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ClimberD@HexMods 05-08-2012 12:23 PM

5EAT Ask your Questions!?!
What do you want to know about the 5EAT and related systems?

I'm going to write a big long FAQ, with answers to whatever people want to know.
In the end this should save a lot of our collective time, since people keep asking the same questions, and we keep writing answers. Instead, people can just say, "Read the FAQ [link]".

If I do a good job, hopefully it can become a sticky.

Sample Questions:
What are clutch packs?
What trans cooler setup should I consider?
What fluid should I use?
How to do a flush?
How much power is lost through the 5EAT?

Ask away! :)

fishbone 05-08-2012 12:30 PM

If many of the internals are shared with the JATCO 5-speed units used in the Infiniti G and Nissan Z, which are rated at around 300hp stock, is it a fair assumption the reliability is comparative on the Subaru implementation up to similar numbers, or is this reduced by the difference of rwd vs awd and power delivery?
Inquiring minds want to know :lol:

planelazy 05-08-2012 12:33 PM

Get some free marketing and mention your mods :P

nimrod685 05-08-2012 12:47 PM

Where exactly is the "passthrough/access panel" in the flywheel housing that allows you to "stick a screwdriver into it" to stop the crank pulley from turning?

90G60 05-08-2012 12:54 PM

What is the safest way to launch a 5EAT?

The trick is you can't answer with "Don't launch it at all".

golunnova 05-08-2012 01:20 PM

I have a 08 LGT and have a harsh shift from 2nd to 3rd gear. Read about some members bringing it to the stealership for a TCU Reset and relearn. Any comments on the results?

fishbone 05-08-2012 04:57 PM

By the way my question was for shits and giggles because I've heard that argued before. The answer is no, there really can't be made an accurate comparison because of the difference in drivetrain and power delivery of the motor.

seabass07 05-08-2012 05:15 PM


Originally Posted by 90G60 (Post 3884892)
What is the safest way to launch a 5EAT?

The trick is you can't answer with "Don't launch it at all".

Do it without spinning any wheels.

underground000 05-08-2012 05:32 PM


Originally Posted by golunnova (Post 3884957)
I have a 08 LGT and have a harsh shift from 2nd to 3rd gear. Read about some members bringing it to the stealership for a TCU Reset and relearn. Any comments on the results?

There are 2 'options,' depending what is required from the dealer
1. There is a TSB on this harsh shift, and the update may or may not fix this problem. If it doesn't, dealer will require the car to be brought back for more inspection after putting a few miles on the car.

2. If (1) has been performed, the TCU will need to be set to 'learn' this will erase all programmed data.

I can say from experience, #1 did not work, and #2 worked. Well... #2 worked because there was a error code but no check engine light.

golunnova 05-08-2012 06:34 PM

Is the TSB you mentioned 16-72-07? How long did the whole process take for you and how much did the stealership charge?

lieutenantcolumbo 05-08-2012 06:38 PM

Not really looking for answers, but here's some faq's:

How many extra clutches can be added?
Will anybody ever crack the TCU software?
Will the '08's ever get a valve body?
When should I consider having the torque convertor upgraded?
Will an upgraded torque convertor improve my 0 - 60 mph or quarter mile times?
What are the highest documented whp levels being run and for how many miles?
Will a valve body improve my 0 - 60 mph times or quarter mile times?
How does IPT get away with charging $669 (was $769) for a $0.50 spring?
Does Sport Mode and Manual Mode increase line pressure?
What model year valve bodies can be be swapped?
When are center differential bushings necessary?
Does anybody offer an LSD for the 5EAT?
Is there a link to CD's valve body upgrade walkthrough?
How do I reset the TCU?
Is there a link for Free SSM?
Why does it rev higher in the winter until it warms up?
Any available rebuild kits?
How can I drive the car after I've blown out 5th or 4th gear?
The Cobb AP won't clear the TCU error codes, what can I do?

underground000 05-08-2012 07:05 PM


Originally Posted by golunnova (Post 3885471)
Is the TSB you mentioned 16-72-07? How long did the whole process take for you and how much did the stealership charge?

I was still under warranty and this was done like 1.5 years ago, so i dont really remember:lol:

really it doesnt take very long. pull in the car to the bay, plug in ssm, read and flash, test drive it, then you drive off

the TSB said .5 hours, so no more then 30min (when they take in your car, if they are not busy)

So let's say they charge $90/hr, half of that is $45 for the flash. IF this doesnt fix it, ask if you can bring it back later to reset the tcu learned parameters. Some are nice and say bring it back and we'll do it free of charge (since you already brought it in) some may be jerks and charge you a second time

Bring in the TSB, knowing information IMO makes them less of jerks (never had a jerk problem though :/ always had good experiences with dealers). I brought in the TSB, explained what was going on, and was super simple and fast:) no BS talk to me or fluff info added

fishbone 05-09-2012 10:29 AM


Originally Posted by seabass07 (Post 3885343)
Do it without spinning any wheels.

This. And don't be an idiot about the revs either.
The stock stall speed is around 3500rpms, which is considered high stall. Most autos out there have a lower stall speed.
If you hold the brakes and press the gas a bit, the revs will climb up and hold to around 2000-2500rpms. This is enough to get rid of the slack in the system and possibly be close to positive boost (out of vacuum). You can get a fairly good launch at this point.

If you press the gas pedal further down, boost will build and the revs will climb and hold at around 3500 and the car will start to squat pretty good and you will be struggling a bit to hold the brakes.
At this point you are running a good possibility of spinning at least one wheel when you take off and there is a chance something may break. And you WILL take off like a bat outta hell.

If at this point you STILL continue to hold onto the brakes and the gas pedal is pegged, from what others have reported the revs will climb to 4K and at this point you're running a pretty good chance shit will break, from what has been reported.

In my experience the best way to get a good launch and leave the hole out in a moderate hurry or at least good enough to overtake another car is to hold the gas and hold the revs at or under 3K not for too long.

If you are at the dragstrip, are looking for the best 60' times and the best launch and are willing to risk a grenaded center diff or other things OR you have a modded tranny that can take it, then by all means launch under boost at around 3500rpms.

Outside of this, there should be no reason for you to launch any higher than that unless you are doing testing and trying to find out at what point exactly the transmission grenades. If you do, please let us know as we would like to find this out as well :lol:

I have launched the car a few times at 3500rpms and although it was awesome, almost every time one of the wheels chirped when I let go of the brakes. Nowadays IF I have to leave from a stop in a hurry for whatever reason, I just hold the gas to get rid of the slack until the point that the car feels like it starts to squat, at around 2500rpm and that is plenty to impress the guy in the riced out Civic next at the light. When you let go you will be in boost almost right away.

ClimberD@HexMods 05-09-2012 10:39 AM

keep the questions coming :)

I will try to make answers as simple as possible.

seabass07 05-09-2012 11:09 AM


Originally Posted by lieutenantcolumbo (Post 3885484)
Will anybody ever crack the TCU software?

This one will get taken care of when someone with decent disassembly skills tackles it. Someone posted 5eat roms on the reverse engineering thread. They need to be defined, but I doubt if anyone here's up to it.

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