97 silverado transmission will not shift into overdrive.
vandamn
05-14-2011, 04:51 AM
hi
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
MT-2500
05-14-2011, 07:52 AM
hi
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
First thing you need to do is get it on a good transmission capable scanner and see what is going on.
If any codes post back code no.-no's. engine or transmission past or present or history codes.
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
First thing you need to do is get it on a good transmission capable scanner and see what is going on.
If any codes post back code no.-no's. engine or transmission past or present or history codes.
j cAT
05-14-2011, 08:33 AM
hi
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
getting those DTC drive train codes is needed to narrow down the component. most likely the transmission pressures are dropping when throttle is light at hywy speed...this DTC would be P1870 ...If so its a good chance the TCC valve body is worn out..kits are available to repair this.
what is the mileage on this transmission ? what fluid did the rebuilder use ? what parts did he replace ? did he flush out the tranmission coolant lines, and replace the torque converter ?
having problem with 97 silverado transmission.will not shift into overdrive. happens when transmission is warmed up. will happen sometimes from a stop or at highway speed will downshift out of overdrive. somewhat intermittent not all the time. truck is 5.7l and recently transmission rebuilt year ago with 5000 miles since. any info or help appreciated.
mike
getting those DTC drive train codes is needed to narrow down the component. most likely the transmission pressures are dropping when throttle is light at hywy speed...this DTC would be P1870 ...If so its a good chance the TCC valve body is worn out..kits are available to repair this.
what is the mileage on this transmission ? what fluid did the rebuilder use ? what parts did he replace ? did he flush out the tranmission coolant lines, and replace the torque converter ?
transman618
05-17-2011, 10:37 AM
Check your codes first and post any code/s back here and we can go from there. Now, if its overdrive thats dropping out what you will need to do is monitor the live data on the scanner and see whether 4th gear is commanded by the computer. A scanner needs to be on it while driving and when O/D falls out see if the computer is still commanding it. If you are getting the command then your problem is most likely in the 2/4 band servo. Most likely a leak in the 4th piston.
transman
transman
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