transmission/computer issue

Howdy i have a 2014 tacoma 4.0 5 speed auto trans 6 inch lift on 18inch rims 33s.
i have strange problem with my truck it only has 3000 miles on it and when driving on the highway it can not Decide what gear it wants at the speed range of 65-75 mph
It will be fine then it will sit and bounce between gears i have taken it to the dealer 3 times and met with toyota engineers and there clueless any ideas would be apreciated

 

Read here http://www.tacomaworld.com/forum/2n...-transmission-low-fluid-directly-factory.html

and here http://www.tacomaworld.com/forum/te...hift-kit-shift-recalibration-kit-2nd-gen.html

 

I checked the fluid level and it was fine. It has been droping gears now and it dont like to go in to 5th gear i have to trick the cpu into shifting any ideas ? I wanna say its the torque converter the dealer keeps saying my truck is at max load capacity due to my lift kit and tirez witch makez no sence at all
Any ideas would be appreciated

 

You truck only has 3000 miles on it?? And you have a 6" lift and 33" tires?

Your transmission was not designed to run 33" tires. Your gearing is setup for stock tires - not 33's. It's a no wonder your ECU/Computer are confused. It still 'thinks' your running stock tires.

You need to start researching about putting different gears in your differentials.

 

373s in both diffs. Does it being a v6 make a differince. Cause i had a 1970 gmc jimmy with a 6inch lift 35s it had 373s but a v8? I didnt lift this 1 btw its a dealer lift this is my second tacoma the last 1 was wrecked when the truck grew a mind of its own and went into 4x4 low at 70 mph