Torque converter. I may need a new one.

cbielat

cbielat

Senior Member
I'm hearing and feeling a rough sound coming on when the truck is on load. It does it at 60mph and beyond even with slight press on the gas pedal. I feel the torque converter isn't locking and is constantly slipping. How could this be when the truck just hit three years old? Anyone else have this issue?
 
Register to hide this ad
A750E/F failures are pretty rare. Does it do it at lower speeds than 60?
Does the TC lock when not under load, like coasting down hill?
Does the trans slip from low speed with large throttle input?
How many miles?
Does it do the same thing in 2wd and 4 hi?
Have you checked U joints for wear?
Have you greased U joints regularly?
 
Seriously doubting TC going bad.

Have you had it diagnosed yet? I'm guessing the techstream can force a tc lock for diagnostic purposes.

If I was to guess, I would think more like Ujoints or something in the diff.
 
wfo9 said:
Seriously doubting TC going bad.

Have you had it diagnosed yet? I'm guessing the techstream can force a tc lock for diagnostic purposes.

If I was to guess, I would think more like Ujoints or something in the diff.
Click to expand...

From what I was explaining to my techs, they seem to think it's the torque converter. We'll be checking it out and running scans on Monday.
 
I've had all of the fluids replaced and greased everything about a month and a half ago. I am hoping that it's not something as severe as this but it's seeming like it just may be.
 
Agreed - "Slipping" would indeed point to TC or other issues with the trans (low hydraulic pressure?). U-Joints and diffs won't "Slip"...

cbielat said:
I've had all of the fluids replaced and greased everything about a month and a half ago. I am hoping that it's not something as severe as this but it's seeming like it just may be.
Click to expand...


Hopefully it's just over/under filled. Apparently our transmissions are very particular about proper ATF levels...
 
cbielat said:
I've had all of the fluids replaced and greased everything about a month and a half ago. I am hoping that it's not something as severe as this but it's seeming like it just may be.
Click to expand...
If you had the trans fluid replaced a month ago, and the problem started since then, I would look to that fluid change as the most likely suspect. Did they use Toyota WS ATF, and was the fluid level set properly (in temp check mode).
 
The reason I thought not TC, was the statement about 60mph and above. But I'm just guessing here over the internet.
 
Jeremy556 said:
If you had the trans fluid replaced a month ago, and the problem started since then, I would look to that fluid change as the most likely suspect. Did they use Toyota WS ATF, and was the fluid level set properly (in temp check mode).
Click to expand...

Yes, and temp gauge is in the same spot it has been since day one. No dash lights have come on, no check engine light.
 
cbielat said:
Yes, and temp gauge is in the same spot it has been since day one. No dash lights have come on, no check engine light.
Click to expand...
What I mean is, when changing the trans fluid, the fluid level has to be set at a certain temperature, in a check mode. Improper fluid or level is unlikely to throw a code, but will cause all sorts of problems.

You should check the fluid level and make sure it is correct. Here's a PDF of the procedure.
 
Jeremy556 said:
What I mean is, when changing the trans fluid, the fluid level has to be set at a certain temperature, in a check mode. Improper fluid or level is unlikely to throw a code, but will cause all sorts of problems.

You should check the fluid level and make sure it is correct. Here's a PDF of the procedure.
Click to expand...

Correct. This is what I was discussing with one of the top techs I have. We are going to go over it on Monday.
 
Torque Converter

Hope it`s not the torque converter, but if it is, see in a high stall version is available. Not a street race type, just a little higher stall speed. I did this on a tow car and it gave a lot better pull from start-up, then acted normal. Could be good for our heavy T4s.
 
BobsTrail said:
Hope it`s not the torque converter, but if it is, see in a high stall version is available. Not a street race type, just a little higher stall speed. I did this on a tow car and it gave a lot better pull from start-up, then acted normal. Could be good for our heavy T4s.
Click to expand...

I'm planning on using an oem torque converter. Thanks for the info. I'll take that into consideration. I'm not exactly sure what you mean. I'm not that well versed in this part of the truck but, soon I will be lol. Never had I ever had this issue with any vehicles.
 
Jeremy556:

Thanks for the 2010 A750E/A750F PDF.

It's my understanding that the A750E is fitted to 2WD models; A750F to 4WD models. I have the 2WD.

Page 4 of 11 - A750E - shows an A/T Oil Temp light that's activated after the shift sequence described on that page.

Page 9 of 11 - A750F - shows that Indicator light {D} remains illuminated for 2 secs then shut off.

Late model Tacoma's with the A750E/A750F work this way. My 2015 Tacoma 2WD has an A/T Temp Light in one of the dash clusters. My 2014 2WD 4 Runner does not have an A/T Temp Light.

I may be wasting my time, but I'm going to jumper DLC3 pins 4 and 13 and engage the shift sequence. Curious to see if an A/T temp Light illuminates that hasn't so far. Could be that the D - Drive shift position indicator light - will illuminate as some have reported on a Tacoma forum.

If none of this pans out I'll end up using Techstream or a Scan Gauge to get TFT - transmission fluid temp.
 
One of my co-workers has an 12 Tacoma & he was talking about the clamshell bushing in the front axles & said this fairly common failure 1 Was wondering if this MIGHT be what's going on here ? Not enough of a wknd mechanic to help with diagnosis , just a thought ! I hear a little noise down there kinda of a what they call "rumble strip" on 4th gens !
 
Whatever came of this problem, [MENTION=76550]cbielat[/MENTION]? Did you replace the TC, and did that solve the problem?
 
You must log in or register to reply here.

Members online

Total: 640 (members: 1, guests: 639)

Forum statistics

Threads
278,315
Messages
3,554,104
Members
248,016
Latest member
Advally Service

Share this page

Trending content

Back
Top