Just bought a Yank PT4000 for the 99 HOSS in my sig. Not sure what to expect. I'm currently running a very old Yank ST3500 that feels like a 4500+. I suspect it may have an internal problem. It has about a 1000 rpm shift extension. The 60' in the sig was cut with bias ply 26" ET Streets. Data logs show rpms rise to 5000 rpm by 6 mph launching and 1-2 shifting at 6450 the rpms fall back to 5450 and 2-3 shifting at 6650 the rpms fall back to 5650. I suspect the PT4000 to feel even looser but hope it is more efficient on the top end. Any thoughts?

 

I dont think it will feel looser, sounds like that one you got now is pretty out there. Performance all around should improve.