I'm looking at purchasing a truck. Truck in mind is a 2007 F-150 Screw Lariat. While on the test drive the truck had shuttering at 3-4k RPMs. They sent the truck to Ford. They replaced the torque converter. The truck has 55k miles on it. What would cause the torque converter to go bad? Any reason to worry about purchasing this truck? Having to worry about the transmission being next?

This is the truck in mind.
http://www.autotrader.com/fyc/vdp.js...standard=false

-Curtis-

 

look somewhere else.who knows.my trans was replaced at 53k.plantery gears went BOOM

 

With all of the used F150's that are out there, I'd just walk away from this one and find another.

 

That's $6K less than what I paid for my truck brand new. I've got ~40K on my truck. I'll sell it to you for that!

 

Probably a good idea to walk away but to answer your question the following are likely TC failure causes:
1. Broken turbine or impeller blades.
2. Worn TC clutch.
3. Spalled impeller side needle bearing.

Those are the top three failure modes that we dealt with when I was in TC engineering at Ford.

 

3. Spalled impeller side needle bearing.

Bingo, that is what is wrong with mine. Whine in gear only. Certified Transmission shop told me to save the $ for a complete rebuilt and drive it until it starts getting worse. IMO, If I was going to replace the Torque converter, I would do the whole tranny. Look elsewhere.

 

In retrospect I should have qualified my statement as to why you may want to consider passing up this purchase based on the fact that the TC was replaced. If the failure was any of the three items that I had referenced above there is a high probability that the entire trans system has been contaminated with shavings from the TC. In other words, the trans, lines and TOC cooler (if equipped) are likely to have some degree of debris in them and will continue to circulate through the system for its entire service life unless they are completely removed and replaced OR flushed. I'm not even 100% certain that flushing will purge the system of all the debris. Granted, the transmission filter should pick up the debris to some extent but I strongly feel that it will always reside to some extent or another within the transmission itself.

This is just my thought and suggestion. Take it for what it's worth and use it for your final purchase decision.