Burning Smell After Downshift

[x75x]

Downshifted to 2nd gear coming off the freeway today. Was still at about ~45mph so engine went to about 5000rmp after the downshift. Thought I smelled burning plastic or something after.

My car only has about 700 miles...did I rev it too high since it's not really broken in yet? Any thoughts?

[3dplane]

Guess #1: Clutch slipped while trying to bring the engine RPM up to match the vehicle speed for the gear selected so burning clutch disc smelled.

Downshifting to second gear at that speed is also killing the synchronizers inside the transmission as they are trying to bring two shafts spinning at very high RPM difference to the same RPM. They are friction devices,doing this wears them out and when that happens it will take a very experienced driver to shift the trans without "grinding" the gears. (basically ruined transmission)

Guess #2: You picked up a plastic bag that stuck to the exaust under the car.

[fatcat]

my thought...I would avoid 2nd gear while going 45mph...In my opinion, that is too fast for this gear

[Cani Lupine]

Yeah, you burned up the clutch a bit. Since you said "the engine went up to 5000 RPM," it sounds like you failed to rev match. You're supposed to blip the throttle to bring up the RPMs to match the lower gear when downshifting with a manual.

Unfortunately, the pedal spacing doesn't really make for good heel-toe shifting, or at least I haven't spent enough time to try to learn how to do it in the Mirage. In my Aspire, I was able to rev match well enough, but I drove that car for about 3 years, and it was my first car with a clutch.

[x75x]

Yeah, you burned up the clutch a bit. Since you said "the engine went up to 5000 RPM," it sounds like you failed to rev match. You're supposed to blip the throttle to bring up the RPMs to match the lower gear when downshifting with a manual.

Unfortunately, the pedal spacing doesn't really make for good heel-toe shifting, or at least I haven't spent enough time to try to learn how to do it in the Mirage. In my Aspire, I was able to rev match well enough, but I drove that car for about 3 years, and it was my first car with a clutch.

Yeah, I thought I gave it enough gas to match the downshift, but apparently not. Just gotta be more careful on those downshifts I guess.

[MetroMPG]

Unfortunately, the pedal spacing doesn't really make for good heel-toe shifting

I actually thought it was set up decently for heel & toe. But everybody's heels & toes are different.

[3dplane]

Yeah, I thought I gave it enough gas to match the downshift, but apparently not. Just gotta be more careful on those downshifts I guess.

I'm not suggesting to continue aggressive downshifting but if it has to be that way next time,make sure the clutch pedal is released during the throttle blip part of rev matching.

If you did it that way then my apologies and ignore what I'm saying.

If the clutch pedal is pushed down during the throttle stomping part of the downshift,then the input shaft of the transmission is not connected to the crankshaft therfore no matter how high the engine is revving,the input shaft is not being revved up to match the speed of the lower gear you are about to shift into.

So during a rev matching downshift say from 5th to fourth gear push clutch pedal in,pull shifter to neutral,let the clutch out,blip the throttle,apply the clutch pedal and put it in the lower gear.

Double clutching. Some old trucks had to be upshifted and downshifted this way to keep the transmission from grinding the gears.

Again if you do it this way then ignore what I said. No one mentioned this so I did.

[Cani Lupine]

I've got bigger feet, so it's more like ball-of-foot and toe.