Casper3rdgenTL

Backround; 2007 Acura Tl 3.2L 5AT. Just recently had a rebuilt engine swapped in and everything is great on that end. Also right before that I had a tranny flush done with new fluid, But now my transmission is being wierd. From 1st to 2nd it shifts smooth. It's 2nd to 3rd that's the real issue. It's like it hesitates for a half second and I lurch forward and the RPMs spike up THEN it shifts all within a second or less. The gear change itself is fine, no clunking or anything. Same for 3rd to 4th but not as bad. 4th to 5th is smooth again. My mechanic said that it's gonna be the new norm because the new engine is more powerful than the previous one causing the transmission to shift like that to protect itself. Idk if I should just believe that though. He gave me some lubegard atf protection additive to put in so I put half that in with no change. Any advice is appreciated! Is it possible that's it's as simple as the pressure switches? It seems like a different problem than that cuz it's not hard shifting. Just revving up before.

PgLgGrg

I had a very similar problem. I took ownership of my Dad's TL he owned from 2016. No ATF change in that period, and possibly few years before that as well. 2-3 shift was hesitant and lurchy, 3-4 same but not as bad.

I changed 4/7L with new Honda ATF DW1. Shifts are much better now. i imagine if I did a full flush or 3x3, it would be even better. Considering replacing the pressure switches, but nothing OEM thats available for a good price. Options on amazon though
Did you out in a J35 engine from type S or 4th gen TL? Else how is the engine he put in more powerful?

TheSauceBoss

So, your original engine was rebuilt? Why would it be "more powerful" than the previous one? If anything, it should be back to factory spec, which the trans can handle just fine. On top of that, I'm concerned your mechanic told you to put in an ATF additive, that stuff is basically snake oil.....

You need to get more info. Was the original fluid change actually a "flush"? Or was it a drain and fill? Can you actually confirmed the fluid was changed? I was going to ask what the condition and level of the fluid is, but with an additive thrown in there, it's going to be hard to get data from.

Your symptoms could be a result of low//dirty/improper fluid, or the clutch packings could already be damaged. HOPEFULLY it's as simple as a 3rd and 4th pressure gear change, but you don't want to start throwing parts at it if it's not going to help. Also, for what it's worth. ONLY buy OEM pressure switches from a honda/acura supplier. There are a good amount of stories on these forums of people buying amazon/ebay "OEM" switches only to have them fail shortly after installation, or not work to begin with.