Hard shifting after hwy driving is caused by high line pressure due to â??limp home modeâ?. LHM is a result of high ATX temp caused by slippage or slippage detected by the PCM. A bad TSS or VSS can sometimes trick the PCM into thinking the ATX is slipping. They are cheap compared to a new ATX and you would want to use new ones if you install a new ATX anyway, so it wonâ??t hurt to change them. Internally it could be a bad 2/4 band, forward clutch or worn VB
Be warned, sometimes the TSS can be a real problem to remove.
jeff
