grindin in first gear while pulling out from a stop

[79mustang]

My 02 gt has a problem with a grinding noise while pulling out from a stop. I have no problems getting it to shift into any gear. Only does it in first gear... Also seems to get worse the longer i drive. I've replaced the flywheel, clutch, pilot bearing, and throw out bearing not too long ago thinking one of these parts might be the culprit, but it still does it. Its pretty darn embarrasing to pull out while people are around cause its fairly loud. Any ideas of whats wrong? I've been looking around the internet for a rebuild kit for my tranny (t-3650), but im not having much luck. i saw d&d performance has a rebuild kit but its $650. seems kinda high.
also there a place called american powertrain that sales whole rebuilt t-3650 trannys. has anybody had experience with them?



Thanks
Tim

 

[tonytaylor85]

EDIT: i reread your post and might be confused. does it grind going into gear or as you release the clutch to start moving? My post below assumes it grinds going into gear.


Sounds like the synchro is going out. Cold fluid helps the synchro slow down the input shaft and go into gear. as it heats up the fluid doesnt help out.

Can you shift while stopped into second, and then without releasing the clutch go into first without it grinding? If it doesn't grind, it is almost for sure your 1st gear synchronizer.

If it still grinds it must be your pilot bearing binding and still turning the input shaft while you try to shift. This would probably affect other gears but would be most noticed from a stop I imagine.

Synchro and bearing kits can be had for ~$300 but the transmission has to come out and come apart. You'll need a well equipped shop if you want to try it yourself.

 

[79mustang]

as you release the clutch and start to move from a dead stop it makes a grinding noise. Doesn't grind in any other gear but 1st. I'm kinda confused about what your saying about shifting from 2nd back into 1st. are you saying to try that while im driving down the road and see if it grinds???

 

[tonytaylor85]

No- that was to diagnose a different problem.
I don't know the specifics of the 3650 so I can't diagnose but grinding under power is never a good sign. Time for a rebuild. I say pull it now before something breaks and takes the rest of the trans with it.
Ebay has rebuilt units for ~$750 but you could possibly get a used one from MPS (they are local to me and always have a nice supply) for around 400.