My 06 shifted hard and it was cured after both filters were changed. Probably around 100K
Yea, but did you have codes:
p0700 transmission control system
p0732A gear 2 incorrect ratio
p0845 transmission fluid pressure sensor
p0750 shift solenoid A malfunction
p0733 gear 3 incorrect ratio
p0735 gear 5
p0734 gear 4
p1521 manufacturer controlled vehicle speed (idle speed)
He definitely has a problem here, it might be a bad sensor totally confusing the TCM and throwing these codes. He could have a trans totally chewed up and about to fail, throwing these codes from mechanical malfunctions.
Changing the fluid and filter, can't hurt, despite some idiots insisting it might.
Fluid that has sheered and degraded from use, clogged or leaking filters, can cause malfunction from pressure problems in the hydraulics or rough clutch engagements, etc... So in some cases fresh fluid and filter would solve these problems.
Unless all these codes come from transient states during clutch engagements, that are slipping because of pressure or degraded fluid, he others things wrong with the trans. Hopefully its the combination of bad fluid/filter and a bad sensor.
Sadly, it could be the trans is suffer sever mechanical malfunctions and has damage, I hope that's NOT true, but its possible.
If I was a general mechanic, and I saw those codes, I wouldn't touch the trans either and tell you to take it to a trans expert or the dealer, that is better able to diagnose the problem and repair it. A general mechanic would know it is possible your trans could fail any minute and just changing fluid and filter won't change that, but the mechanic would open himself up to liability if it did fail after he serviced it, even if it obviously was NOT his fault.
When you get the pan off, if there is all sort of goop, sorta like a grease or soft putty, sparkling matter, even pieces of metal. That is bad news, you've likely got lots of mechanical damage. The soft putty material, that is almost like grease, is usually worn off friction/clutch surface materiel. Its normal to have a little bit of it in the pan, usually collected on the magnet in the pan. But if you have tons of it, like all over the pan, that means all your clutch material has worn off and they are worn out now.