Ever since I changed my transmission my speedo has been indicating the wrong speed. Well I know this is due to the fact that I only used my old driven gear and din't replace the gear on the output shaft. My speedo has been indicating 10 mph faster than I am actually going. Now thats not a problem for me but now My speedo acts crazy and sometimes doesnt even work. My torque converter lock up goes in and out at random times. And I got a code for the VSS. So did my VSS just go bad or would the wrongs gears have caused the VSS to go bad. There is also the possibily of the cable being faulty. IDK what do you guys think? I just don't wanna buy a new VSS and have it go bad again.

 

My guess would be that you are using the wrong speedometer housing. A tranny shop told me that if the driven gear is 34-39 teeth then you need one type of gear housing and if the driven gear is 40-45 teeth you need a different housing. Something about the 30 series gears being shorter or maybe longer than the 40 series and if the correct housing isn't used it could cause the speedometer to not work or work sporadically.

I'd say count the number of teeth on the drive gear and then we can tell you which driven gear and housing you'll need. Also need the tire size and axel ratio.

Or you can try to use the same driven gear and housing that were in your old transmission and that may make it work consistently but the mph will still be off.

It's also possible that your speedometer cable could be going bad. I'd say find out how many teeth are on your drive gear and go from there.

 

i dont think the housing makes a difference, i went from 2:73 to 3:73 and i was "supposed" to get a different housing, but didnt and everything workes fine. only certain drive gears go with any giver driven gear, you may have a set that is not made to work together. its not hard to replace the one on the output shaft, just get the right one and do it. took me less than an hour the first time i did it.