Yeah, I'm a newbie guy, 2 cents on me.... long time automotive engineer in the GM/Delphi world , wrench it geek, motorcycle crazy.

Hey all, my car is a 2004 Buick LeSabre that was my dads and I inherited it, with 20k mile, now 51K
It has a clunk on light throttle on the 1 - 2 shift - very annoying.... that I am research and finding out is common.
Also finding out that adding a TransGo Shift kit will eliminate the clunk and improve the shifting.
Sometimes on hwy speed and a quick throttle lift will do the same thing.
I am a pretty good wrench guy, but trannys are something I wont touch.
Looking for a guru within driving distance of Dayton Ohio that could do an install.
I could (1) purchase and assemble the accumulator housing and shift kit components separately and it would be a black box install.. drop pan, filter, OEM accumulator, replace with new, reassmble.
Or, (2) Bring the shift kit components to the tranny guy and then he could install the kit at his location.
Really want to get this done, as I know from being in the GM engineering eco system, this tranny has a higher than average fall out.
Any ideas?

Thanks to all.

Do you do engine work other than oil changes? If you can pull the pan you can do this job. An automatic transaxle is not to be feared.

Yeah, pulling a pan and filter would be no big deal and I have watched YT vids on it, and it doesnt look all that hard. But really dont want to spend an afternoon on my back, maybe if I had a lift.
Guess there is a first time for everything, but prefer help from some who has done it.
I like working on motorcycles..... cars.. not so much anymore.

I would have a reputable shop in your area do the work for you. Anyone can come along on the Internet and say "Yup I'm great at this, done millions without a single issue" then show up at your house, do it poorly, offer no guarantees or options for remediation, leave, then come back in two weeks to rob the place.

I hear ya... the key is reputable....

Any tranny shop can do it.

Here'* what I'd do: I'd ask some of the reputable general auto repair shops in town where they send their transmission work.

Installing this kit is something any shop should be able to do.

I'm just not sure about the diagnosis. Hard to tell what the "clunk" is between 1 and 2 from across the Internet. Could be a bad motor mount for all I know.

The car had really low miles when I got it 21K crazy near showroom condition, and it did it then. And since I have put 30k miles on it, I am sure its a tranny thing.
I also have been trading notes on a Buiick forum that others had the same in common.
I am totally good with doing this shift kit thing. Jegs has it.
Also, If I go the black box direction, I can pick all the parts up from Rock Auto there, put it all together and its an easy job from there.
Goes like this.... (Warning.. geek engineer foole)
You need 1 of: 24227726 (the lower housing) 24205584 (the upper cover) 24205621 (the main gasket)
You need 2 of: 24206857 (piston includes seal) 24203979 (pins) 24203977 (upper piston springs)
There might be a few other pieces to go with that...
You'll need 7 M6x25mm bolts to bolt the upper cover to the lower housing.

I might see if I can get some lift time locally and go DIY. Although really dont want too. In my driveway is a no go.

BTW...Is there an "edit" function on this forum? Cant find it. Wanted to correct a typo.