question about shifting gear

[katana1981]

Hi everyone.. I have an Intrepid with a 2.7L engine for 4 years now... 253500km on it.. no problem with the engine or anything else... except this:

the problem started last night... I drove on highway..

first gear to second, sweet...

second to third gear, sweeettt...

third to fourth gear... oups.. it sliped for a sec than went to fourth...

fourth to overdrive... sweet...

I tested again and again.. its only between third and fourth that the transmission slips for a sec than goes on fourth gear... but my problem is that it doesn't happen everytime... only once in a while... can you help me with that please?

BTW, I've only use Mopar atf or aft +4 fluid and change the trans filter and oil every 40 000km...

Thanks in advance, Mark

[theFREAKnasty82]

what color is your fluid? Since, you have approximately 157,200 miles, your transmission could be getting a little worn out. Make sure your level is good as well.

[AWP9521]

Is this during light throttle acceleration or full throttle? Reason I ask is sometimes the ECC (Electronic Converter Clutch) engages in 3rd and sometimes it doesn't depending on the acceleration rate, if the ECC locks up in third it will release just before shifting into OD (about 40 MPH or higher depending on the rate) and then engage again, you will see a spike in the RPM when the ECC disengages then it slightly lowers for the shift and then drops again when the ECC engages and might make you think it's slipping, this is actually normal operation.

[katana1981]

my fluid color is red.. brand new btw...

and the trans slipped when in half or full acceleration only..