2002 103k miles. Ap2 trans with 90k miles. Comp stage 2 clutch. Oem flywheel. Aem intake. Everything else stock. Fresh synchromesh

Hey guys need some help.

S2k shifts beautifully every gear. Any rpm. Any speed. Except 4th. Shifting into 4th is a dream. But when I try shifting at 9k to 4th, it hits a brick wall. Doesn't grind. Doesn't make any noise. Just simply won't go into 4th until rpms drop to around 6. Tried adjusting clutch, made no difference.

Also another weird thing if I'm stopped, I can go I to any gear aside from fourth. If I'm in light, press clutch and try to shift to 4th it won't go. Any other gear is fine. If I shift to third first then 4th without letting go of clutch it's perfect.

I'm just lost. I don't think its synchro because it doesn't grind, it basically just acts as if there is literally a wall between 3-4.

Things I tried but didn't work:
Gm synchromesh
Adjusting clutch
Regreasing shifter.

Oddly if the trans is cold it doesn't have this issue. HEELLP ME.

 

Sounds like syncho issues.

 

Sounds like a burred 3-4 gear collar. Do you skip gears when shifting?

Wide open throttle operation in 4th gear (full accel and decel) can flatten the burrs and cure it.

 

I never skip shift but maybe the previous owner of trans did.

 

I have a 20 mile drive to work. I'll try n stay in 4th majority of the tjme

 

I was going to look for a similar post from Billman! Great advice and probably a good place to start.

 

The only thing is my car gets into 4th fine if I'm under 7k rpm

 

How many times do you need to do this for it to help? Does it depend on the size of the burrs?

Is this a recommended procedure every now and then for pro-active maintenance to keep gear collars in shape?

 

Bump

 

Synchro problem for sure . You could try and exercise it and slowly increase the rpm's everytime you make the shift . It may sort it self out . Remember don't try and shift too fast . Good luck !