Superformance coupe gearbox

[flea65]

I have a Superformance daytona coupe with a tremec T3550
5-speed gearbox.
I am having troubles with the gearbox (rattle in fifth gear) and want to
replace the gearbox with a brand new Tremec T56 6-speed gearbox.

When i swap the gearbox i also want to replace the clutch, flywheel and
need a different Bellhousing ?
What are the best options for clutch, flywheel and bellhousing ?

Further information:
Engine: Ford Roush 427-781

Best regards
Flea

[Jim Vander Wal]

The T56 Magnum will fit. I'd go with the .6x whatever 6th gear OD not the .5. I think the coupes have the Dana differential with 3.46 gears.
You'll need the appropriate bellhousing, An aluminum Ford or QuickTime steel would work, talk to your provider.
I like the McLeod RST or heavier duty RXT.
You'll need a shorter driveshaft.
Pull the engine. I've been party to doing the swap with the engine in place. Never again.
The shifter may be in a different location.
Jim

[rcweingart]

I wouldn't want to pull the engine if you don't have to. Why go through all the bother of pulling the hood, breaking the a/c lines. draining the coolant, etc.? If your car doesn't already have a removable tranny cross member, cut the old one out and install Pete Brock's BRE removable tranny cross member. The 6 speed takes a different adapter to mate to the cross member than the 5 speed as well as a shorter drive shaft. If you want to minimize all of that hassle, replace the T56 with a TKO 600 5 speed. It's stronger, quieter and smother.

[eschaider]

Tremec only makes the Magnum variation of the T-56 today. The transmission is Tremec rated at 700 ft/lbs of TQ. The Tremec TKO600 is Tremec rated at 600 ft/lbs of TQ.

TKO transmissions are well known for having a very poor shifting experience when going quickly from second to third gear. The problem is rooted in a poorly designed timing interlock mechanism going from second to third. Liberty manufactures replacement parts to fix this problem.

T-56 transmissions have double and triple cone synchronizers as standard equipment. TKO's have old style brass synchronizer rings that are overloaded doing their job. Liberty and others offer an aftermarket carbon fiber faced synchronizer replacement.

When you get done with all the corrective "fixes" for the design shortcomings Tremec never choose to address, your TKO will cost as much as or more than a T-56 and not provide any where near as good a driving experience. If you want the shifter forward of the normal T-56 location Tremec has a mid shift location available on T-56's.


Ed

[rcweingart]

Never had any problems with my TKO600 and Pete Brock used it for the R&T track tests where it was put through its paces. Shifts smooth and fast, no chatter, quiet. In any event, whatever tranny you use, don't pull the engine unless you absolutely have to. Way too much involved for a simply clutch or tranny change unless you have the old welded in tranny cross-member and, if so, cut it out and replace with the BRE removable cross-member so you can change the clutch or tranny without pulling the engine.

[ItalGerBrit]

Originally Posted by flea65

I have a Superformance daytona coupe with a tremec T3550
5-speed gearbox.
I am having troubles with the gearbox (rattle in fifth gear) and want to
replace the gearbox with a brand new Tremec T56 6-speed gearbox.

When i swap the gearbox i also want to replace the clutch, flywheel and
need a different Bellhousing ?
What are the best options for clutch, flywheel and bellhousing ?

Further information:
Engine: Ford Roush 427-781

Best regards
Flea

I just finished my new Coupe(CSX9000) and bought the Tremec T56/clutch/bellhousing that Superformance/Hillbank recommends for coupes. The scattershield is a Lakewood Quicktime. Clutch, McLeod. Call Hillbank and they can tell you what to get. The trans crossmember on the new coupes is removable so you might want to get that as well. Like you, I hope to never have to pull engine/trans and install it again. Super tight fit and a PIA! The entire engine/trans installation was a PIA because of all the fittings, hoses, brackets etc, not included with the car. You will have to make your own slave cylinder bracket to fit that bellhousing as well. Hope this info helps you.
Phil

[flea65]

Thank you all for your answers, there is a lot of expertise on this forum.

Back to my problem, I have a rattle in 5th gear of the Tremec t3550, the other gears
are working without problems. What could be the cause of this problem ?
The gearbox is already disassembled and revised 2 times but he problem remains.
Does anyone have the solution to the problem ?

[ItalGerBrit]

Originally Posted by ItalGerBrit

I just finished my new Coupe(CSX9000) and bought the Tremec T56/clutch/bellhousing that Superformance/Hillbank recommends for coupes. The scattershield is a Lakewood Quicktime. Clutch, McLeod. Call Hillbank and they can tell you what to get. The trans crossmember on the new coupes is removable so you might want to get that as well. Like you, I hope to never have to pull engine/trans and install it again. Super tight fit and a PIA! The entire engine/trans installation was a PIA because of all the fittings, hoses, brackets etc, not included with the car. You will have to make your own slave cylinder bracket to fit that bellhousing as well. Hope this info helps you.
Phil

Correction. Hillbank ordered the trans for me but Mcleod clutch and bellhousing came from Roush. I have a Roush 427SR engine.

[rcweingart]

Please be more specific. Can you be more specific when you write "rattle?" Is it something you hear, something you feel, etc.? Likewise, specifically where is it coming from if you know? Shifter, tranny itself, etc.? Does it affect the way the car itself drives? Is the car lurching, bucking, hick-uping or anything like that?

[flea65]

Thank you for your reply.
It’s something i hear, i do not feel anyting.
If i switch to 5th gear and release the clutch, the rattle starts. As soon as i press
the clutch, the rattle stops.
The car drives fine, no strange vibrations, even if i hold the gearshiftknob, there is
nothing to feel, no vibrations.
It think the sound is coming from the front of the gearbox.
It only rattles in 5th gear, all other gears no rattle’s.

[rcweingart]

Obviously it is hard to diagnose without seeing/driving the car. Apparently there is no adverse functionality, no vibration that you feel, no drivability issues, more of an annoying sound that you want to locate and address. You've had the tranny disassembled twice without finding anything wrong and I presume the shifter as well. I suggest removing the tranny console top cover so that the tranny and all are exposed. Have someone in the car with a mechanics stethoscope, a rubber tube or some other other device to use to try to locate where the sound is coming from while the car is being driven and go from there.

[maurice19]

Sometimes a throw out bearing going bad will make that sound

Maurice

[rcweingart]

Yes, that or the linkage except this rattle is only in 5th gear and you'd expect the rattle in all 5 gears if it was the TO bearing or linkage which is why I'd pull the tunnel cover so someone could try to determine exactly where the rattle is coming from so they could then address it.

[1795]

What RPM are you shifting into 5th gear at, and what RPM does it drop to after shifting? Does the sound go away at higher RPM's in 5th gear?

My father had a small chevy truck with a 4 banger and he used to shift that thing into 5th gear at about 35 mph to save gas. It would rattle and make all sorts of noise because 5th gear was not made to handle that low of speed. The transmission lasted about 25,000 miles.

Not saying that you are shifting that low, but you might be shifting just a little too low for your differential ratio. if there is no rattle at higher RPM's n 5th, that might explain the rattle.

If not, then I am thinking that it might be the linkage rubbing on something as there is not a lot of room in the tunnel and so far nothing has shown up on internal examination of the transmission.

[flea65]

i am shifting from 4th to 5th at 80mph,
the rpm drops from 3100 to 2400.

I speeded up to 120MPH but the rattlesound does not go away, unfortunately.

[Blacklemming]

Originally Posted by flea65

i am shifting from 4th to 5th at 80mph,
the rpm drops from 3100 to 2400.

I speeded up to 120MPH but the rattlesound does not go away, unfortunately.

Buy open exhaust pipes,the sound wil be gone

[Turbonut48]

I agree with the open or loud pipes.
Huh? What? Eh?

The Nut

[Texasdoc]

You can also try a Steelman Chassis ear (wired or wireless) to help narrow down the source if you don't have a friend to work the mechanical stethoscope while you drive.

[eschaider]

Originally Posted by flea65

... When I swap the gearbox I also want to replace the clutch, flywheel and need a different Bellhousing ?...

As long as you are replacing the transmission why are you spending time and potentially money for a problem that will either be sitting on the floor in your garage or parted out?


Ed

[Turbonut48]

Get in touch with olddog, he s taking out a t3550.

The Nut