5R55S Quick Question

Emily's Mustang

New Member
Aug 13, 2020
I recently purchased an auto 2007 Mustang GT.Well I pulled into a gas station this morning and some guy came up to me saying how he liked the paint job and then started talking about how he had an 08' auto for a few years and somewhere in the conversation we ended up talking about the transmission a little bit. He said that when I go to pass someone on the highway I shouldn't just put the pedal to the floor because it can mess up the transmission somehow and that I should instead turn off o/d first then pedal to the floor.I have never heard of doing this on any auto car so I'm taking it with a big grain of salt but I just wanted to make sure this wasn't true because I certainly don't want to hurt my transmission.Thanks.
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Active Member
Jan 25, 2020
Well, it's something I do anyways. I turn the OD off on all three of my Fords as soon as the vehicle is running. And don't turn it on unless I am going faster than 55. I live in a large city of mostly 35, 40 and 45 mph speed limits. OD is useless at these speeds. Also, my Lightning. It's always been said on these supercharged trucks to turn off the OD before mashing the pedal to the floor. Whether it be passing at high speed, or taking off from a light or stop sign. Going into OD from third at full boost is just about a guaranteed way to enter the ventilated block club on any Lightning that isn't stock.

My Mustang hunts in the 40 to 50 mph range if in OD. Can't make up it's mind if it wants to be in 4th or 5th. Especially in hilly terrain. Turning off the OD stops the hunting. It's just something I am used to doing.

But seriously, I doubt it's going to hurt the transmission on a normally aspirated vehicle. Boosted, better safe than sorry.

Anyhow, for longevity of the brakes, I like to downshift my vehicles even though autos. Use the engine for braking. Been doing it in my 98 Ranger for 20 years. My Lightning for 11 years. Hasn't hurt a thing. And, since I downshifted them to stop, I tend to manually shift them when I take off again. The Rangers intake and exhaust are tuned to like high rpms, higher than the computer shifts them. The Lightning makes beautiful music when manually shifted, makes the blower louder.