Dealership can't figure out what the heck is wrong with my Taco.

I have a 2006 Tacoma 5 speed auto that I bought brand new with a 60k mile power train warranty. At ~48000 miles, I began to experience a shudder at lower RPM gear changes. I thought it was an ignition problem the torque converter was putting extra load on the motor and making some ignition flaw evident. I replaced the plugs with top-of-the-line iridiums to no avail. After another thousand miles or so, I began feeling a sensation like I was driving over rumble strip before gear changes. After some research, I found there to be a TSB stating that a bad transmission mount was the cause. I was skeptical, but took the truck to the dealer. The dealer replaced the mount, and obviously did not road test, because the problem was still as evident as ever. I live a pretty busy life, I took the truck home and drove it another thousand miles or so. The problem(s) were getting more severe each day. I took the truck back to the dealer, and they found a bulletin stating contaminants in the tranny fluid are causing bad shifts. They flushed the tranny 3 times, and filled it back up. They said the magnets in the trany pan were clean. This actually seemed to fix the problem for about 500 miles or so, then the issues gradually came back to their former glory. A new issue arose. The truck would herk and jerk at the 2-3 and 3-4 gear changes at slower speeds. At my earliest convenience (which took weeks), I got the truck back to the dealer. The service manager told the the tranny was toast, and he would put a new tranny and tq converter in. He said the issue was that improperly meshed gears created particulates in the fluid, which clogged to the solenoids, creating poor shifts. They gave me a rental car and kept my truck for nine days. When I got my truck back, all was well. ~800 miles later, the shuddering and rumble strip issues come back. I took the truck in two days ago and let one mechanic drive it. He thought the shudder was either the U-joints or the driveshaft itself (this truck has a 2 piece shaft), and the rumble strip issue was something in the differential. He was talking like they would not try to fix it, but rather replace everything behind the tranny(!). I brought the truck back today and drop it off and let the service manager drive it. He thinks part of the problem is the tq converter 'fluttering' and is puzzled about the rest. He told me they will bring in a specialist from corporate to look at my truck and will probably have it for some time. What do you guys think the issue could be?

-JUS-

 

What dealer are you seeing?

my truck would shake from 10-20mph, and all of my u joints where trashed.

 

just got my u joints replaced as well. i was having a vibration or shuttering while driving and taking off and it was noticeable at all speeds but very prominant at just under 60km/h and highway speeds.. ONLY when there was a load on the drivetrain, even very subtle ammounts of pressure would casue this shake. they replaced the u joint and it rides like new.

 

Ernie Palmer

 

I couldn't tell you but it sounds like the dealership is definitely working with you on it. Be thankful about that. I'd hate for you to be one of those people that complain and get no where with growing frustrations. Good luck though. Let us know what they say. I hope your rental is another Tacoma.

 

The dealership called this afternoon to tell me they had put a new transmission in it again. The service manager said it was contaminates in the fluid, which caused an issue with a solenoid controlling the tq converter, which caused "tq converter flex". The contaminates were supposedly left over from the first transmission, because they failed to flush out the cooler and lines when they put in the second transmission. I do not see how there could be enough contaminates in a cooler to get past the filter and ruin a solenoid so quickly...but what do I know? I asked about a break in period on the new unit, and he told me there is none, because Toyota broke it when it was REMANUFACTURED.

Lets hope transmission #3 is the best of the bunch.

 

woah 3rd tranny?
wow

 

Did they replaced your U-joints ?

 

Nope.

 

Ok you have prerrunner right, with 60 k miles on original u-joints. I am going to site with your last mechanic saying your u-joints are crap.
Dont be upset you are not first prerruner like that
get them replaced and report back.

 

On the side note, they probably replaced the first tranny for nothing which sucks because who knows what tranny they gave you afterwords

 

The trans. could create that shudder if the trans. started gear hunting while in lock up.

 

***ZOMBIE THREAD UPDATE***

To finish the story from 2010, the third transmission they put in my truck was trouble free for 60k miles. Last week, the exact same issues arose! Clunky shifts at 2-3 and 3-4, with a "rumble strip" hard shift into 5th.

I took it to the dealership and they said replace the transmission (imagine my surprise). Instead of plopping down $4400 for a FIFTH transmission, I opted to see a specialist. I took the truck to a very well respected transmission shop in town. He pulled the pan and told me the fluid was "clean as a whistle." He did say the EPS could be bad, causing abnormal fluid pressure. We replaced the solenoid and serviced the unit, but nothing changed. He said he was baffled, but was convinced that nothing was mechanically wrong with the transmission. He thought it was actually a computer problem, and the tranny was just trying to do what the computer told it to.

Tonight I made a discovery. In trying to avoid the awful 5tg gear shift, I dropped the shifter into 4. The truck ran beautifully with very smooth shifts into 3rd and 4th. When I shifted back to D, those same gears clunk. What could be causing this?! I think it IS the PCM, and perhaps there was never anything wrong with the previous transmissions.

Ideas?

-JUS-

 

sounds like the tcm might have a short in it. could also be a shifter cables being short or kinked to make the tcm think it in between two gears. possibly a bad ground even.

 

I had what sounds like the same problem when tranny would shift from 4th to 5th under load. Turned out to be a cracked spark plug. I know you said you replaced em but it might be worth it to pull em and inspect them for hairline cracks.

 

If you can manually shift the transmission into 4th and everything go back to normal I would pull the valve body to verify that it is in good condition. If it is in good condition I would end up going through the wiring and looking for shorts. After going through 3 transmissions I'd say you probably have some type of electrical problem. Check your grounds as this commonly is what is often neglected and a culprit to alot of problems.

 

I agree with 2.7 taco. I think you have an electrical problem somewhere

 

Sounds like it's a ford...

 

Cut your losses.

 

It actually sounds like a Chevy. A friend of mine has a shop and most late model GM vehicles are doing ridiculous things electrically and transmissions in most cases fail to a point where only the transmission case was salvageable. My personal experience with late GM vehicles has been pretty rough especially with the electrical side. Had the car quit blowing AC while driving down the road and the thing going from AC to full heat without touching the knobs. Not to mention overly sensitive ABS system and poor brake bias.