Transmission Blow'd Up on Track

Tune needs to be changed from 3.8 to 4.3; it is absolutely a necessity. Many notable tuners did not know this and it wasn't until I had a mechanic I trusted go to a Subaru shop and look at the Ford tuning tables and figure it out. It's an uncommon mod. I responded to your PM.

As expected, JST responded timely today by changing the axle ratio in the tune. As @Jabbit said it would, the fix was immediate; no more idle hang.

Alright, God willing, she's ready for the track on 5/3. Will report back with my impressions of the new transmission, and especially the 4.3.

Nevermind. Just found a bad gear oil leak. Apparently coming from the input shaft area, as it’s traced to where the transmission meets the motor. I assume the seal got goobered up during the 4.3 and/or LSD install. Whole transmission has to come down again. I also have to be concerned with fluid on the clutch. Yay, me.

The attached picture is the top of my splitter (shown after removal, ignore the rocks). It’s a lot of fluid.

FML

Man, that sucks!

And the culprit. They definitely goobered up the input shaft seal. Oil was everywhere, including the slave, pressure plate, and arguably the clutch disk.

While I’m out my time and aggravation to pull it down, it does sound like they are going to reimburse me for fluids, seal, clutch//plate, and a slave.

Customer service is not a thing of the past, hopefully they hold themselves to at least some of those reimbursements.

Didn’t even make it to turn 1, and it went into limp mode. P2610 and P061B. Apparently the ECU sensed over torque … I’m guessing from the 4.3 drive

Asking JST if they can correct. I reloaded the tune and it just did fine for a run.

Interesting, if not frustrating. How does the ECU calculate over-torque values? A rate increase beyond a certain number of rotations within a given time frame? Input from the gyroscope, accelerometer and magnetometer? Some combination of methods?

I’m unsure. JST was great and sent me a revision. Unfortunately, I wasn’t able to confirm that the matter is resolved, as multiple crashes kept me from being able to go out on the track the rest of the day.

He did have me confirm the car wasn’t over boosting, which it wasn’t. The P061B seemed to not be a big surprise to him, but the P2610 was new, and he was not 100% sure his revision would fix it. My gut says the two codes were triggered by the same “over torque” condition created by the 4.3 + big turbo. Interestingly, when the car kept going into limp mode, only the P061B code came back anyway.

I will report back after my next track day. All in all, the 4.3 gets a thumbs down so far. Was expensive, a pain to get installed, and created needs for tune revisions. And, most importantly, I don’t think it made me faster; for every corner in which I now have better pull, I found wheel spin in other corners and had to introduce new upshifts at the end of a couple straightaways.

I’m unsure. JST was great and sent me a revision. Unfortunately, I wasn’t able to confirm that the matter is resolved, as multiple crashes kept me from being able to go out on the track the rest of the day.

He did have me confirm the car wasn’t over boosting, which it wasn’t. The P061B seemed to not be a big surprise to him, but the P2610 was new, and he was not 100% sure his revision would fix it. My gut says the two codes were triggered by the 4.3 + big turbo resulting in a calculation that was greater than the tune’s commanded torque tables were set. Interestingly, when the car kept going into limp mode, only the P061B code came back anyway. It’s also interesting that this didn’t come up with spirited street driving, but twice happened IN THE FIRST STRAIGHTAWAY as I entered the track.

I will report back after my next track day.