# 05 GTO (6spd) weakpoints...



## AWD (Apr 21, 2008)

Please list'em 

I want to know what I need to beef up first before I start doing things up front


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## Rukee (Feb 8, 2007)

Welcome to the forums.


Just need to watch the loose nut behind the wheel. :willy:


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## AWD (Apr 21, 2008)

Rukee said:


> Welcome to the forums.
> 
> 
> Just need to watch the loose nut behind the wheel. :willy:


haw haw haw

lol


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## fergyflyer (Apr 18, 2005)

Depends on your goal. 

If you leave the car stock or just do bolt ons it's pretty stout. The clutch, and the tranny synchros are the only thing that might give you issues. 

As with any car as you add power things become more marginal. One of the Mods here found out this weekend that when you're at the 600 hp mark it builds speed real quick, but it needs the brakes upgraded.


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## AWD (Apr 21, 2008)

Well thats a given! lol

How well does the driveshaft hold up? I've seen some pics of it compared to some aftermarket ones and well....it has my attention!


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## AWD (Apr 21, 2008)

Dang, 97 views and only 2 replies! 

booo..


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## GTO JUDGE (May 14, 2005)

There has been a lot of discussion on this topic in the past. Use the search function and explore the archives, you will find a boat load of answers to your question. :cheers


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## 2006GTOLS2 (Sep 23, 2005)

There are no weak points in the T-56 tranny. It is very stout, good for up to about 500HP, and was used in vehicles such as the Viper and Cobra, as well as the GTO. The only shortcoming is an idiot driver that either breaks the shifter in two, or damages the synchros somewhere along the line. Hopefully, this will not be you. Good Luck.


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## Tri-Power (Jan 10, 2008)

AWD said:


> Well thats a given! lol
> 
> How well does the driveshaft hold up? I've seen some pics of it compared to some aftermarket ones and well....it has my attention!


One of my good friends has a procharged one that puts a bit over 700hp to the ground, and he made the mistake of neglecting his driveshaft, well one night at the track, on a good launch (with street radials) he got a visitor through his floorboard. It held up good for a couple months on the street, but when faced with the extra traction of the track, it just let loose, and he has regretted it for a while now. But keep in mind, that is WAY more power than you will achieve with bolt ons.


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## fergyflyer (Apr 18, 2005)

2006GTOLS2 said:


> There are no weak points in the T-56 tranny. It is very stout, good for up to about 500HP, and was used in vehicles such as the Viper and Cobra, as well as the GTO. The only shortcoming is an idiot driver that either breaks the shifter in two, or damages the synchros somewhere along the line. Hopefully, this will not be you. Good Luck.


I can tell you at least a half dozen people that have had issues with their T-56. 

The feel is aweful unless you change the shifter on a stock GM car. 

A member here that put mostly highway miles on his car had the synchros go at around 50,000 miles, Groucho. 

Just about everyone I know that races has issues with synchros and the clutch. 

Maybe if you drive the car on the street and never race it, it might be fine.


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## 2006GTOLS2 (Sep 23, 2005)

fergyflyer said:


> I can tell you at least a half dozen people that have had issues with their T-56.
> 
> The feel is aweful unless you change the shifter on a stock GM car.
> 
> ...


True, the throws of the stock shifter on the GTO could be better. But, to address your point.....if you race a vehicle on a regular basis, you can expect to have trouble at some time or another. Constant abuse will eventually leave you stranded, in some form or fashion. If you treat your car right, it will treat you right.


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## koman (Sep 25, 2006)

really it depends on your goals and expectations out of the car. if you want to drag, then upgrade the half shafts and driveshaft and add a loop for safety along with change your suspension some. if you want to road race, take full advantage of the irs and set the suspension accordingly while upgrading the driveshaft maybe. remember there are not many performance related rear gears for these cars. 3.73, 3.91 and that's about it outside of stock 3.46. clutch is something you might have issues with if you slip it often as if you are driving a low low end torque 4 cylinder but if you drive it like what it is then clutch shouldn't be much problem unless you are dragging it. as fergy said about the brakes upgrade to better rotors and pad material at least and you'll have a pretty decent braking system. after a few months and experiences with the rotors i have i'd still like to have a slight bit more for top end slowdowns but it feels way better than the originals which i'm still conditioned for  good luck and enjoy your ride! set goals before you buy parts...


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## fergyflyer (Apr 18, 2005)

2006GTOLS2 said:


> True, the throws of the stock shifter on the GTO could be better. But, to address your point.....if you race a vehicle on a regular basis, you can expect to have trouble at some time or another. Constant abuse will eventually leave you stranded, in some form or fashion. If you treat your car right, it will treat you right.


I can see your point. Most people buy a performance car to run it every once in a while and a decent portion buy it to drive it hard. Kinda like buying a truck, most people buy it to haul something, so you build it so it can do that. 

I had a friend that had his transmission break on him. He was at the 400 rwhp point and he did/does race it a bit. He got it rebuilt, and it cost about 2000 to get it done along with a heavy duty Spec clutch. We knew the guy that was rebuilding it and he showed us the parts that he replaced. They were rather flimsy compared to what was put back in. If Tremec had put the better parts in in the first place, it might have added $100 to the price of the T-56. I say might, because that's how much extra the parts cost gettig them through wholesale sources, Tremec could get them direct for less. Not only will the transmission handle up to 700 rwhp, it will handle it at the strip. The shift feel improved a bit too. 

The Tremec was a big factor in my buying an A6 in my C6, instead of the M6.


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## patisi (Oct 23, 2004)

fergyflyer said:


> I can see your point. Most people buy a performance car to run it every once in a while and a decent portion buy it to drive it hard. Kinda like buying a truck, most people buy it to haul something, so you build it so it can do that.
> 
> I had a friend that had his transmission break on him. He was at the 400 rwhp point and he did/does race it a bit. He got it rebuilt, and it cost about 2000 to get it done along with a heavy duty Spec clutch. We knew the guy that was rebuilding it and he showed us the parts that he replaced. They were rather flimsy compared to what was put back in. If Tremec had put the better parts in in the first place, it might have added $100 to the price of the T-56. I say might, because that's how much extra the parts cost gettig them through wholesale sources, Tremec could get them direct for less. Not only will the transmission handle up to 700 rwhp, it will handle it at the strip. The shift feel improved a bit too.
> 
> The Tremec was a big factor in my buying an A6 in my C6, instead of the M6.


Hmm... FergFlyer I never knew that was a reason for you got Auto on your C6. So far, I have been lucky with my '05 M6 at 31K she shows no signs of slowing in terms of the T56, I also have the same in my '04 Snake, at 35K, and she seems to be fine there too. I have also gotten used to the long throw shift in the Goat and the boxy, stiffer feel on the clutch in the Snake.The same solution works for me in both cars. I usually let off the clutch pedal quick, I never, ever ride it. So from the time the cars begin to roll say 1 - 3ft, I am off the clutch. This also gives me instant power to the rear wheels and forces the IRS to do its job. 

Now of course if I punch it at that time I am likely to get a little wheel spin on take off especially if I am at a stop where I have to make a turn. You can here the LSD catch and release as it transfers power to the inner or outer reas depending on which turn you are making.


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## GTO JUDGE (May 14, 2005)

99% of the vehicles I have ever owned were stick, In fact I only get automatic so the wife can drive those particular cars/trucks. Every manual trans I had the stick always had (some sloppy) loose, long throws. This GTO is the first vehicle I ever had where the shifting was tight, short, and when shifting into gear it feels like a 2 step process. It took me a while to get acclimated to it. I am sure a rip shifter is the "bomb" and I would love it, but I don't mind my shifter at all.

Now if I were taking it to the track I'd dump the shifter and replace it. The shifter will inhibit your performance at the track. I can see why guys are replacing it, but for me and my application, it's ok for me.


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## Gotagoat (Jan 6, 2006)

GTO JUDGE said:


> 99% of the vehicles I have ever owned were stick, In fact I only get automatic so the wife can drive those particular cars/trucks. Every manual trans I had the stick always had (some sloppy) loose, long throws. This GTO is the first vehicle I ever had where the shifting was tight, short, and when shifting into gear it feels like a 2 step process. It took me a while to get acclimated to it. I am sure a rip shifter is the "bomb" and I would love it, but I don't mind my shifter at all.
> 
> Now if I were taking it to the track I'd dump the shifter and replace it. The shifter will inhibit your performance at the track. I can see why guys are replacing it, but for me and my application, it's ok for me.


This has been my experience too. I've owned a Porsche that had a much sloppier box than the GTO and four Mustang GTs that had a tighter feel. As stated by others, I think the T-56 is fine for the intended use (street driving) but if the car is to be raced in any manner, some upgrades -- especially the shifter -- are needed.


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## fergyflyer (Apr 18, 2005)

I've driven a bunch of sticks in vehicles. I had a Contour SVT that had a just about perfect gearbox to it. The C4 had a ZF transmission that was great too. The length of the throw doesn't bother me so much as the vagueness of it. I always knew what gear I hit with the C4 or the Contour SVT, and to a bit lesser of a degree the Mustangs I've had and driven. The T-56 equipped cars and a Nissan Sentra SER Spec-V are the only vehicles I've ever missed shifts in. The Nissan had a 6 speed and it had the weirdest shift pattern. It was a fan shaped with 2nd ,4th and 6th closer to each other at the bottom and 1st, 3rd and 5th were kinda like your fingers when your hand is flat and you spread your fingers apart at the top. 

On top of that I needed a clutch in the Z06 when I got rid of it with 30,000 miles on it. To be fair I was the 3rd owner and I think the car was ragged on pretty hard before I bought it. The GTO's clutch was soft at 20,000 miles too, but I had around a 100 dragstrip passes on it, and they are heavy. I've had cars, like the Contour SVT that I've raced a bunch and never had to put a clutch in. The Contour had 96,000 miles on it when I got rid of it. I put over a 100,000 miles on each of my 5.0 Mustangs and had both modified to the point that they had 260 rwhp in one and 300 in the other. Stock clutches with that kind of power, so I don't think it's me, I think it's the combination of my style and the design of the T-56 and the stock clutch not meshing.


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## Gotagoat (Jan 6, 2006)

I understand fergyflyer's point of view also. Only time will tell how my '05 M-6 will hold up. It's got 16K gently driven miles so far and no problems but I'll admit that it is an easy transmission to miss-shift. Even though I've grown accustomed to the vagueness, it is not a transmission I would make a habit of speed shifting from second to third or fifth to fourth. At least not with the stock shifter.


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