shoelick

I just purchased a 2002 mid-cycle PR5 with a 5-speed. When I go in reverse, I hear a really loud grinding noise and the natural whinning noise that a manual makes in reverse is rediculously loud. Is this charactersitic of a Mazda manual tranny, or am I in trouble?

alcoholiday

shifting into reverse from a standstill or while moving forward very slowly?

from a standstill, there shouldn't be much of a noise but if you're creeping forward, it'll grind. make sure you're at a complete stop before shifting into reverse.

as for the whine, mine seems to be no louder than any other little car i've heard.

Tetonman

First of all, congrats on joining the P5 Club.

As to the grinding sound, it is normal in the first couple of months for the stick to 'grind' or hit the guards when you shift. Right now, your shift path is very tight and unless you shift almost perfectly, you will hear the sound of the stick hitting the guard. Over time, this will lessen.

As far as the loud sound when you are in reverse, that's normal too. It does seem that the P5 really whines when in reverse and driven quickly. The only way to lessen the noise is to slow down when driving in reverse.

These issues you have are very common in all manual transmission cars. Don't worry, just back up to where you need to and then haul a$$ forward.

Tetonman

Toolin

My 91 DX, 95 DX, and my 02 P5 have a very load "whine" when in reverse.

nramsey

Most manuals do. I believe it's due to the gears being straight cut, instead of helical or something like that? Cheaper/easier to make, but can be noisy.

As for the grind, I don't think that's normal. Like a previous poster said, you must be COMPLETELY stopped to engage reverse, otherwise it will grind.

Tetonman

to shifting in reverse, that will stop most of the grinding sound.

As I don't know if the original poster is familiar with a 5 speed, I wanted to mention the guard that protects the transmission from being shifted into reverse while moving forward. That guard makes some noise when first shifting into reverse. It's not that loud, but some newer manual drivers get concerned when they hit the guard and the tran makes a strange sound. That is normal.

Tetonman

bizsnatch

i find that often when i park overnight it is difficult for me to shift into reverse to back out of my driveway. my driveway is slightly sloped backwards and it feels like i am in reverse but when i hit the gas it pops out. to avoid this, i release the parking brake and roll back a foot or two before trying to use reverse. anyone else have this?

Tom Slick

there is no actual "guard" that keeps you from shifting into reverse. the gears for reverse in almost all transmissions are straight cut because the gears themselves engage and spin only when you shift into reverse, reverse has no syncros. it is the gears themselves that keep you from attempting to shift into reverse
all forward gears are always engaged and spin all the time, and a collar engages the syncros and lockes the gears to the appropriate shaft.
take a look here
how transmissions work

Sir Nuke

FIRST Shoelick, Welcome to our happy little corner of the net. There is a BIG fridge in the corner with just about anything you can think of in it...help yourself...of course only take what you can LEGALLY have. (stash)

make yourself at home on one of the big fluffy couches, kick your shoes off, put your feet up on one of the tables....and take it easy.

oh...btw....every once in a while a food fight breaks out...so you may not want to wear nice clothes here.

Welcome!! (stash)

SECOND, our cars WHINE like pre-schoolers without a nap when in reverse....its normal...don't worry about it.

shoelick

I figured as much. I am just used to automatics so much that these noises are new to me. I love my new 2002 mid-cycle PR5 and am so happy with it. I'm sure it's Japanese origins will prove to be reliable and I have nothing to worry about. Thanks to all my fellow PR5 brethren out there for your input and information on this matter. see you on the road.

arl240

I am just comfirming what nramsey said, the reverse is a straight cut gear compared to a helical cut gear. Straight cut are significantly cheaper to manufacture, but power transfer and noise are problems since the hole tooth strikes the other at once versus a gradual contact with the helical cut.

On an off topic, does anyone know where I can find a planetary gearbox for 150 hp motor that has a 24:1 speed reduction. I have to find one for some clients of my company.

Evil Homer MP5

I have a question that is realted to this.

This is my first car that is a manual, i find that when i'm slowly moving backwards, and put it in reverse, it still grinds.

is this normal as well??

codename:apexer

shoelick, I've noticed the same thing. After the reverse gear is engaged and you release the clutch. Press gas pedal and go backwards. Then (while rolling backwards) you let of the gas and it makes the loud reverse transmission noise. The whinning in reverse is always there on a manual. My nissan never made the noise, or too that extent. Thats why I was concerned, but it must be normal.

oh yeah, I'm brand new here/02 p5 white

Doomer_MP3

I believe there is a guard for 5th->Reverse though, and I believe its on most cars. At a stand still someday try it. Go into 5th and have your window open. You'll hear a clank not characteristic of other shifts. Then try going into reverse and it will be blocked. If you go from 5th to some other gear you'll hear a clank of that blocking mechanism disengaging...

Chris

itaras1

OK
1st The Noise when baking up is common on all manual trans.
2nd When you shift to (R) YOU MUST STOP AND THAN SHIFT THAT WAY YOU DONT GRIND YOUR TRANNY.

IM NOT EXPERT BUT I SURE THAT ITS BETTER TO TAKE IT EASY!

Remember YOU GOT A SWEEET RIDE NO NEED TO RUSH