Strange Phenomenon

[Ryan]

So, I can't explain this:

I'm tooling around in my 5 speed in the snow. If I slam the brakes, and lock both front wheels, It WILL NOT go into 1-2-3-4-5 without grinding. It will, go into reverse. Meanwhile, if I'm letting the tires roll, either backwards or forewards, it will go into 1-2-3-4-5 easy, but not reverse without grinding. This is always clutch fully in, no synchronizing attempts.

It stumps me.

Only things I can think of are
a) Wheels aren't locked completely
b) I'm not on the clutch all the way, but I'm quite sure I am.

[Daninski]

Solution
A. Don't slam the brakes on
B. Don't roll the car if you want to go into reverse.
There that was easy.

The grinding while going into reverse dosen't sound abnormal from cars I've driven if the trans is cold. One solution could be to put a lighter oil in your trans/differential. As the trans gets older the syncros don't work as well as new ones.

[Ryan]

Oh Danny, you're no fun at all sometimes.

Yeah, it normally doesn't like reverse. Its not synchronized in my particular tranny.

[Daninski]

Sorry forgot to mention that if your clutch isn't completly disengageing it can cause the issues you spoke of as well.

[nos92mx3]

how are your motor/tranny mounts?

[Ryan]

Um. Well they still both sit where they're supposed to be... So I'd guess still O.K. but most likely 16 years old.

[nos92mx3]

How much does the motor torque back and forth?

[Ryan]

Never really looked. Just playing with the throttle cable, not much at all, but I realize its different when you're putting it into gear.

[LongJohn]

It sounds like your clutch doesn't fully disengage when also slamming on the brakes. It might also be that something is twisting from all the torque from slamming on the brakes, but I don't think you would get the same symptoms if the shifter linkage was binding. Perhaps something in the clutch housing is binding.

The clutch and brake share the same reservoir, and old fluid will stain it and make it look full when it's not. It's remotely possible that the power assist of the brakes is doing something funny with the fluid. It's good to check anyway, and if the fluid is more than a few years old you should consider flushing it out with new fluid (check the nuances on how to do this before you try it).

Nothing I can think of explains why 1-5 is so different than reverse in this case.

[Ryan]

Me neither. Everything runs fine too. Unless its really cold then she's pretty stiff and grinds seccond no matter what. (really cold = -40 F or a little better)

I just avoid lockup unless I'm having fun. Its good braking practice