission's self destruction.

Almost always the driver's fault. Have you met the average Camaro driver?

I live in Texas. What do you think? :p

They're no stronger than the Camaro T-56.

The Mustang units may be rated no higher than the F-Body ones, but they had a much lower failure rate than the F-body does. Why is that? It can't be the drivers, as they're much of a muchness with the F-Body owners.

I also believe you need to talk to someone who runs a transmission shop - I have one for a client and he confirms all sorts of nastiness with the GM boxes. Other transmission shops have added their own notes as well. I note you haven't said one word about GM's prior history with the T-5 failures, either.
 
How on earth can a solenoid pack be attributed to torque capacity? They're entirely independent of each other. That's like blaming a slave cylinder failure on a car having too much HP, they aren't any more stressed by differing power levels.

It's not. I was pointing out that my XJR doesn't put out anywhere near the nominal torque capacity of the 4L80E, so the the solenoid pack failing could not even remotely be attributed to that (if you were so inclined to make such a specious argument).
 
Epic debate is epic.

You must be new here. Boring argument about transmissions is boring.

Bring up HP/L and we'll have some fun.
 
Then pray explain why he has never had this happen on any other manual vehicle. If it was driver technique, shouldn't he have destroyed other transmissions as well?

What other manual cars has he owned? High torque cars like the GTO will exacerbate any improper driving habit.

They're part of the system as GM shipped it. It would be GM's fault for the transmission's self destruction.

It's a clutch problem not a transmission issue. As I said the F-body transmissions themselves are more than up to the job. They do perfectly fine in other cars.

The Mustang units may be rated no higher than the F-Body ones, but they had a much lower failure rate than the F-body does. Why is that? It can't be the drivers, as they're much of a muchness with the F-Body owners.

I also believe you need to talk to someone who runs a transmission shop - I have one for a client and he confirms all sorts of nastiness with the GM boxes. Other transmission shops have added their own notes as well. I note you haven't said one word about GM's prior history with the T-5 failures, either.

I have first hand experience with these transmissions. I take that as paramount compared to someone who may or may not be biased, and when it comes to a Ford or GM thing I don't trust anyone unless I know them personally.

I don't comment on T5's because my only experience with them are fully built units in track cars.
 
What other manual cars has he owned? High torque cars like the GTO will exacerbate any improper driving habit.

IIRC, he previously had a Supra and a Factory Five Cobra replica that ran the pre-blower Mustang Cobra powertrain.

It's a clutch problem not a transmission issue. As I said the F-body transmissions themselves are more than up to the job. They do perfectly fine in other cars.

Sort of. Why don't you go look at those fora again? They disagree about it being up to the job. In addition, D&D Transmissions is making a fortune off all the Viper-spec T56s they're selling to people wanting to convert their older Chevies.

I have first hand experience with these transmissions. I take that as paramount compared to someone who may or may not be biased, and when it comes to a Ford or GM thing I don't trust anyone unless I know them personally.

Heh. The former part is not a bad idea, the latter part is just funny.

Just how much experience do you have with the GM T56?

I don't comment on T5's because my only experience with them are fully built units in track cars.

Mmm-hmm. Go search those fora.

HP/L is the most worthless statistic ever.

Only when you're on the losing side because you have a car. :D

150 HP/L anyone?

Ninja_ZX_14_white+red.jpg
 
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IIRC, he previously had a Supra and a Factory Five Cobra replica that ran the pre-blower Mustang Cobra powertrain.

My point stands then. The Supras weren't ever high-torque cars and they had Getrag transmissions which are generally bulletproof.

Sort of. Why don't you go look at those fora again? They disagree about it being up to the job. In addition, D&D Transmissions is making a fortune off all the Viper-spec T56s they're selling to people wanting to convert their older Chevies.

Well with the 3rd gear slider changed out and the 2-3 shift fork replaced the F-body transmissions are capable of over 650lb/ft so it's more people not knowing the solution or not wanting to open up a manual box, which I don't necessarily blame them for.

Heh. The former part is not a bad idea, the latter part is just funny.

Just how much experience do you have with the GM T56?

I used to have an RX-7 with one, as well as more friends with them than I can count. In my circle the LSx swap is incredibly popular.

Mmm-hmm. Go search those fora.

I refer you to my point earlier. Also we are not speaking Latin, it's forums. :p

Only when you're on the losing side because you have a car. :D

150 HP/L anyone?

Only matters in racing series where displacement is limited. ;)
 
My point stands then. The Supras weren't ever high-torque cars and they had Getrag transmissions which are generally bulletproof.

Doesn't explain the FF Cobra not having problems, though.

Well with the 3rd gear slider changed out and the 2-3 shift fork replaced the F-body transmissions are capable of over 650lb/ft so it's more people not knowing the solution or not wanting to open up a manual box, which I don't necessarily blame them for.

Yeah, but we're talking about stock power levels - and for various reasons the F-body boxes have issues, as reported by their owners.

I used to have an RX-7 with one, as well as more friends with them than I can count. In my circle the LSx swap is incredibly popular.

Similar experiences down here, but the T-56 isn't quite as highly regarded down here as it seems to be up there.

I refer you to my point earlier. Also we are not speaking Latin, it's forums. :p

The Latin would be "foris," actually. :may:


Only matters in racing series where displacement is limited. ;)

Not really, it also matters on the street. :D With motorcycles, anyway.
 
Doesn't explain the FF Cobra not having problems, though.

Mod motors aren't exactly the torquiest either. I figured it was implied.

Yeah, but we're talking about stock power levels - and for various reasons the F-body boxes have issues, as reported by their owners.

Some people had problems with the g50 at stock power levels... And it's one of the strongest production car transmissions ever made. The T56 is good stock, I was just pointing out that two parts would put the power capacity well over anything you'd see from the factory cars and that is WITH stock synchros.

Similar experiences down here, but the T-56 isn't quite as highly regarded down here as it seems to be up there.

My friends in Texas disagree. :p

The Latin would be "foris," actually. :may:

It's fora. I'm willing to put money on it.

Not really, it also matters on the street. :D With motorcycles, anyway.

When it comes to cars it's irrelevant on the street. For example the LS motors may be large and slightly lower HP/L than most performance motors but they're also smaller externally and lighter than them so they make up for it. *shrug* When it comes to bikes it doesn't matter, Italian v-twins only for me.
 
Mod motors aren't exactly the torquiest either. I figured it was implied.

So, you're saying that a GTO with 365ft-lb@4000rpm is somehow less destructive to the transmission and is torquier than a 5.4L that makes 385ft-lb? :blink:

Some people had problems with the g50 at stock power levels... And it's one of the strongest production car transmissions ever made. The T56 is good stock, I was just pointing out that two parts would put the power capacity well over anything you'd see from the factory cars and that is WITH stock synchros.

Assuming it didn't already wipe those out. :p

My friends in Texas disagree. :p

Let me put it to you this way. One of my clients is an actual Government Motors dealer, and their service manager told me about how they'd had to replace lots of T56s under warranty.

It's fora. I'm willing to put money on it.

I may type corrected on this one, my Latin isn't the best and I don't really care enough to go look it up. :dunno:

When it comes to cars it's irrelevant on the street. For example the LS motors may be large and slightly lower HP/L than most performance motors but they're also smaller externally and lighter than them so they make up for it. *shrug* When it comes to bikes it doesn't matter, Italian v-twins only for me.

This would also be because cars are irrelevant on the street. :p

Also - Italian V-Twins: Great bikes, until they break down which is on any day with a "y" in the name. No shortage of times I've helped Ducati riders. :p
 
I may type corrected on this one, my Latin isn't the best and I don't really care enough to go look it up. :dunno:

Forum is 2nd declension neuter. So the nominative and accusative plural would be fora and foris would be used for ablative and dative. The use of the word is in the accusative plural so it's fora.
 
So, you're saying that a GTO with 365ft-lb@4000rpm is somehow less destructive to the transmission and is torquier than a 5.4L that makes 385ft-lb? :blink:

No Cobra Mustang has had a 5.4L. *shrug*

Assuming it didn't already wipe those out. :p

Again I've never had the problem personally and neither have my friends/acquaintances.

Let me put it to you this way. One of my clients is an actual Government Motors dealer, and their service manager told me about how they'd had to replace lots of T56s under warranty.

I refer to my Camaro drivers comment earlier. :p Plus the synchro issue is solved with improved clutch hydraulics. It's even less of a problem with an aftermarket clutch.

This would also be because cars are irrelevant on the street. :p

Also - Italian V-Twins: Great bikes, until they break down which is on any day with a "y" in the name. No shortage of times I've helped Ducati riders. :p

I disagree. :p

That's Ducatis. Aprilias are quite a bit more reliable.
 
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Failing transmissions or not, I'd still have the V6 RS with manual.
 
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