'99 Ford Ranger refuses to play nice

First things first … This post is in regards to '99 Ford Ranger XLT 3.0L FlexFuel Truck … When i put the vehicle into Drive, it takes about 15 secs to auto-shift into gear … if I step on the gas at any point before the shifting has occured it will not shift into gear at lower rpm’s and forcefully buck into gear at higher rpm’s … this occurs at startup and/or any time the truck is idling (ie, … at a stop light/sign) …And, curiously enough, this does not occur in Reverse, which shifts beautifully. I’m planning on changing/replacing the trannie fluid and filter and checking the valve body gaskets for wear this next weekend … Just curious, though … am I barking up the wrong tree? Thanks for any and all help/opinions

If the fluid is at the proper level, I’d get it scanned for transmission issues before I bothered to change the fluid and filter. You may be looking at something serious, but then you knew that before you asked.

What does the transmission fluid look and smell like? Brown and burned toast?

First step: Find an honest transmission shop. Avoid “chain Stores” like scAAMCO.

I agree that it is a transmission issue. If you don’t know a good transmission shop, ask your friends and neighbors for one. If you have a mechanic you trust, ask him for a transmission shop recommendation. How long has it been (miles) since the last transmission fluid change, and how many miles on the truck?

See if engages in L1 if so, then the Low /reverse sprag clutch is suspect. Next try to see if it engages in D with the O/D off button pressed. If it does then the O/D sprag clutch is suspect. There are others but these are the smplest tests w/o tools.