Originally Posted By: i_hate_autofraud
On your'04 Buick LeSabre + 4T65E:
1) I'd consider a fluid and filter change AND get more magnets to go on the oil pan where
the diff is (towards right side) there's not a lot of room on the pan anywhere else, since it is zero
clearance and the filter sits on the pan.
2) 2 yrs ago I put neodymium bar magnets on the filter it's self on the metal next to the oil pick-up,
I used a compass to make sure the N pole faced the same way, making the metal plate the S pole,that helps pick
up lots of wear metals before they contaminate the shift solenoids and Pressure control solenoid.
This spring I'll drop the pan and see how it went while I'm in there. I'll take pics.
3) For slow / delayed shifts I've been using Seafoam Trans Tune, my 4T65E is so bad over time, that
40% of the ATF is Trans Tune! It looks like it thins out the ATF so valves & solenoids will cycle.
4) If you can get it to improve, watch out for other problems to showing up, like delayed / harsh shifts, often
shift accumulators with new stiffer Trans-Go 4T65E shift kits work well, does in mine.
5) See these PDFs on 4T65E:
GM 4T65-E COMMON TRANSMISSION PROBLEMS
https://app.box.com/s/n3eaao2pzopusd3bx8qrd7xmgaibj3n1
GM 4T65-E TRANSMISSION UPGRADE PARTS
https://app.box.com/s/drsf61akkxu6bw2a2qcnl1ajuhgkh9hx
Are those articles written by you? ......You could remove all the negative slander & just present what seems to be decent information. I could post some pretty slanderous things about Sonnax & Trans Go!