1st gear trouble
 

I am having issues with my 1st gear. I have to come to a complete stop to put it in, otherwise it just grinds. It also grinds if I put it in from neutral to 1st while stopped. I have tried double clutching and it still just grinds. 5th gear also grinds if I take it out and have it in neutral to coast, then put it back in at speed. I'm guessing the synchros are going bad, but I am not sure. Is there anything I can do on my own? Thanks for the support.

Here's a BMW Technical Service Bulletin:

Service Information - Bulletin Number 23 01 99

SUBJECT: Manual Transmission Difficult to Shift - Diagnostic Tips
MODEL: All with Manual Transmission
SITUATION: Transmission may be difficult to shift especially first gear
engagement and/or gear shift linkage is binding. Note: Field observations
have indicated that a transmission which is difficult to shift (especially
into first gear) is primarily a clutch related problem and only in isolated
cases a failure in the transmission itself.

PROCEDURE:

Verify the customer complaint:

Note: Engage the parking brake and assure that no people or objects are in
the vehicle's path.

- - Run the engine at idle speed
- - Press the clutch pedal to the floor
- - From the neutral stick shift position engage first gear

If first gear is difficult to engage, hold the stick shift at the
resistance point (approximately half of the total stick shift travel) with
constant force.

Then switch the ignition off with the other hand.

DIAGNOSIS 1:
If first gear now engages completely, i.e. the stick shift moves to the end
position without any additional pressure applied, there is a problem in the
clutch system.

Explanation:
Because the clutch does not uncouple completely, a residual torque is
transmitted to the transmission input shaft when the engine is running.
This inhibits the release and meshing of the sliding sleeve, in the
transmission, at the end of the synchronization process. Turning the
engine off relieves the input shaft of this torque thus simulating a
completely uncoupled clutch.

DIAGNOSIS 2:
If the stick shift remains at the resistance point, there is a problem in
the external gear shift linkage or in the transmission.

CAUSE:

DIAGNOSIS 1:
Possible causes for a clutch problem as per Diagnosis 1 above are:
- - Input shaft taper splines not lubricated properly/grease dried out.
- - Clutch disc difficult to move on transmission input shaft.
- - Clutch disc wobble.
- - Air in the hydraulic system of clutch mechanism.
- - Release bearing defective or difficult to move on the guide sleeve.
- - Clutch disc or pressure plate broken/worn out.

DIAGNOSIS 2:
Possible causes for gear shift linkage binding and/or internal transmission
problems as per Diagnosis 2 above:
- - External gearshift linkage binding (shift rod joints stiff).
- - Stick shift bellows boot incorrectly installed (positioned too high or
too low on the stick shift lever).
- - Sound deadening between the outer gear shift linkage and the body
incorrectly installed and/or distorted.

Possible causes inside of the transmission:
- - Faulty synchronization.
- - Internal gear shift linkage binding.
- - Water in the transmission fluid. (rare)

Thanks, I appreciate the help! I'll try that tonight. How much would it be to repair the synchros?

from stand still... try going to 2nd (first) - then from 2nd go to 1st & see if it still grinds... Sounds kinda dumb, but my old car used to grind when going directly into 1st, but never when going from 2nd to 1st.

That's what I do now. It never grinds if I go from 2nd to 1st, but sometimes it just doesn't want to go in.

When was the last time you changed your transmission oil?

My car would sometimes refuse to go into first gear when stopped, but without any grinding. This went away when I switched to Redline MTL.

Hi This is my first post, Just a thing i have found on a number of occasions, do you have a mat or something up under the clutch pedal? This may seem obvious but it can happen.