Missing a gear shift - ZR-1 Net Registry Forums

Norwegianmopar · 10-02-2020

Once while power shifting from 1st to 2nd I slipped off the clutch pedal and missed the gear causing that awful grinding noise.

Is there any need for worrying, or is the ZF6 trans heavy duty enough to withstand the occational miss?

That sound is like a rock crusher chewing away on those big rocks at the crushing plant.

Luckily for me several buddies was watching when it happened...lol.

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BigJohn · 10-02-2020

I have shifted with out the clutch just to get it home.
That was five years ago; still no transmission problems.

32valvZ · 10-02-2020

Quote:

Originally Posted by BigJohn

I have shifted with out the clutch just to get it home.
That was five years ago; still no transmission problems.

That wont cause an issue at all if your revs are correct. If youre used to driving a stick car you should be able to both up and down shift without grinding... (w/o hydraulic aid)

32valvZ · 10-02-2020

Quote:

Originally Posted by Norwegianmopar

Once while power shifting from 1st to 2nd I slipped off the clutch pedal and missed the gear causing that awful grinding noise.

Is there any need for worrying, or is the ZF6 trans heavy duty enough to withstand the occational miss?

That sound is like a rock crusher chewing away on those big rocks at the crushing plant.

Luckily for me several buddies was watching when it happened...lol.

Sent from my SM-G955F using ZR-1 Net Registry mobile app

As long as its very occasional.... The sound you hear is the brass teeth grinding on the synchro assembly.... which is not great, but theyll survive a few missed shifts...

Norwegianmopar · 10-02-2020

"If the revs were right"...I guess I was in the 6-7000 rpm range (as usual). I have driven it hard and a lot and never missed a gear before, so that's why I ask if it's bad or not.

I love "using and abusing" it as it's an awesome sports car with an amazing power band.Screenshot_20200903-104112_Gallery.jpg

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Mystic ZR-1 · 10-02-2020

Quote:

Originally Posted by BigJohn

I have shifted with out the clutch just to get it home.
That was five years ago; still no transmission problems.

I remember that.
I followed you home to make sure you got there.
As a good friend, if ya didn't make it, I woulda waved to you
as I passed...😀

32valvZ · 10-02-2020

Quote:

Originally Posted by Norwegianmopar

"If the revs were right"...I guess I was in the 6-7000 rpm range (as usual). I have driven it hard and a lot and never missed a gear before, so that's why I ask if it's bad or not.

I love "using and abusing" it as it's an awesome sports car with an amazing power band.Attachment 13100

Sent from my SM-G955F using ZR-1 Net Registry mobile app

6-7k I would say is worse than if you were just driving the car around town casually.. Is it popping out of gear on deceleration? Is it grinding under normal driving condition... if not, youre probably ok.... for now. Keep doing it though and youll need a rebuild...

Norwegianmopar · 10-02-2020

Quote:

Originally Posted by 32valvZ

6-7k I would say is worse than if you were just driving the car around town casually.. Is it popping out of gear on deceleration? Is it grinding under normal driving condition... if not, youre probably ok.... for now. Keep doing it though and youll need a rebuild...

It happened just once, I was full throttle going from 1st to 2nd and my foot slipped off the clutch pedal and I missed second gear, hence the grinding sound. It was all fine afterwards, no problem shifting in any gear.

I just wonder how much wear and tear this grinding may cause...

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32valvZ · 10-02-2020

Here is a video of whats happening when you shift gears. The whole idea of a synchro assembly is to match the speed of the gear shaft with the teeth on the gear itself. So when you "miss a gear", what actually is happening is the shaft and the gears are spinning at different speeds and dont mesh when they should. That causes the grinding sound and since the blocker rings are generally made of brass, they will wear out the fastest. The teeth wear out as well as the cone portion of the blocker ring. I have not opened up a ZF, but many Borg Warners when I was wrenching for a living. We used to rebuild them in house when I worked for Anheuser Busch many years back. The principle is the same.

https://www.youtube.com/watch?v=0Bqs-oHBBQk

tccrab · 10-02-2020

The ZF6 is a very stout transmission, but there are limitations.
Speed shifting won't hurt it a lick.
Missing a gear while speed shifting, we'll not so much.
The 2nd and 3rd gear synchros are fairly delicate.
You will know if they need attention.

'Crabs

10-02-2020	#1
Norwegianmopar Join Date: Mar 2018 Location: Norway Posts: 346	Missing a gear shift Once while power shifting from 1st to 2nd I slipped off the clutch pedal and missed the gear causing that awful grinding noise. Is there any need for worrying, or is the ZF6 trans heavy duty enough to withstand the occational miss? That sound is like a rock crusher chewing away on those big rocks at the crushing plant. Luckily for me several buddies was watching when it happened...lol. Sent from my SM-G955F using ZR-1 Net Registry mobile app __________________ Roy Martin 1994 ZR-1 #112 Admiral Blue/Black Dana 4:10 Aluminum flywheel Corsa exhaust Watson headers Haibeck chip 470 HP/399 RWHP 1991 ZR-1 #400 White/Red (SOLD) Dana 4:10 Powder coated engine Haibeck performance chip Borla exhaust

10-02-2020	#2
BigJohn Join Date: Feb 2012 Location: Ledyard,CT Posts: 8,331	Re: Missing a gear shift I have shifted with out the clutch just to get it home. That was five years ago; still no transmission problems.

10-02-2020	#5
Norwegianmopar Join Date: Mar 2018 Location: Norway Posts: 346	Re: Missing a gear shift "If the revs were right"...I guess I was in the 6-7000 rpm range (as usual). I have driven it hard and a lot and never missed a gear before, so that's why I ask if it's bad or not. I love "using and abusing" it as it's an awesome sports car with an amazing power band.Screenshot_20200903-104112_Gallery.jpg Sent from my SM-G955F using ZR-1 Net Registry mobile app __________________ Roy Martin 1994 ZR-1 #112 Admiral Blue/Black Dana 4:10 Aluminum flywheel Corsa exhaust Watson headers Haibeck chip 470 HP/399 RWHP 1991 ZR-1 #400 White/Red (SOLD) Dana 4:10 Powder coated engine Haibeck performance chip Borla exhaust

10-02-2020	#9
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,061	Re: Missing a gear shift Here is a video of whats happening when you shift gears. The whole idea of a synchro assembly is to match the speed of the gear shaft with the teeth on the gear itself. So when you "miss a gear", what actually is happening is the shaft and the gears are spinning at different speeds and dont mesh when they should. That causes the grinding sound and since the blocker rings are generally made of brass, they will wear out the fastest. The teeth wear out as well as the cone portion of the blocker ring. I have not opened up a ZF, but many Borg Warners when I was wrenching for a living. We used to rebuild them in house when I worked for Anheuser Busch many years back. The principle is the same. https://www.youtube.com/watch?v=0Bqs-oHBBQk

10-02-2020	#10
tccrab Join Date: Oct 2004 Location: Folsom CA Posts: 1,663	Re: Missing a gear shift The ZF6 is a very stout transmission, but there are limitations. Speed shifting won't hurt it a lick. Missing a gear while speed shifting, we'll not so much. The 2nd and 3rd gear synchros are fairly delicate. You will know if they need attention. 'Crabs