Search the Community
Showing results for tags 'tcc'.
-
2017 Silverado LT 5.3 4X4 6speed transmission 51,000 miles When I first bought the truck the transmission suffered from severe bucking or shudder under light load. GM calls it chuggle. The cause was "intermittent tcc delamination causing scoring on fluid pump". They replaced the torque converter, cover housing and pump cover along with a flush. This was at 10,000 miles. That seemed to solve the chugging problem. For the last year or so I have noticed that the torque converter unlocks and locks frequently at freeway speeds. When it locks, following an unlock, there is a noticeable lurching forward. This is not neck snapping but is definitely noticeable. This lurching motion also occurs when upshifting 4/5 or 5/6. While driving at freeway speeds (65 70mph) when I slightly let off the accelerator the rpm's rise about 200 then settle down. If I should slightly press down the same thing happens. However, when driving at a steady freeway speed, and holding steady on the throttle, on level ground I can feel this unlock/lock along with seeing the engine speed move up then settle down. If I engage cruise control on level ground it is worse and occurs more often. But, with cruise control on and there is a slight road incline there is no unlock or downshift. When I press hard on the throttle then it downshifts and accelerates fine. Locking/unlocking and lurching; I do not recall the transmission behaving like this in the early years. The dealer says if it doesn't throw a code then it is operating normally. I can see that there are times when it should unlock such as when under load, but should it be this happening this frequently and be so noticeable? Or maybe I am being too sensitive? Anybody experience the same thing? Is this normal transmission behavior?
- 13 replies
-
- 6l80
- transmission
- (and 4 more)
-
Hello all! First post here! What brought me here was the 8l90 torque converter lockup shudder issue. Most times I'd just take this truck to the dealer and let them sort it out, but as it's out of warranty, this is not something I'd like to pay >$600 to repair (this price was quoted to me for the flush and filter change). After talking to a few service advisors I've found that each of them planned on using a different solution to attempt to alleviate the shudder. The first was going to proceed via one of the bulletins and do a triple fluid swap and filter change, the others were just going to do a standard flush and fluid swap. I plan on owning this vehicle for another few months until the 19's become a little more negotiable but cannot stand to let this shudder go on that long and am a bit worried about destroying the torque converter in the process and washing a whole bunch of parts down into the transmission. So.... my question is if anyone has performed this fluid swap themselves, if it alleviated the issue, and if the filter change is necessary? I saw that many of the Corvette guys were swapping to the Mobil 1 fluid with some success, however, I didn't think this was as much of a fluid performance issue as it was a suspended clutch material / dirty fluid issue. Any help would be greatly appreciated!!!!!!
-
So I was heading home from work and decided to fuel up with 91 octane and used the fuel system cleaner at the pump. Approximately 20 miles out of town my truck started to surge and the RPM's jumped on every surge. I thought it was the fuel until. The next day I stopped at a stop sign and when I eased my foot on the pedal the transmission acted like it was not engaged in 1st gear and then slammed into gear. I found a transmission at a wrecking yard but I'm not sure what caused this and am afraid the problem may still exist with a new tranny. Has anyone ever experienced anything close to this?
- 7 replies
-
- 6l80
- tcc lockup
-
(and 5 more)
Tagged with:
-
I am having two issues with my 2000 GMC Sonoma 2.2L 2WD single cab pickup truck. It has the 4L60E transmission in it, which is what is causing issues. It currently about 146,000 miles on the truck itself, but has a rebuilt transmission in it with about 60,000 miles. The reason I replaced the transmission the first time was because it wouldn't shift out of first gear and there was a loud cranking, grinding sound. Reverse also wouldn't work. I first noticed issues with the original transmission during a 400-mile road trip across generally hilly terrain. I wasn't towing anything, nor was it loaded with much except a large suitcase and my wife and I. About midway through the trip (traveling 60-70 mph), what I believe was the TCC failed to engage. I'm a complete noob when it comes to transmissions and TCs, but research on the web led me to surmise the TCC was the issue. As I was in the fourth gear, the RPMs jumped up from 3k to 4k, with no change in the accelerator position. I was not at WOT. The tachometer would remain at the higher RPMs for about 30-60 minutes until it would randomly drop back down to the normal cruising rate. This cycle would repeat multiple times throughout the trip there and back. Not realizing there was a major issue (and being pretty broke), I didn't have my truck checked. About a month later, the transmission did the grinding, clanking sound and went caput. That's when my mechanic recommended a transmission replacement. That was about six months ago.Two weeks ago, I took a job that requires me to travel about 20 minutes on a 70 mph interstate to get to work and back. I also drive the entire time throughout my 8-hour work day. The temperature outside has been nice (70-75 degrees), and I'm never revving the motor past 3k RPM. So that's the history. Sorry for the lengthy explanation. I wanted all the facts in there. Here's the two problems I'm encountering. 1: Hard shift into second gear. The transmission jerks when it shifts into second gear, but it doesn't happen all the time. It seems to happen after I drive for a while, or travel at interstate speeds after cruising around town for a bit. The odd thing about this is that when I turn off the truck and let it sit for about five minutes, the problem disappears, and doesn't return for more than an hour or two. When it happens again, I just park, turn off for five minutes and continue on until the next time it begins shifting hard. 2: TCC disengaging again on interstate. This has only happened once and it was today. But I don't want to destroy another transmission waiting to figure out the issue. I was traveling home, and at about halfway through the trip of 20 miles, the RPMs jumped from 3k to 4k at a cruising speed of 68 mph. Again, there was no change in the accelerator and I wasn't running WOT. But I had driven the truck for about six hours straight (minus a stop here and there for restroom, lunch, etc.). When I got off the interstate, the hard shift into second was even more pronounced. I then pulled into the nearest parking lot, let the truck sit off for five minutes, and the problem vanished. Side note: The SES light came on about three weeks ago, stayed on for three days and went off. Earlier this week, the light came back on. I haven't checked the code yet. That's this weekend's task. I will update the post with the error code when I get it. Soooo... Anyone have a clue what's going on? I sure don't.
-
- 4l60e
- transmission
-
(and 4 more)
Tagged with: