Question about my trans

[97Bowtie1106]

For some reason every time that I drive on the freeway for about 15 miles or more, my transmission shifts hard from first to second when I get off the interstate. The trans was serviced and I made sure the fluid was good but it still does it. Im just curious as to what it may be. Thanks

 

[Bigg G]

that's a 4L60E common problem.... sounds more like an electrical issue to me as long as it's only a harsh 1st-2nd shift.

My truck had a really bad 1st-2nd harsh shift that chirped the rear wheels with very little speed or effort. I changed my TCS switch and dumped 1/2 bottle of Lucas Tranny juice in her and it's much better. Figured I'd just drive her until she slips or start missing a gear before tearing it down.

If the shift is delayed & harsh I'd test or try swapping the TCS or TPS switch .
Also could be a cracked, cocked or stuck accumulator bore piston in the bore which I've heard is a drop pan fix.

 

[97Bowtie1106]

cool thanks...makes sense because my reg cab was starting to do the same thing right before I sold it