In third gear, when you let off the throttle, the shifter moves.

Doesn't make any noise or cause any problem, but it is definitely moving and more than before.

Could this be a motor mount problem?

Thanks for any insight

 

Miles on chassis? original motor mounts? done a lot of launching lately/had wheel hop? check your power plant frame.

 

Yes, motor mounts are a good place to start looking. So is the PPF and diff mounts.

Dave

 

117,000 on chasis.
Original motor mounts

 

Mine does the same thing with 12K miles on it. I have been told the diff and motor mounts are weak after 13 or 14 years.

 

If you have the aluminum motor mount arm on the driver's side, it's likely failed by now, but may not be apparent just by looking. These had 87k on them and the only thing holding driver's side together was the weight of the motor.

 

go to banzai-racing.com and get new motor mounts my FD used to do the same thing and i got new polyurethane mounts and i doesn't move at all now.

 

Check the PPF first. If it's on it's way out, it's only short matter of time before it breaks in two, and the sound of a broken PPF banging against the floorboard is pretty crazy.

A broken PPF a while back made my shifter move up and down significantly. With a replacement PPF and new motor mounts, the shifter will still move up and down very slightly. With the PPF and poly motor mounts, my experience is almost no shifter movement at all, and no visible engine movement, even on the dyno. Of all my suspension mods, the poly motor mounts also made the biggest difference in reducing rear wheel hop. Expect some engine vibration below 2000 rpm if you go this route.

 

+1

I have Banzai motor mounts and I agree with all of this statement.

 

nobody mentioned to check the PPF bolts themselves. I once bought an FD where i was sure the PPF was cracked, but the bolts were just loose.

 

You mean the nuts (PPF doesnt have bolts) ? Technically i told him to check the PPF in post #2, which includes the mounting points

 

the banzai mounts are ****, i've seen the grade 8 bolts snap more than a few times and not due to overtightening.

 

Technically...doesn't it have one at the rear into the differential case?
Although IIRC the torque spec is about half those of the nuts.

 

I just knew some smartass was going to bring that one up

Threads into the driver's side rear of the PPF horizontally? I guess it's a bolt, but a pretty wacky looking one at that

 

Just covering it. When people are instructed to check an item, they sometimes forget to check the mounting hardware itself.

 

You can get the Himini poly motor mounts and modify your aluminum mount to fit them yourself. Saves you the cost of finding a steel mount.

I like them.

 

What's involved in modifying the aluminum mount? Do you just drill it out?

 

Listen to this man, he's probably dealt with more high-mileage motor mounts than any of us.

Which mm's would you suggest, Ben?

 

The aluminum arm has a "dome" of material over the area where you'd drill for an anchor bolt. I'm guessing you'd have to grind that flat. How weakened the arm is afterward is a point of debate. Personally, I'd just spring for another steel arm. But YRMV.

 

I had noltec mounts put in by rotaryressurection last year when he rebuilt the motor. There was a little vibration below 2000 rpm when i picked it up, but by the time I drove it all the way back to MI from TN, the vibrations were gone. Couldn't be happier with the upgrade! Shifiting definitely feels more solid now.

The difference between noltecs and other polymounts like banzai's is that there isn't a bolt shaft going all the way through from the engine to the frame - which to my mind provides a direct path for vibration to travel. Check with Fritz Flynn - he had a set when I was looking to buy one last year.

 

My shifter rocks a bit on/off throttle only in the "forward" gears (1, 3, 5), but does not move at all in 2 and 4. I've driven with the tunnel cover removed and the trans is not moving at all when this happens, just the shift lever. The last transmission I had did this too (before it died on a downshift to 3rd on the track). I figure the sliders are being pulled back in those gears for some reason, not sure why there's play there.