dka99burb
Member
This is a continuation of a discussion we were having a while back in the 6.5 area about studdering at cruising speed. Turns out that I believe the TCC lockup was causing this issue as it confuses the cruise control.
Here is the data that I hope will help:
1. 1999 K2500 Suburban with 257k miles
2. Purchased this summer
3. No SES light.
4. Fluid level okay.
5. No Codes.
6. Fluid was brown and smelled terrible when I first started working on it. I have changed the fluid twice and the filter once.
7. Speedometer seems to be reading correctly. I have not verified with the GPS but it is close.
8. Transmission is shifting normal.
9. I have replaced the solonoids and wiring harness in the pan(kit from Advantage Electronics suggested in this forum) trying to fix this.
I don't think it really matters but I have replaced wastegate vac solonoid too.
10. Driving to work; 25 miles, mostly highway.
11. Typical weather. North Carolina: from 98 down to 70 recently.
My friend and I finally got together and connected his big scanner. I am not sure of the brand. We drove it and monitored. Shifting looked good, input and output sensors read as I would expect, trans temp stayed around 165, forcing the TCC with his scanner worked fine too. What is happening is the TCC locks whenever APP% is above 8% and unlocks as soon as it drops below 8%. I am only at 8% if I am climbing a hill or accelerating. Cruising speed is only around 4% APP. This was the only correlation that we were able to note. Does anyone have any experience with one doing this? Do you think it is the APP? The voltages look pretty close to what I have read they are supposed to be. Any suggestions will be appreciated.
Thanks.
Here is the data that I hope will help:
1. 1999 K2500 Suburban with 257k miles
2. Purchased this summer
3. No SES light.
4. Fluid level okay.
5. No Codes.
6. Fluid was brown and smelled terrible when I first started working on it. I have changed the fluid twice and the filter once.
7. Speedometer seems to be reading correctly. I have not verified with the GPS but it is close.
8. Transmission is shifting normal.
9. I have replaced the solonoids and wiring harness in the pan(kit from Advantage Electronics suggested in this forum) trying to fix this.
I don't think it really matters but I have replaced wastegate vac solonoid too.
10. Driving to work; 25 miles, mostly highway.
11. Typical weather. North Carolina: from 98 down to 70 recently.
My friend and I finally got together and connected his big scanner. I am not sure of the brand. We drove it and monitored. Shifting looked good, input and output sensors read as I would expect, trans temp stayed around 165, forcing the TCC with his scanner worked fine too. What is happening is the TCC locks whenever APP% is above 8% and unlocks as soon as it drops below 8%. I am only at 8% if I am climbing a hill or accelerating. Cruising speed is only around 4% APP. This was the only correlation that we were able to note. Does anyone have any experience with one doing this? Do you think it is the APP? The voltages look pretty close to what I have read they are supposed to be. Any suggestions will be appreciated.
Thanks.