Hello all,
Quick simple question, I hope....

I have a 2006 6MT TSX. Its stock so far. Its a heavy daily driver, but I have the Honda mental illness and can't leave it alone...

I think I want to put a PNN4 transmission in it. ('06+ Civic SI 6MT). Same 1st, 6th, and final drive as the TSX, with shorter 2nd-5th gears. Sounds like fun.

My question is - is it assumed the build quality in all the K-series transmissions is the same? They just changed the gear ratios to suit the application?

I ask because I like how buttery my TSX is through the gears, and I don't want to swap in a transmission of lesser power capacity (not that I think I'm going to exceed it) or crappier syncros, or something like that.

This question is inspired by a random post by an unknown user on a board I forget about the PNN4 giving people trouble. Helpful, I know.

Opinions?

 

The synchros are identical inside both transmissions: triple cone 1/2, dual cone 3/4, single cone 5/6. Ratios will differ, and as such, technically, strength differences *CAN* be different depending due to slightly different modules employed by the designers to reach the selected ratio with a fixed shaft center-to-center distance. But this is negligible in the scheme of things.

With that said, the casings are WAY different between the two transmissions, so the only hope you have of attaining those ratios would be to swap the ratios into your transmission housing. Which isn't too difficult of a procedure. This method would also allow you to pick and choose the best synchros between the two gear sets to use at the same time.

If people with PNN4s have issues with the transmissions in comparison to TSX transmissions, they should look inward to the drivers of the two transmissions. Much like RSX owners, Civic Si owners abuse the hell out of things. It will wake your car up though for sure. I did an RSX Type-S 1-5 gear swap into an all motor, 270+ whp TSX. Made it great. Then we recently put a 5.0 final drive in it. Thing definitely rows through the gears.

 

Wow, glad I asked - I never would have thought the tranmission wasn't a direct swap!

thanks

 

I am in the midst of doing this myself. I know this thread is almost 8 years old!!

Apparently you can take the internals out of the Civic SI tranny and swap them into the TSX!

I do not believe you can simply swap the gears alone as you will require the input shaft from the SI tranny!

If anyone else knows more on the subject, please chime in! I am looking into buying a used SI tranny with the OEM LSD and swapping the gears and LSD into my 06 TSX!

 

You can swap 3-6 and the FD. If you want to swap 2nd, then you have to swap both 1st and 2nd and shim the mainshaft. Check the shim clearance on the countershaft when swapping gears. The LSD will also need to be shimmed.

 

Thank you so much for the prompt reply aqua! It seems to me like the most simple option is to transfer the internals from a k20z3 tranny and just swap it into the tsx! Less work it seems!

Sourcing one with lower km is a challenge. Found one at a junker with 160,000km (100,000 miles). I do not want to blow a ton of money buying all new oem parts for the complete k20z3 tranny from Honda either. If anyone has suggestions, please let me know!

-Clint
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