5 speed manual transmission to a 6 speed?

I own a 08 Mazda 5 GT (5 speed) and, for the most part, I am a happy 5iver. I've noticed considerably more road noise when the engine turns north of 3K rpm, especially when cruising on the highways in 5th gear. Following some of the threads here, I've noticed that markets outside North America have models with 6 speed manuals and some are even equipped with Dynamic Stability Control.

Are there swaps available? If so, how difficult would the conversion be?

I can't help but believe having a 6 speed manual would help in the fuel economy numbers, reduce engine speeds, and reduce interior noise. Am I off-base?

I wish a swap would be available , but some things to consider:

• 6MT is available only for the 2.0L in Europe/Asia, not the 2.3L, so I'm not sure what is the effect on a shift box, maybe not a bolt-on option?
• See this chat with a member from Sweden (2008 Mazda5, 2.0L, Gas, 6MT). At cruising speed I did not see a radical difference on RPMs, so I'm not sure if it would help the fuel economy case. I would love one regardless (naughty)

coolmazda5 said:

The pic shows 120Km/hr, which is around 75MPH and I see ~3400RPM. Were you on 5th or 6th gear?

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Blue Swede said:

I was on 6th gear

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coolmazda5 said:

I had the chance to check the RPMs at 75MPH. It hovers around 3500RPM so I don't see a drastic difference from yours. It may be a similar ratio as the US/Canada 5th gear so to compensate for the 2.0 vs. 2.3 engine power, fuel economy at other speeds or blah. I'm not an engine expert, so my comment may be quite flawed anyway (boom02)

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Now, I'm either deaf or quite used to 4cyl car noise, but I always thought that my cars in 5th gear were so quiet even on high RPMs (i.e. 3500-3800RPM) compared to other cars I've owned (scratch)

coolmazda5 said:

I wish a swap would be available , but some things to consider:

• 6MT is available only for the 2.0L in Europe/Asia, not the 2.3L, so I'm not sure what is the effect on a shift box, maybe not a bolt-on option?
• See this chat with a member from Sweden (2008 Mazda5, 2.0L, Gas, 6MT). At cruising speed I did not see a radical difference on RPMs, so I'm not sure if it would help the fuel economy case. I would love one regardless (naughty)

Now, I'm either deaf or quite used to 4cyl car noise, but I always thought that my cars in 5th gear were so quiet even on high RPMs (i.e. 3500-3800RPM) compared to other cars I've owned (scratch)

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Compared to other cars revving past 3K at cruising speeds, the Mazda 5 handles noise creep quite well (a major selling point in my purchase). And the gearing does give the car usable passing power without down shifting. Unfortunately, I shifted from a 2004 Mazda 3 2.3 - 4 spd auto which had considerably less noise at highway cruising speeds.

What about the DSC? Would there be an aftermarket module that could work with the existing ABS? We get quite a bit of snow North of the 49th parallel and any stability aids along with the prerequisite snow tires would help....

av474 said:

Compared to other cars revving past 3K at cruising speeds, the Mazda 5 handles noise creep quite well (a major selling point in my purchase). And the gearing does give the car usable passing power without down shifting. Unfortunately, I shifted from a 2004 Mazda 3 2.3 - 4 spd auto which had considerably less noise at highway cruising speeds.

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Yeah, I noted that in 2 rentals once: A 2007 Mazda5 and a 2008 Mazda3, 4AT both.

av474 said:

What about the DSC? Would there be an aftermarket module that could work with the existing ABS? We get quite a bit of snow North of the 49th parallel and any stability aids along with the prerequisite snow tires would help....

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I hear ya. The DSC topic has been discussed plenty here as it is available everywhere except in NA. I'm not sure how complex is DSC so to speak of, but I'm assuming is not bolt-on either as it considers a lot of factors like the car's gravity center, weight, wheel distances, etc., which are unique for each car . I'm not trying to override the DSC safety (I know some people may bash me here, LOL) but I'm OK with the current car design, ABS and, if I read correctly the other day, the Mazda5 ABS includes EBD (folks, keep me honest here).

a couple of comments.

1. The cruising speed is a bit higher than many other vehicles, but it is simply a reality of the vehicle and gearing. I can remember cars past with no OD gear running 3500+ RPM at 60MPH. If you want a 6-spd, I imagine that 1 from an overseas 2.0L Diesel might work, but would be near impossible to source. Also, the 6-sped is most likely close ration and wouldn't lower the final RPMs that much Maybe a MS3 tranny, though one would thing it may be abused as well.

2. I'm really torn on DSC. I can see the value in an emergency situation, but I've never had it available and have had to rely on my skills more than a few times. I have to imagine that it isn't included in US cars for cost reasons.

Also, with snows, I have found the 5 to be a very stable vehicle. as ours was new last winter, I had to train extensively using my very unconventional snow driving acclimation method. Basically, I find a large open parking lot and perform emergency maneuvers. Not so much "donuts" like the crazy kids (I was one not too long ago), but thing like emergency braking and pulling the e-brake at say 20-25MPH to try and drive through the slide. Sure it's fun, but really is an educational tool.

I found the 5 to be quite controllable and even attempted to put it into a spin, but was unable to. I wouldn't try that on the standard tires. Also, the 2nd gear start in the AT is quite helpful for slippery situations.

if you were to swap it, a mazda dealership could reprogram your pcm incodes to think it had the as built data of the perticular model 2.3 with 6 speed. Inquire with yoru dealer and if you get serious about this swap, drop me a line and i can show your local dealer on how to input as built data. You would need all trans components and then the vin of the car that has a 2.3 and 6 speed with all options you have, i mean dsc, tpms, ect.

i think it can be done but definitly no waranty. All that determines the difference if a car ahs dsc, tpms, ect is the vin as built data. Some people that install aftermarket rims with tpms(or without because of the rims) i have twice now reentered as built data and jsut didnt reprogram that module for the tpms

Not confirm yet but I believe the cheapest way to low the rpm is swap the final drive gear set from mazda3. According to mazda usa website... The gear ratios from 1st to 5th are the same, but mazda3's FD is 4.105 and mazda5's FD is 4.388.

If you want to lower the RPM further... try the 5th gear set from NSN...
http://www.nsnmotorsports.com/product_info.php?cPath=30_78&products_id=206

king57721 said:

Not confirm yet but I believe the cheapest way to low the rpm is swap the final drive gear set from mazda3. According to mazda usa website... The gear ratios from 1st to 5th are the same, but mazda3's FD is 4.105 and mazda5's FD is 4.388.

If you want to lower the RPM further... try the 5th gear set from NSN...
http://www.nsnmotorsports.com/product_info.php?cPath=30_78&products_id=206

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The 5th Gear Swap is an intriguing option. Especially if it can be done without having to drop the tranny. Would the PCM need reprogramming if the FD ratios are changed?

I miss the days when cars weren't run by computers......