Nocking sound from engine or Transmission??

Hello,
This nocking noise from engine or transmission is driving me nuts. I have a 2008 Tacoma PreRunner w/automatic trans. and when I start off driving it shifts from first to second normal, but when it goes into 3rd, theres this nocking noise and lack of power. The noise started about a year ago, very slight, you could barely hear it, but now, you can hear it all the time. It doesnt happen when I first start driving, it happens after the engine has been running awhile and when I do alot of stopping and starting around town. I know the normal Toyota engine sounds, its not that. The noise sounds like one of those old cars with worn out valves climbing a hill, but not as bad. But it only does it when it goes into 3rd gear and I stay at a crussing speed of 35-40 and if I give it gas to speed up, then you can really hear it and then it goes away. The truck only has 44,000 miles on it. Ive cleaned the throttle body, tried all 3 different gas grades and it doesnt matter, that noise happens on all 3 grades. Im running Royal Purpal oil in it (just changed it) before that I was running Moble 1. It seems like the trasmission is not shifting right. It goes into first and second normal, but then it shifts into a gear that makes it bog down. Its like riding a motorcycle in the sand, and your in first gear and you get enough speed to go into second gear, but you dont, you go into 4th gear witch makes you bog down into the sand and your engine makes a tireing noise. Anyway, its driving me nuts. The Toyota dealership wont give me a straight answer. They want my money. Do any of you guys have an idea of what it maybe or have you heard of this problem before? Ive gone threw the forum list and I cant find anything.

PLEASE HELP, Thank you so much, Bill

 

Hello, i dont have the answer for this particular issue but this forum is for new members to introduce themselves to everyone else. You would get a better response if you post this problem in the right forum. Look above and click on "Forum list" and from there you can select where to get a answer for your issue, by the way welcome to TW!

 

Welcome to TW from Sparks, NV

 

Mahalo, I'm new to this. I noticed your from Hilo, I'm from Hanalei Bay Kauai. I miss the islands, can't wait to move back home. Mahalo!