6 Speed Trans Upgrade

[KrasH]

I remember reading in a thread about 6 months ago about replacement internals for the T5 that were rated way higher than what we have in the T's. If I recall it was a UK website and the parts cost were in the area of 1500 british pounds.. Would this be a more cost effective exercise?

[Guest Big Mick]

  bloan said:

Why is it that nearly eveyone is hellbent on replacing the T5 with a six speed? If the T5 is that bad and needs replacing why just replace it with a stronger 5 speed?

IMHO a sixth gear is a complete waste of time and money unless of course you live in the NT!

I agree regarding the 6th gear, however the Tremec 5 speeds all have various physical fitment issues in the T.

The T56 also has higher torque ratings available as they have been developed for cars such as the Mustang Cobra R, Dodge Viper etc.

Also, when selecting the ratios you also need to take into account the overdrive ratios in relationship to the orignial T5 if your interested in the cruise control working as if the difference is out by approx. 10% or more the PCM will think the clutch is slipping and not allow cruise. I would doubt if cruise would function in 6th gear on the T56 box with the ratios mentioned by bcl. Though I admit this is a minor point if you need a box to handle the torque.

I was quoted about $8.5K for a drive in, drive out T56 conversion on a T. This included new clutch and pressure plates, billet short shifter and all the other parts of the kit to make it complete. You may be able to get some dollars back by trading in the old box, how much would depend on the condition of the box. I don't think bcl would get much for his!

[Merlin]

  bloan said:

Why is it that nearly eveyone is hellbent on replacing the T5 with a six speed? If the T5 is that bad and needs replacing why just replace it with a stronger 5 speed?

IMHO a sixth gear is a complete waste of time and money unless of course you live in the NT!

Just because it has six speeds dosnt mean it will automatically have a higher top speed. If you get the gearing right a six speed box means the ratios can be a lot closer together, resulting in quicker acceleration than a 5 speed box. Of course you could gear it for top speed, but personally I would prefer the six speeds to be optimised between 0-140km/h.

[aps]

  bloan said:

Why is it that nearly eveyone is hellbent on replacing the T5 with a six speed? If the T5 is that bad and needs replacing why just replace it with a stronger 5 speed?

IMHO a sixth gear is a complete waste of time and money unless of course you live in the NT!

Bloan, I dont think we are all hell bent on a 6 speed trans upgrade though 6 well spaced ratios would be nice. What we are all considering is a transmission that can cope with much greater engine torque and the T56 can cope with quite high torque.

The only problem with the T56 is that the shift quality is similar to a J3 bedford truck, its not that flash. I agree a strong 5 speed trans with the right ratios at a reasonable price would be a good option for the xr6t. This entire issue needs much more investagation before making any decision on which way to proceed.

PETER

APS

[ktford]

Lachlan (LOK11) has had a 6 speed in his car since almost new & I'm still adamant that another ratio for either man/auto would be excellent even from as low as 120kph on freeways when cruising as when over 120 kph the motor starts to rev harder than I'd prefer.

Scotty

[WBT56]

  aps said:

..The only problem with the T56 is that the shift quality is similar to a J3 bedford truck, its not that flash.

PETER

APS

This would be based on? (If you say a commodore, I will herein refer to APS upgrades in the same breath as powerchip, lol.)

Edited 25/01/04 03:20 AM by WBT56

[aps]

  ktford said:

Lachlan (LOK11) has had a 6 speed in his car since almost new & I'm still adamant that another ratio for either man/auto would be excellent even from as low as 120kph on freeways when cruising as when over 120 kph the motor starts to rev harder than I'd prefer.

Scotty

The point is to have the correct ratio in 6th gear, as 6th in the Expensive Daewoo is totally pointless for street use. What is most important is to have a manual trans either 5 or 6 speed that can reliabley transfer high levels of torque and give trouble free operation for many thousands of kms at an affordable price. I know there are a number of ratios to suit the T56 trans though that's not to say the T56 is the only good option for the xr6t trans upgrade.

Peter

APS

[CnC]

APS: it would be advisable to include a computer update to sort out any possible cruise control issues as this will be a sticking point for some buyers.

[aps]

  WBT56 said:

  aps said:

..The only problem with the T56 is that the shift quality is similar to a J3 bedford truck, its not that flash.

PETER

APS

This would be based on? (If you say a commodore, I will herein refer to APS upgrades in the same breath as powerchip, lol.)

Why so sensitive on this issue ? I have driven many a car with the T56 trans and the shift quality is at best ordinary, that's not to say that the trans is not strong. I have also owned, and driven many cars with an excellent 6 speed trans so maybe I am in a better position to compare what is good or not so good. In any event the T56 would still be considered a worthwhile and affordable trans upgrade for the xr6t.

PETER

APS

[CnC]

I would love to know what alternative transmissions you are looking at