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Overdrive lockout

9.3K views 4 replies 2 participants last post by  LadyLiberty24  
#1 ·
So Ive read around and cant find anything about this but seems like it may be a fairly smart idea but the lack of threads on it leads me to believe there is a terrible flaw in this plan that I am missing. Everything ive read about running extra hp through a stock trans seems to say that the shift and down shift that is where a typical limp code is thrown is the shift into overdrive (4-5 or 5-6 on newer models). If that is so than whenever your planning on going WOT wouldn't locking out overdrive until you were up to speed ( like getting onto a freeway or something) and once you got back to cruise speed unlock it and continue with your drive to hopefully eliminate the tranny slip? Also will Tow/ haul mode really help when you plan on dicking around and racing someone every once a while to throw it into tow/haul mode should help prevent slips because it locks the torque converter and if you only use t/h mode for racing then the tranny will already know once you turn on t/h that your about to beat her up a bit? thats what ive concluded from my readings on this site but i would just like a decisive answer and to know if locking out overdrive is a bad idea. thanks!
 
#2 ·
I do it when I use the big tunes..... Just don't push the trans hard on those because it'll kill it even quicker. As far as tow/haul, I used to switch in and out of that when changing tunes but the truck still shifted like crap. Plus, when I needed tow/haul for actually hauling, the trans really hated me then.

As far as converter locking, when you go wide open with t/h OFF, the converter locks 2-5 anyway, so it's basically the same as t/h ON. I leave t/h for hauling, just run my tunes with it off and let the trans learn.
 
#3 ·
thanks! i thought itd be pretty common thing for people to do if that shift kills but ive searched many times and couldn't really find a thread on it and was wondering if there was some fatal flaw in my idea haha will fourth start red lining and need overdrive at a certain speed?
 
#4 ·
Stock tunes yes. But OD can handle the power as long as you're not raping on it. It's the lugging the motor down in 5th or going wide open on the 4-5 shift that causes the trans to limp. Just cruising isn't a problem. I went on a 800 mile road trip with a 500hp tune in and a stock trans. Never limped. Just gotta be careful how you drive it.