Transmission is shifting funny

I have a 2001 Tacoma 2wd Prerunner double cab with an automatic tranny. I've had it for about three months now and whenever I shift from park to drive the truck pretty much bucks. I used to drive a stick shift Celica so I'm not sure if this is normal or if I should be worried.
I'm also averaging 13mpg on stock tires which seems pretty low to me but then again this may be normal for this truck.
Please let me know if these things are normal or not and what to do.

 

Not normal on both counts. Do you know when the last time the tranny fluid was changed? If you don't then do a drain and refill x3, that should get most of the old fluid out. Drain once, drive it around and make sure to go through all the gears, repeat and repeat.

What's your mileage? I think it's time for a major tune-up like plugs air filter, oil change etc.

 

It has 72,000 miles and I have no idea when the tranny fluid was changed last. Thanks I will have to check and see and hopefully find sometime to get all of that taken care of.

 

mine bucks in gear also but only when the truck is cold, and i just assumed it was from the idle up to warm the engine but i might try and trans flush


Ryan

 

If all else fails, B&M Trick Shift.

 

After doing the tune up and lube change and your mpg's still suck. Try clean your throttle body and MAF, and then you may have a faulty AFR sensor.