my 1999 chevy s-10 blazer has an hard shift from 1st only after an long out of town drive & no check eng lite?

Question

i got an 1999 chevy s-10 blazer 4.3 eng/4l60e trans around town runs fine.but if i go on an long out of town drive.it shifts hard from 1st to 2nd.no check engine lite is on,ive already jus changed the oil & filter. i even scaned it wit the obd 2 scanner to see if any codes in memory.nope,none mechanic at the trans says valves or springs could be geting hot & causing it to shift hard ? PLEASE HELP dont got the money to buy new trans.someone said something about whole new valve body ?

Answer 1

Have the codes checked again, these models are known for P-1870 trans code-component slipping,which is nearly always t-converter slipping after extended highway driving.The TCC reg valve wears out in v-body causing this code ,and the result is higher pressure commanded by the pcm to correct the slippage.the result is always 1-2 bang shift after stopping and taking off again.Seen this many times before but it does not always turn the cel on.

Answer 2

Did the oil and filter inside the trans have any sparkly silver in them? If so, you've got a tranny coming apart. Did the trans. get flushed or just a change of the bottom pan oil and filter. If so , there's still about 4 gallons of old fluid in there. You might be having trouble with a internal seal or spring in the accumulator either leaking or broken. This will be either in the valve body or the side of the trans. Fairly easy to access. More diagnosis is required here which means to start some disassembly to inspect. Good luck.

Answer 3

could also be your govenor binding when it gets hot. Since its easy to remove and extenally accesible, seems sensible to check first. Check for smooth operation by hand.

Answer 4

buy a transmission cooler and have it installed they are cheap and will double the life of your transmission