I have had 3 TKOs in my SPF replica and logged over 50,000 miles on them. Road racing, drag racing and spirited street driving. The last 40,000+ miles have been behind a very stout running Roush 427R. I have yet to trash a gear. With all do respect, I think the 3rd gear failure fear is BS. I do think that the TKO 600 is very difficult to shift quickly and reliably at high rpm. Brent has mentioned mods that will help this. I am sure there are numerous folks that can do these mods. I can say for sure that these people do good work and that their upgrade makes the TKO 600 shift much smoother and very reliably at 6200+ rpm.
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