Whats happening to my 700R4? - Third Generation F-Body Message Boards

PeterFeix · 08-25-2007, 07:20 AM

Hi!

When my transmission is downshifting from 2nd-1st gear, there is a loud knocking, but only when the shifter is on D.
In O/D this knocking is almost not noticable.
This sound is just while downshifts and gear changes when the car stands still.

I replaced my tranny mounts ( now energy suspension , my previous mount was ripped in 2 pieces )

would be great if someone could help me with that problem...
what could it be? tcc? converter?
must be something that is differrent in D + O/D.....

today i tried to shift manually, the loudest shift noise is from 3rd to 2nd gear. in "D" it seems that the 3->2 downshift is way too late, ~ @10mph , after that, my tranny shifts immediately to first gear, i think....

greets from germany
alex

gapimpin · 08-29-2007, 08:29 PM

mine does the same thing but mine has been built with every pressure mod there is and the tranny guy said when i have it in any other gear than o/d its got full line pressure. so 200psi when its downshifting is gonna make some noise... dont know if yours is stock or if its the same way on a stock tranny.

PeterFeix · 09-01-2007, 03:20 PM

thanks for your reply,

i don't think that i have a built tranny...
in 2004, the pre-owner of my car replaced the tranny for about 3500$.
this should be a stock tranny, the parts in europe are much more expensive...
but i don't know if its really stock.....

maybe i'll find it out someday...

greetz
alex

gapimpin · 09-02-2007, 03:58 PM

you could always check the tv cable and make sure its not too tight... i know that would make clunking noises upshifting dont know if downshifting does it too though...

Fueler · 09-03-2007, 08:07 PM

Mine did the exact same thing,turned out it was the u joint on the driveshaft.

PeterFeix · 09-04-2007, 01:40 AM

so i'll order new u-joints , perhaps it is really exactly the same thing....

next week it should be done... i hope so