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S550 GT350 issues - wrench warning light

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9
5
Exp. Type
HPDE
Exp. Level
5-10 Years
55038
2017 GT350R I have had two transmission output shaft flange nut installed. The last one we used Red Loctite after two days on the track and its back. Sounds like should have replaced the tone ring and bearing.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
2017 GT350R I have had two transmission output shaft flange nut installed. The last one we used Red Loctite after two days on the track and its back. Sounds like should have replaced the tone ring and bearing.
BOSSLS562
How long did you run with the wrench light on?
 
9
5
Exp. Type
HPDE
Exp. Level
5-10 Years
55038
My light has not remained on for more than a few seconds, so yes it could be a different issue, but the more read about issue from other cars the more they all come back to the computer thinking that the car is going one speed and a sensor thinking something else.
GT350R
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
My wrench light came on the first time at highway speed. Shut down for two hours. Came back on at highway speeds. Stop and go traffic, no light.
I pulled the drive shaft, retorqued with orange loctite, reassembled. All go so far.
 
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Update here, after many months I finally found a dealership that fixed it!!! So excited, it truly feels like a new car, couldn’t be happier. In my case, in addition to doing the TSB, the Exciter Ring (aka Tone ring) was worn down badly. So once they replaced the tone ring and redid the TSB, my issues went away. Shifting feels much smoother, I’m so excited to finally have this car working properly, I was close to giving up on it after 3 other dealerships couldn’t fix it.
 
9
5
Exp. Type
HPDE
Exp. Level
5-10 Years
55038
I also have an update. I found a dealership that was qualified to work on GT350R's and they told me that there was another service bulletin that said to use a newly redesigned nut. The nut was replaced, as well as the flange, but the car still was acting up. The mechanic called me and said that he would replace the tone ring, seal and nut for just the cost of parts (no labor charge). He agreed that the tone ring should have been replaced when he first went in to replace the nut. Anyway, the car is now running great, and I will have the car back on the track at RoadAmerica in late September. I hope all goes well. If anyone else is having this problem, I suggest that you insist on having the tone ring replaced, since it's a cheap part (around $40) and seems to fix the problem.
 
I also have an update. I found a dealership that was qualified to work on GT350R's and they told me that there was another service bulletin that said to use a newly redesigned nut. The nut was replaced, as well as the flange, but the car still was acting up. The mechanic called me and said that he would replace the tone ring, seal and nut for just the cost of parts (no labor charge). He agreed that the tone ring should have been replaced when he first went in to replace the nut. Anyway, the car is now running great, and I will have the car back on the track at RoadAmerica in late September. I hope all goes well. If anyone else is having this problem, I suggest that you insist on having the tone ring replaced, since it's a cheap part (around $40) and seems to fix the problem.
Glad to hear yours has been fixed as well! Enjoy it!!!
 
1
2
Exp. Type
HPDE
Exp. Level
5-10 Years
Reading
Ah man, sorry to hear you’re having issues as well! I dropped my car at the dealership today, praying it’s a simple fix. It seems like the previous owner might’ve actually already had that TSB addressed several thousand miles ago and it came back, but waiting on dealership to confirm that for me. This dealership experience has been awful, hopefully your experience is much better. Best of luck and keep me posted. I will provide updates here once I hear back.
Glad to hear yours has been fixed as well! Enjoy it!!!
May be late on this conversation. Just experienced this last track day of this year, found the bulletin. The nut was not very tight, say 60lb. I did the locktite deal. Was pretty straight forward, dropped the driveshaft and mid shift support this allowed access to the nut. Torqued to 115lb

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