2nd Gear Problems
 

Please forgive me if this is a stupid question. I've searched the crap out of this and still haven't been able to diagnose my problem. Any help would be greatly appreciated.

Symptoms:
When I shift up to 2nd the shifter starts to vibrate and if I continue to pull back it will grind. This seems to go away when I shift at less than 2k RPM, when I double clutch, and when I keep the shifter pressed to the drivers side as I shift. It seems more pronounced when it's cold.

Background:
I recently bought an 08 Speed3 with 34K (it now has 36K). Since I've had it I put a Cobb SRI and a Sure Torq R3 RMM on it. I should also note that this is my first manual so I was not easy on the trans during the first few weeks of owning it. I started noticing the problem a few weeks ago and thought it was driver error. As time has gone on I have noticed it getting worse and now think that it's something mechanically wrong. I took it into the dealership last week hoping they would fix the problem and they changed the trans fluid and told me it was fixed, while it improved things it didn't fix them. The dealership said that it may be caused by my RMM, other fixes I was considering were adjusting the shifter (via: MAZDASPEED 3 How to Fine Tune Your Shifter JBARONE Short Throw Shift Plate - YouTube), swapping out the shifter bushings, or switching fluid to Motorcraft xt-m5-qs.

If it grinds at higher RPM the syncro most likely is slipping as it tries to slow down 2nd gear.

A bent shift fork usually makes a clunk as 2nd is engaged. i believe 1 & 2 are tied together by a single fork. (plz correct if I'm wrong, I know you will :))
If you have no issues in first then i would rule out any fork (Clutch or shift).

You should try adjusting the shifter. stupid easy to do. you typically want to to be more left. switch to motorcraft and try the bushings. I would avoid the plates as they can alter the cable travel. use it as a last resort.


But honestly, if it grinds every time over 2500 rpm its most likely the syncro for that gear.

You said you installed a RMM. Do you grind or have difficulties in any other gear? maybe its not level.




In the mean time SKIP 2ND GEAR!!!!
run to 4000 in 1st and 3rd should shift into around 2,100-2,200 rpm. you have to wait a second longer before you left off the clutch.

The rmm doesn't affect shifting, neither does the engine not being level. The trans is cable shifted.

The 1-2 shift fork is 5lb of iron, you would probably break the shifter cable before you bend the fork.

There is a nylon pad that goes between the fork and the syncro and it will fail in every trans.

The best advice that I can give you is use the motorcraft fluid, change it every 25k, shift from 1st to 3rd and swap that shift fork out. Its a ~$120 part + trans removal and the fix require basic hand tools and can be done by any mechanic that can follow basic instructions.

If you break the 2nd gear syncro the price goes up 3x or more and requires a trans shop to rebuild the gear cluster, but thats only if you dont ruin the trans by running brass flakes through it.