bad synchros :(

[ChosenGSR]

Hey guys, my M3 has bad synchronizers thanks to the previous owner who was under the impression that the clutch stop should be all the way out. Of course the clutch was never fully depressed during the shifts. The car only has 85k on it, but the synchronizer issue is fairly obvious. Anything over 4k and you feel/hear the synchronizers "rolling marbles" sound. Mostly apparent in 3rd gear. I am going to change the fluid just to see if it'll help some, but I know that the transmission needs work.

I suppose my options are to:
1) DIY. (would like to avoid)
2) get a shop to rebuild it.
3) buy a used one, with a limited warranty.
4) buy a rebuilt one, with "extended" limited warranty.

Anyone with some experience in the matter can walk me through my options/costs and what is involved?

[1996 328ti]

You might want to use BG SynchroShift II instead of Red Line or whatever your preference is. I found my tranny running through the gears much smoother with the BG.

[odortiz]

Hey guys, my M3 has bad synchronizers thanks to the previous owner who was under the impression that the clutch stop should be all the way out. Of course the clutch was never fully depressed during the shifts. The car only has 85k on it, but the synchronizer issue is fairly obvious. Anything over 4k and you feel/hear the synchronizers "rolling marbles" sound. Mostly apparent in 3rd gear. I am going to change the fluid just to see if it'll help some, but I know that the transmission needs work.

I suppose my options are to:
1) DIY. (would like to avoid)
2) get a shop to rebuild it.
3) buy a used one, with a limited warranty.
4) buy a rebuilt one, with "extended" limited warranty.

Anyone with some experience in the matter can walk me through my options/costs and what is involved?

before replacing the trans, try using redline 75w90 NS. the ns fluids make synchros come to speed faster. i have played with these fluids to help cold shifts and it works. since the fliud is thicker, it may take a minute ot two of easy driving to get the fluid warm enough (that's only in 40 deg and colder)
i needed to mix ns fluid because i am using a thicker gear oil to quiet my trans rattle from the flywheel. the ns helped shifting ease when cold.
easier than removing the trans for the price of two bottles of redline.

[ChosenGSR]

I hear you guys, I am going to change the fluid pretty soon. Rob from UUC suggested Redline 75W140NS as a heavy fluid which typically helps with reducing the "sound" of the synchros and mixing it with Redline D4-ATF, 1:1 mix. However sooner or later (depending on whether changing the fluid will do anything) I'll need to address the real issue, so I want to be prepared.

[jkuper]

Hey guys, my M3 has bad synchronizers thanks to the previous owner who was under the impression that the clutch stop should be all the way out. Of course the clutch was never fully depressed during the shifts. The car only has 85k on it, but the synchronizer issue is fairly obvious. Anything over 4k and you feel/hear the synchronizers "rolling marbles" sound. Mostly apparent in 3rd gear. I am going to change the fluid just to see if it'll help some, but I know that the transmission needs work.

I suppose my options are to:
1) DIY. (would like to avoid)
2) get a shop to rebuild it.
3) buy a used one, with a limited warranty.
4) buy a rebuilt one, with "extended" limited warranty.

Anyone with some experience in the matter can walk me through my options/costs and what is involved?

If you do need to replace, find a used tranny, option C.

[ChosenGSR]

If you do need to replace, find a used tranny, option C.

I am leaning towards that choice as well, however if the price difference is within 2-3 hundred dollars, does it make sense to go for a rebuilt one?