anyone ever thought about an O/D button?

Didn't some grand cherokees come with buttons on either the shifter or steering column that would turn off the overdrive for towing? My dad had one a while back and I vaguley remember this feature. Am I just making this up or did they really have this? If so was it an AW4 and has anyone tried to convert this over to a cherokee?

why not just drop it down to 3 on the shifter?

To be honest this idea started while daydreaming today on the way home because I haven't regeared yet the jeep is a liitle sluggish on the highway. I guess 3rd with the overdrive would be the same as 4th without though.
:doh: