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GT350 Hesitation on track at high rpms in 5th gear?

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39
28
Exp. Type
HPDE
Exp. Level
5-10 Years
Atlanta
Hi all!

Hoping someone can help me out with a strange issue I've been having with my GT350. Last weekend at Road Atlanta from T9-T10 I noticed in 5th gear the car is hesitating at the top of the rpm band starting around 120+ mph and if I lifted for a cool down lap it happened in lower rpms but always and only in 5th gear.

I thought it was related to TSB 19-2135 but it did not happen when I was driving home on the highway.

I scanned the car today and no DTCs or codes present.
 
22
59
Exp. Type
HPDE
Exp. Level
20+ Years
North Central Illinois
As a secondary check to the output shaft tone ring nut issue, does the cruise control work? If no, then it could be that TSB-related issue. I replaced my tone ring and hardware when the transmission was out of the car, even though an in-car check showed the tone ring nut was torqued to spec (105 ft lbs). After the replacement, no issues with the hesitation and surge (which only occurred in higher gears under constant rpm - low or high) and the cruise worked (was non-op prior to the repair).
 
39
28
Exp. Type
HPDE
Exp. Level
5-10 Years
Atlanta
As a secondary check to the output shaft tone ring nut issue, does the cruise control work? If no, then it could be that TSB-related issue. I replaced my tone ring and hardware when the transmission was out of the car, even though an in-car check showed the tone ring nut was torqued to spec (105 ft lbs). After the replacement, no issues with the hesitation and surge (which only occurred in higher gears under constant rpm - low or high) and the cruise worked (was non-op prior to the repair).

I have not tried cruise control, I never use it anyways and the cars been in storage since my last event. I'll check the hardware when I fixed the TSB the first time all I did was replace the nut and added some Loctite. Would you happen to have the part number for the items you replaced?
 

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