It's been almost 10 years, but I'm back into the Thirdgen fold again. Bought a 89 IROC over the weekend, loving it.

So, anyways, one of the only quirks with this thing is it will upshift into 3rd gear but not downshift into 3rd. If you're coming from 1st or 2nd, it will go into 3rd no prob, but if you're coming from 4th or 5th, no dice. You can try to downshift into 3rd but it's like it is gated and won't allow it. I haven't yet tried slamming it into 3rd, but it certainly won't push into 3rd like any other gear in that situation.

I've searched and checked out the FAQ. Stumped on this one. Any ideas?

 

Could be a fried third gear syncro? Are you trying to rev match your downshifts? When downshifting from 4th try putting it in neutral, let the clutch out, rev the engine, then clutch & shift into third, this will bring the speed of the input shaft closer to the speed of the output shaft and may reduce the work that the syncro is trying to do. If that works, I'd say your syncro is probably toasted

 

Very interesting, I will try that. Thanks for the tip.

I've got a lot to learn about manual transmissions. Reverse can occasionally be interesting as well (very rarely) so I'm wondering if it also has syncro issues. Guess I'll be taking it easy on the T5 for the time being.

EDIT: Read on a Mustang forum that T5 has no reverse syncro but you've got to go to first before going to reverse. That sounds like my problem.

 

That's correct, reverse is not synchronized. Make sure the car is at a dead stop and hit any forward gear before you hit reverse, I usually hit 5th, then reverse, just because 5th is right there.

 

I agree that it sounds like a synchro. I also agree that you should try double clutching (as described earlier). Also, try a rev-matched downshift into 3rd and tell us what happens.