T-56 six speed

02 2500 Avalanche · December 4, 2002

Hey guys. I currently am in the process of buildind a 454 for my 1961 apache 10 stepside. My question is will a t-56 tranny stand up to the torque of this engine? and are there any special things needed to adapt the six speed to the block? My curent plan includes getting a lakewood bellhousing for 58-80 chevy v8, a Hays aluminum 168 tooth flywheel with an 11 inch centerforce dual friction clutch. I just wanted to make sure these parts will work together before I order them. Thanks

Alex

02 2500 Avalanche · December 6, 2002

Any one have any insight on this?

CMNTMXR81 · December 6, 2002

If memory serves me correct, the T-56 is rated at 450lbs-ft of input shaft torque. How realible that number is, is simply a guesstimation.

The T-56 used in the F-body is virtually the same T-56 used in the V-10 Viper. The shifter mount is in a different location and I think they do some updrages to the synchro's but otherwise they are the same. So if it handles the Viper's torque and so far mine has lasted, I don't forsee a problem.

I will warn you though that the synchro's in them are kinda cheap. It probably wouldn't hurt having a transmission shop that has experience with these transmissions (as you can't just split it apart and work on it like an old 4 speed) go through, replace and beef up whatever is needed.

To give you an idea of how complicated these transmissions are, unless the GM dealer has a certified technician in repairing these, they simply warranty replace the whole trans as it's cheaper to replace them than to work on and repair them.

02 2500 Avalanche · December 6, 2002

Thanks CM. The tranny I am planning on buying is out of a 1995 corvette. I am going to look into having it built up to handle my engine (it should have around 650hp and 600tq). The only thing Im worried about is if it will bolt up to the lakewood bellhousing. I also do not know whether or not it will be worth it to spend the extra money for a aluminum flywheel as apposed to a steel one, I know that aluminum dissapates heat better and its lighter. This truck is being built to drag race and I am not cutting any corners.

Alex

CMNTMXR81 · December 9, 2002

I would definetely look at one from a later Vette or F-body. The early T-56's (like 93, 94 and possibly 95) weren't as strong as the 96 and 97 LT1 as well as the 98+ LS1 versions if you don't want to beef it up at first.

Either way, if you build it, it will be irrelevant.

MarkD · December 9, 2002

I think the Viper version has a stronger input shaft. A friend of mine had his rebuilt several years ago and had a shop go through it. I can try to get contact info if you are interested. They do a lot of development work for f-bodies.

02 2500 Avalanche · December 9, 2002

Well the guy wants $1300 for the tranny, but I am seeing al kinds of T-56's on ebay that are 2000's and 2001's for $1200. Im going to look for a newer one like you said. I think I am still going to have it sent out and beefed up because I don't want to take the tranny out all the time because of the way I drive this thing.

Alex

CMNTMXR81 · December 10, 2002

Have you looked on LS1.com and LS1tech.com in the classifieds? I know I've seen them there and in some cases cheaper. They may be grenaded units (most likely synchro's), but if you're gonna take it apart, that may not be an issue.

I'm not sure of the Viper version may also have more splines in it's input shaft as well as being a beefier unit.

02 2500 Avalanche · December 10, 2002

Ya I have looked on ls1.com and I will head over to ls1tech and check it out.

Alex

t-76y2kss · March 18, 2003

In my opinion a t-56 is a poor choice for drag racing with 600hp BB. I have trashed 4 of them in my 600hp 2000 camaro ss.If you drive it easy it would last,but 6000rpm clutch dumps at the tree throttle on shifts your living on borrowed time. Synchros and shift forks are their weak points.Viper t-56 would be better choice,built th400 with right convertor would net quicker e.t,s.

02 2500 Avalanche · March 18, 2003

Ya I was looking at the viper T56 and mabey even the richmond 6 speed or mabey even their 5 speed tranny, anyone have any feed back on the richmonds?

Alex

Import Hater · March 19, 2003

The tranny I am planning on buying is out of a 1995 corvette.

Don't know if I'm too late to add my input on this...

But, first off...if the tranny is coming from an '95 Corvette, it is NOT a Borg Warner/Tremec T-56. The '89-'96 Corvette had the ZF made 6-speed. A better, although more expensive, unit in my book. The T-56 shift feel requires more "precision" I suppose than the ZF. The ZF had a heavier effort, but it felt more solid through the gates. That's the only way I can describe it. Anyone who has driven an early '90's Corvette and then a new C5 would agree. That said, the T-56, especially in the one out of the Z06 can handle some serious torque. And it can be built up to handle even more.

I've heard mixed results with the Richmond trannies. So I'd stay with the course you were already on.

Rob

silverado3500 · March 21, 2003

Don't know if I'm too late to add my input on this...

But, first off...if the tranny is coming from an '95 Corvette, it is NOT a Borg Warner/Tremec T-56. The '89-'96 Corvette had the ZF made 6-speed. A better, although more expensive, unit in my book. The T-56 shift feel requires more "precision" I suppose than the ZF. The ZF had a heavier effort, but it felt more solid through the gates. That's the only way I can describe it. Anyone who has driven an early '90's Corvette and then a new C5 would agree. That said, the T-56, especially in the one out of the Z06 can handle some serious torque. And it can be built up to handle even more.

I've heard mixed results with the Richmond trannies. So I'd stay with the course you were already on.

Rob

I was about to bring up the same point about the ZF-6!

Great minds think alike