Are all 6cyl t5's the same?

[XFGHIA747 76]

Hey guys are are all the t5s the same strength wise from ea to au ? Or are the tremec boxes better? Looking for a t5 to go on my au bellhousing i have whats my best options or doesn't it matter ? Can get a 89da t5 and one from a ef ?

 

Also a au manual flywheel will bolt up to a bf crank im presuming? Cheers

[SirkWhyXF 1,533]

I'll be interested to see the responses to this one.

 

To my knowledge, or from what I have been told, they are all the same strength wise, it's just ratios and input shaft lengths that differ?

[Menice 331]

t5z i hear might be stronger, mostly the ratio's are just different between them

[gerg 10,871]

As a general rule, the taller the 1st gear, the higher the torque capacity.

 

EA-EB1 1st is 3.50

 

EB2-EL is 3.25.

 

T5Z was found in V8's and XR6Ts, has uprated bearings and 2.95 1st. These have a longer input shaft by 5/8". They also have a relocated shifter housing. They are a direct lift from the Mustang. I think AU- onwards used this kind of arrangement on both 6s and 8s but the 6s didn't get the T5Z gearset.

 

BA had 3.35 1st, not sure of AU but could have been same.

[broken-wheel 659]

they all break going into 3rd with 275's on the back, probably the reason ford used skinny tires on the XR6T, i have broken about 3-4 of them one going into 2nd and the rest going into 3rd, the single rail 4 speed is much stronger but no overdrive

[SirkWhyXF 1,533]

That doesn't sound promising, i will be running 275's with a t5 in my xf. Oh well just have to see how we go, might have to start collecting spare t5's

[broken-wheel 659]

there is a theory floating around that if you keep the tranny cool it will last longer, something to do with different rate of expansion of alloy vs steel in the bearing and it opens up a little too much when the oil gets hot but to me that never happened, got out of the drive way drove sensibly for 2km to warm up the motor and stopped on it, rev limiter change to 3rd and bang! that was an ED XR6 box, then got a EF XR6 box and same thing happened, then I had an EF XR6 and with bigger tires same thing happened. Will never use a T5 again in anything with 200rwkw and 275's

[SirkWhyXF 1,533]

Well wont have 200rwkw, maybe a little more than 200 i think but at the fly. So may last a while, will see...

[gerg 10,871]

Horsepower doesn't break gearboxes, torque does.

[wagoon 2,429]

Mechanical sympothy will get you along way as well, so long as your aware of any issuse you can make allowances for it and it will be fine. That goes for any part on a car

[SirkWhyXF 1,533]

Of course, but sometimes it's hard to be sympathetic...

[wagoon 2,429]

I know what you mean which is why I wouldnt go 5 speed, but it will last so long as the torque shock isnt to much through the drive line. Its better for the tyres to break traction then there isnt as much torque shock, pretty good reason for burnouts everywhere I think :-)

[broken-wheel 659]

you need a fuse ....so the T5 is the fuse in most cases

[gerg 10,871]

T5s have a steep helical cut into the gear teeth to make them quieter but this increases end thrust, putting a lot of stress on the thrust races and radially on gears and shafts too.

 

There are gearsets available that are made with less or no helical and can reportedly handle 500ft-lb but are expensive and the straight-cut ones are noisy. Imagine a reverse gear whine in every gear.

[broken-wheel 659]

yeah I got quoted like 5k for a set form PPG for straight cut, http://www.ppgearbox.com.au/page.asp?productid=30

not worth it! cheaper to buy a Jerico 4 speed (top loader pattern) which will look at 1000hp and say "is that all you got boy?"

[gerg 10,871]

Or 3 grand will get you a TKO and you'll never look back

[78xcgxl 241]

The T5 behind my AU engine took a lot of abuse with no issues and 265 tyres and plenty of clutch dumps. Will see how it handles the more potent Barra. Seen plenty of T5s in 200- 300rwkw cars with no issues. I guess it really comes down to how you drive it and keeping in mind most just install a good second gearbox that already has wear and tear. 

 

The most common issue is the 3rd gear break which go figure is pretty much most of the time caused by a 2nd to 3rd miss shift. A short shifter is said to likely reduce the likely hood of this happening.

 

In regrades to the strongest T5 would definitely be T5s in BA/BFs they have a far greater spline count on the input shaft, compared to XF to AU T5s.

[wagoon 2,429]

T5s have a steep helical cut into the gear teeth to make them quieter but this increases end thrust, putting a lot of stress on the thrust races and radially on gears and shafts too.

 

There are gearsets available that are made with less or no helical and can reportedly handle 500ft-lb but are expensive and the straight-cut ones are noisy. Imagine a reverse gear whine in every gear.

And there's the technical answer to instead of take it easy and it won't break.