Downshifting Question

[genix]

Currently I own a 98 Nissan Maxima (MT)...
When downshifting from 5th to 4th, sometimes I hear a "thunk" or "thud" sound from under the hood....also sometimes hear this when I'm at a stand still, and try to start going into reverse.

If I was attempting to go from 2nd to 1st, or redlining while in gear and trying to go into a lower gear, I wouldn't be surprised at this, but it seems like if you wait for the rpms to go down to reasonable levels, this shouldn't happen.

Doesn't happen often, and I can stop downshifting altogether, but I was curious if anyone knows why this is happening, and what the sound is.

[MaxPayne]

Check your engine mounts. Its likely that they are on their way out for one reason or another. Also, do you have an aftermarket y-pipe? If so, check the clearances on that.

On another note, downshifting should really ONLY be used if you are intending to accelerate. Downshifting to slow your car down is one of the ways you make a good transmission go bad.

Besides, what would you rather replace? Brake pads? Or a transmission?

I'll take door #1.

[Lordrandall]

If you downshift correctly it isn't any more wear on your car than regular driving.

Besides, if you are in the correct gear and the light turns green, it's Go Time!!

[MaxPayne]

Originally posted by Lordrandall
If you downshift correctly it isn't any more wear on your car than regular driving.

Unfortunately, that's not most drivers. Using your engine to slow down your car puts unncessary stress on your engine and tranny. Every car by law is equipped with a device designed specifically for slowing down every vehicle. They're called "brakes". Its the left pedal in an automatic and the middle pedal if you have a manual.

[DiS]

Originally posted by MaxPayne


Unfortunately, that's not most drivers. Using your engine to slow down your car puts unncessary stress on your engine and tranny. Every car by law is equipped with a device designed specifically for slowing down every vehicle. They're called "brakes". Its the left pedal in an automatic and the middle pedal if you have a manual.

ROFL!!!!!! If you downshift, you save the brakepads but you kill your tranny (slowly but steady) If you brake your brakepads wear out, but tranny is still in good shape. Thats what brakes are for... Unless you like spending insanely crazy amount of money on new tranny. UNLESS you downshift properly.

[Jetts]

kinda off topic i guess but when i stop i put my tranny in nuetral it is a manual is that bad for the tranny?

[Paonessa]

Originally posted by 96Hatch
kinda off topic i guess but when i stop i put my tranny in nuetral it is a manual is that bad for the tranny?

as opposed to sitting in gear with the clutch pressed in with stress on it, i'd say no. i leave mine in neutral

[Jetts]

cool i was think that it would be less wear on clutch and tranny but just wanted to ask

[MaxPayne]

If you leave it in Neutral, there's little to no wear on components. If you sit at the light with your foot on the clutch, that may produce a little wear on the clutch thrust bearing, but it really doesn't matter. If you think about it, the clutch is only supposed to be used intermittently.

[Lordrandall]

Originally posted by MaxPayne


Unfortunately, that's not most drivers. Using your engine to slow down your car puts unncessary stress on your engine and tranny. Every car by law is equipped with a device designed specifically for slowing down every vehicle. They're called "brakes". Its the left pedal in an automatic and the middle pedal if you have a manual.

Holy crap, my car has brakes as standard equipment????



Most people I've driven with who drive a stick need a few lessons, myself included.