Transmission Shifting issue: need help please

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http://www.electricaladvantage.net/4...fits4l80e.aspx

I'm not sure what the difference is between the first two kits (except price).

Gents, I've been reading your posts trying to find the possible solution to my problem. Here we go.....I've left my house ( errands to the store)and the tranny shifts hard between 2nd & 3rd. It happens Up shifting and down shifting. This is the catch, when I return home, there are NO hard down or up shifting and none the the issues you are guys are having; like flickering lights or slippage. This only happen on the first drive of the day. FYI. I had the transmission serviced last week. They cleaned the screen , flushed the system and retop the fluids. I revisited the shop today and talked to the manger about my problem. He insured me that the service they did was text book. He even said that it had been serviced not to long ago and the insides look great. Any idea?

@TexasVX2015

Might be far fetched but look and see if you have an AutoTrans Interceptor electronic shift modulator, (shift kit), installed.

http://www.vehicross.info/misc/misc_...ptor_thumb.jpg

Good Luck

Will do. Thanks

A word of caution and something to watch for depending on your mileage if the POs did not flush the system and you have now done so it could be an issue.

Several members have experienced transmission failure after flushing a system that had not previously been flushed.

Hope all goes well for you on this one.

Also, make sure that the shop topped off the the trans fluid correctly. Our transmissions have a very specific way that they need to be filled. They need to be brought up to temperature, topped off, shifted through the gears, topped off, etc. If all of that wasn't done then you may be low on fluid which might be causing the hard shifts.