Caleb1534
Newbie
When I started our 1994 Chevrolet K1500 Silverado Z71 4WD pickup one day in September 2017 to take a load of trash to the dump, the Service Engine Soon (equivalent to Check Engine Light in today’s vehicles) dashboard light was illuminated. When I shifted from Park to Reverse, there was an audible jolt, and the front left corner of the hood visibly popped downward about an inch or so.
As I began driving, it was very hesitant to upshift or downshift. When I got to the stop sign that’s 7/10ths of a mile from our house, it was refusing to accelerate from a dead stop. In fact, it would barely move forward as I pressed the gas pedal, and it sounded like the engine was about to die. It continued to do this until I chose to shift it into first gear manually. There was then another noisy, severe jolt. It remained somewhat hesitant to shift from one gear to another despite shifting manually.
I continued to shift the transmission manually partway to the dump until it finally began shifting easier in Drive, albeit hesitantly. I made it to the dump without stalling the engine. When I started the engine to leave the dump, the Service Engine Soon dashboard light was off, and the transmission shifted in Drive like it used to do.
I’m afraid this could mean that our truck’s transmission is on its last leg. Is this possible? Or could it be a weird electrical/computer problem that is causing this issue to occur while simultaneously illuminating the Service Engine Soon dashboard light? Now that I think about it, I remember that this issue has happened twice before today, with self-resolution occurring after driving somewhere, turning off the engine, and starting the engine again to come back home. More recently, our truck engine stalled when I attempted to accelerate from a stop.
Also, even when the Service Engine Soon light isn’t illuminated, our truck’s transmission is not the smoothest-shifting transmission.
Does anybody here have any ideas what could be causing our truck’s transmission issue?
I did read that, based on our truck’s symptoms, its transmission could have a worn TCC (torque converter clutch) regulator valve.
Following are the symptoms of that issue:
1. Service Engine Soon light is on (intermittently)
2. Harsh-shifting from 1st to 2nd gear (and other gears)
3. Engine stalls from a stop at times, due to engagement of TCC (similar to a clutch in a manual tranny)
4. Code 1870 is stored on the computer, which indicates internal slippage
Our truck exhibits all of the above symptoms, except that I don’t have an OBDI scanner to check that the code is indeed #1870.
One friend of mine with mechanical knowledge suggested that I replace the tranny with one from a local pick-and-pull junkyard. I’m nervous about doing that because a used transmission could possess the same issues as our truck’s current transmission.
Another friend of mine who’s been a mechanic for over 20 years believes that our truck’s transmission probably needs to be rebuilt. I think that’s not a bad idea, except that the cost may be prohibitive. I’m trying to discover the cheapest, most cost-effective way to fix our truck’s transmission.
With that in mind, I found what looks to be a website with beneficial information about fixing our truck’s transmission, the GM 4L60E 4-speed automatic transmission: www.transmissionbench.com
The above site has info on fixing a worn TCC regulator valve, as well as the parts and tools needed to do so. Including the fluid, filter, and gasket that I’d inevitably need also to purchase, that repair would come to about $288.72.
That site’s owner also has a high-def YouTube series with 18 videos (7.5 hours) of content about rebuilding the GM 4L60E 4-speed automatic transmission.
He also sells a kit for the GM 4L60E which appears to include practically everything needed to rebuild that transmission for $400, with free shipping.
Based on his ‘About Me’ page, he seems to be very knowledgeable about and experienced with rebuilding several automatic transmissions found in American vehicles.
What do y’all think I should do? Any ideas?
Thanks!
Caleb Lewis
As I began driving, it was very hesitant to upshift or downshift. When I got to the stop sign that’s 7/10ths of a mile from our house, it was refusing to accelerate from a dead stop. In fact, it would barely move forward as I pressed the gas pedal, and it sounded like the engine was about to die. It continued to do this until I chose to shift it into first gear manually. There was then another noisy, severe jolt. It remained somewhat hesitant to shift from one gear to another despite shifting manually.
I continued to shift the transmission manually partway to the dump until it finally began shifting easier in Drive, albeit hesitantly. I made it to the dump without stalling the engine. When I started the engine to leave the dump, the Service Engine Soon dashboard light was off, and the transmission shifted in Drive like it used to do.
I’m afraid this could mean that our truck’s transmission is on its last leg. Is this possible? Or could it be a weird electrical/computer problem that is causing this issue to occur while simultaneously illuminating the Service Engine Soon dashboard light? Now that I think about it, I remember that this issue has happened twice before today, with self-resolution occurring after driving somewhere, turning off the engine, and starting the engine again to come back home. More recently, our truck engine stalled when I attempted to accelerate from a stop.
Also, even when the Service Engine Soon light isn’t illuminated, our truck’s transmission is not the smoothest-shifting transmission.
Does anybody here have any ideas what could be causing our truck’s transmission issue?
I did read that, based on our truck’s symptoms, its transmission could have a worn TCC (torque converter clutch) regulator valve.
Following are the symptoms of that issue:
1. Service Engine Soon light is on (intermittently)
2. Harsh-shifting from 1st to 2nd gear (and other gears)
3. Engine stalls from a stop at times, due to engagement of TCC (similar to a clutch in a manual tranny)
4. Code 1870 is stored on the computer, which indicates internal slippage
Our truck exhibits all of the above symptoms, except that I don’t have an OBDI scanner to check that the code is indeed #1870.
One friend of mine with mechanical knowledge suggested that I replace the tranny with one from a local pick-and-pull junkyard. I’m nervous about doing that because a used transmission could possess the same issues as our truck’s current transmission.
Another friend of mine who’s been a mechanic for over 20 years believes that our truck’s transmission probably needs to be rebuilt. I think that’s not a bad idea, except that the cost may be prohibitive. I’m trying to discover the cheapest, most cost-effective way to fix our truck’s transmission.
With that in mind, I found what looks to be a website with beneficial information about fixing our truck’s transmission, the GM 4L60E 4-speed automatic transmission: www.transmissionbench.com
The above site has info on fixing a worn TCC regulator valve, as well as the parts and tools needed to do so. Including the fluid, filter, and gasket that I’d inevitably need also to purchase, that repair would come to about $288.72.
That site’s owner also has a high-def YouTube series with 18 videos (7.5 hours) of content about rebuilding the GM 4L60E 4-speed automatic transmission.
He also sells a kit for the GM 4L60E which appears to include practically everything needed to rebuild that transmission for $400, with free shipping.
Based on his ‘About Me’ page, he seems to be very knowledgeable about and experienced with rebuilding several automatic transmissions found in American vehicles.
What do y’all think I should do? Any ideas?
Thanks!
Caleb Lewis
