When making passes on the quarter-mile, should the transmission overdrive be left on or off? I ask because I went to the track here and left it on and now my transmission makes a quirky jump in rpm right before it goes into overdrive when I am driving at low RPMs. It isn't real bad...just annoying....and not sure why it is doing it or what it is exactly. Thanks in advance

 

Tranny can't shift into overdrive in the 1/4 mile anyways, so it really doesn't matter.

 

Yes it sure can ... Been there done that got the low et to prove it
Shouldnt but can
Doug

 

This is true, but I allways turn it off anyways. I guess it is just part of my routine now.

 

Mine shifts into 4th sometimes before crossing the traps!

 

Mine shifted into the "4th" at each pass (5 passes total) and yes...it did hurt my ET. BUT...can it harm the transmission?

 

How freakin' fast are you guys trapping such that you're actually shifting into 4th.

I don't hit 4th until well past 110mph. The only reason I turn off O/D is to get some engine braking and avoid the slam shift into 4th letting off at 106+/-

 

Mr. Moderator says it shifts into over drive in the quarter, Don's Bolt says it doesn't. Mine doesn't either. Sounds like some on here are running the wrong rear end gears if it's going into OD before the finish line.

 

I would just leave it on. If your truck is going to shift into OD on the 1/4 mile it will but if don't need to it will just stay on gear to the end of the run.

I wish mine would go into OD on the 1/4 but that would mean I would have go past 135 mph cuz that when 3-4 shift happens at WOT (special request I made to JPL)