Why is the mr tranny weaker than all the others? Which tranny is the best? Would it be better to put a 5 speed tranny into the mr to make it better? What are the advantages and disadvantages of the mr to the others and the others to the mr

 

from what I've read - the transmissions are the same size, so the gears are smaller on the 6 speed so they can stuff one more in there, thus making them weaker in general...

and yes, you can put a 5 speed in an MR... most people do. I don't know what's required for the swap but I know companies like Shep, TRE, Jack's, Buschur probably sell the kits

 

If you are racing I would say get a 5-spd, but I know a lot of guys that have the 6 and they are happy with it.

 

I just didn't want anything more to do with Euro crap in my cars. I've had too many issues in the past. No Sportronic for me. I'm sticking with Japanese. LOL

 

So since I'm not going to be racing just stick with the 6 speed?

 

You can rebuild the 6 speed to hold a little more power.

 

How much are rebuilds unusually?

 

5 spds is stronger than a 6 spds.

From shops like ER, shep, jack and boosting, i think tranny rebuild starts from 800 and can cost very expensive. None of shops can tell you untill they open your tranny. But this price included a lot of things, like replacing all seals, bearings, and syncros.

For swap to 5 speeds, you need to get few stuff like shifter base, bushing cable etc etc. All that is about 500 new and you can get them used for cheaper.

Edit: There are many good info out there about transmission and rebuild costs. Search thru "engine/drivetrain" section.

 

It is really up to how you drive. If you are not bang the gears all the time, i can say 6 spds is good for street/daily uses.

 

From what I've read the longevity of the 6 speed box is very dependent on the output of the engine, especially torque. Keeping your power below 500hp and 400 ft/lbs of torque and driving the car with some mechanical sympathy should help keep things together. Also having a maintenance routine that includes frequent oil changes for the tranny, transfer case and rear diff will help. I would also think that clutch choice would make a difference to transmission life, not sure what type would be best though, maybe one rated at less than 450ft/lbs or so.

 

Road racing is what kills the 6 speed. There are plenty of people making a lot of power/torque with the 6 speed for street cars. What happens is 4th gear is what typically goes out because of the excess heat created from extended use in that gear, which is between 75-115mph. You are not going to have problems with it on a street car.

 

I'd like to thank everyone who contributed, all of Thai info is very helpful and I can say im very grateful at the least