Does anyone elses 6mt grind when in 4th gear shifting into 6th or via versa? I don't ever remembering this ever being an issue until now. Also it feels like the car grinds if it does not have perfect engagement into 2nd and 3rd. I thought by having the dealer put in a new clutch and fly wheel would fix the issue. Any ideas?

 

Do you mean every gear 4th -6th? 4,5,6 grind or do you literally mean 4th then 6th? I can see going from 4th to 6th up shifting getting on the freeway but I can't see any good reason to drop from 6th gear speeds to 4th without killing something. That may be why you are grinding

 

Bad synchros.

 

if i am on highway in 6th gear i dropped to 4th to pass someone is that bad?

 

I get that from 4th to 5th gear.

 

Had my tranny replaced under warranty for the exact same problem. My problem was 5th gear and only when the oil was cold. Left the car overnight with the dealership and they had a tech drive it the next morning. They confirmed the problem and replaced it free of charge.

 

Depends on who you ask. IMO..yeah, bad idea. 6th-5th should be sufficient enough to pass someone. You are putting a lot of stress on the trans at that speed going from 6-4...the RPM range is pretty drastic for an instant grab. So cruising at like 65mph you are probably sitting around 2100 RPM (give or take) then you drop to 4th at that point your RPMs shoot to like 5-6k. That is a lot of stress

 

Even with a good rev match?

 

Same here.
Started after I took my car to get my headlights fixed

It doesn't happen all the time -- but I can't rly do the quick shifts to 5th anymore. I have to be more "delicate"

No issues from 4th to 6th here... in fact I do this more than ever now to avoid 5th...

Really? I should see if my warranty will cover this too! My oil is definitely not cold though.

I do this often. Sometimes 5th is not enough.
I wouldn't say it's "bad" but def more stress than going into 5th.
I always rev-match before doing this though.

 

thanks for the feedback

 

^ what? how are you getting your math? 60mph puts the 6th gear at ~2200rpms (just a bit more). in 5th, this is ~2800rpm. and in 4th we are at ~3600rpm. this is just simple math using the gearing of our 6MT gearboxes.

it is very reasonable to drop from 6th down to 4th while cruising at legal speeds on the highway. going from 2200rpm to 3600rpm will not hurt anything. in fact, this gets you much closer to peak power which could be critical to complete a passing maneuver, for example. heck, even dropping to 3rd would only put you at 4600rpm.

if you only drop down to 5th you won't get the acceleration needed if the passing must be done quickly. of course a guy will rev-match as close as he can with a blip of the throttle. that's all part of why we drive 6MT to begin with, and knowing how the car will react and where your rpms will be is all part of the fun.

 

Great response, what i wanted to hear thanks bro.

 

6th to 3rd downshifts to pass quickly are normal. If it hurt a transmission I would have had to replace mine 2 or 3 times by now. I wouldn't go down to 3rd when cruising at 80, but if you're going that fast you won't really have need to a quick acceleration pass in normal driving.

 

I was just guestimating the RPM and assuming he is only going 60-65. I was using it just as a frame of reference. I know my car doesn't like that major down shift.. granted I dont ever need to pass anyone that vigorously. But like Betty said, at high speed I would not be shifting like that.

 

So i take it everyone is just fine shifting from 6th to 4th without any grinding. Must be synchros