NB 5 speed issue downshifting from 2nd to 1st?

[Keifersmith]

The 5 speed transmission on my 99 NB seems to be hard to downshift from second to first gear without grinding unless I'm either stopped or almost to a stop. I just assumed that a synchronizer was getting trashed but POS Racing seemed to think it might be a common issue with the NB transmissions. Anybody else with an NB have an issue like this?

Just looking for another data point in trying to decide whether to fix a lot of stuff on my NB or swap out the engine/transmission.

[Majik]

I think that is pretty common.

[bmcreider]

I'd say that's common...

[tailchaser]

Sounds like your car is trashed. I'll give ya $2.50 for it!

I don't think I've ever even tried to downshift to 1st without double clutching (so no grinding), but it's pretty likely to get some complaints from the wheelhouse on any unaided shift from 2nd to 1st.

[trickyrix]

Not sure if this would apply to you, but I had the same problem with my NA. A change to fresh, synthetic fluid (Motorcraft Full Synthetic) made it MUCH easier to shift between 1st and 2nd.

[Keifersmith]

Not sure if this would apply to you, but I had the same problem with my NA. A change to fresh, synthetic fluid (Motorcraft Full Synthetic) made it MUCH easier to shift between 1st and 2nd.

Yeah I did the fluid change to Mobil 1, new shift boots and turret fluid a few months ago. I does shift smoother but didn't fix the 2nd down to 1st shifting problem. If I double clutch it does better but still sometimes will grind anyway. No point in going to a lot of work/expense if it's a common problem.

[Swiftracing]

Same for me when I changed to Motorcraft synthetic. Much better. One thing to note, the first gear synchro is a different type of synchro than the rest of the box. Its made that way because normal drivers only shift into first at a full stop. Its called a standing synchro. It takes a bit more finesse to get it in smoothly. I always double clutch the shift into first. Limits the crunching. Changing the fluid helps alot as well. just my two cents.

[Maverick]

I've run into that 'feature' as well. Solved it by not downshifting into 1st unless I'm almost at a complete stop.

[CarCar]

My NB does the same 2nd to 1st. I use Motul gear 300 75w90 and that helped. The shifts are much smoother overall but you do get more gear box noise but I kinda like hearing the gears sing.

[jeff_man]

question, why would you ever down shift in to first other then at a stop or is the problem when your stopped? i know the 6 speeds has kinda a soft first gear lock out when the car is moving.

[the_don]

well once I have the same problem yall got... its normal just avoid it

[CarCar]

Patient: Doc, it hurts when I do this. OW!
Doc: Don't do that.

[Radio-Active]

well once I have the same problem y'all got... its normal just avoid it

You hit the nail on the head.

[Keifersmith]

question, why would you ever down shift in to first other then at a stop or is the problem when your stopped? i know the 6 speeds has kinda a soft first gear lock out when the car is moving.

There are times when I have slowed down significantly but haven't come to a complete stop yet. 2nd seems to bog down at low RPMs (Probably due to another issue I've listed with my car ) so I like to downshift to first. There's no issue if I'm totally stopped or just barely creeping when I downshift. my NA doesn't seem to have this issue so I assumed that my synchro on the 99 was going.

Swiftracing, Thanks for describing standing synchro. That explains a lot. Guess I'm not a normal driver

Anyway, Thanks everyone for your feedback. Guess it's just something I'll have to live with.

[MiataMike]

Yes, definatelly normal. I've owned 4, 1999-2000, MX-5's and they have all been that way.

[POS Racing]

Keifersmith simplify your life and get a nice Automatic miata then you can put it in "D" and forget all your troubles!