NEED HELP Hard shifting and no speedometer

Bushwacker

Original poster
Member
Oct 1, 2018
3
Northeast California
We have a 2007 Trailblazer SS, 6.0 ltr, AWD with 130,000 miles on it and just experienced an issue with the speedometer and transmission. The speedometer stopped working and the transmission shifts harder now then usual. Everything else on the instrument cluster works fine, including the tach. Any thoughts on what to look for?
 

Mooseman

Moderator
Dec 4, 2011
25,224
Ottawa, ON
CEL on? Any codes?
 

Mooseman

Moderator
Dec 4, 2011
25,224
Ottawa, ON
Yes, start with that for the P0720 and see if that clears both codes. P0700 is much more ominous as it may indicate a fault with the TCM.
 
  • Like
Reactions: Bushwacker

Bushwacker

Original poster
Member
Oct 1, 2018
3
Northeast California
Thanks guys, I'm looking at the speed sensor also due to the fact that it was just driven and then parked. Once fired up again it threw the code. The correct code was PO 722 not the 720 I originally posted.

Greatly appreciate your comments!👍
 

Forum Statistics

Threads
23,256
Posts
637,330
Members
18,448
Latest member
Bluecorp

Members Online