5AT in Mazda5
- Thread starter Cybspur
- Start date
I will say you could probably pick one up for dirt cheap. Since you seem to be a no-frills-whatever-gets-the-job-done-for-cheap kinda guy, this or a PT Cruiser might be better alternatives. I thought PT Cruisers were terrible until I got one for a rental, and I was really surprised... not nearly as bad as I thought.
rodslinger
Member
Overdrive is different as well as all other rations. Better first gear for starting off and better gear spacing to keep in the power band. Difference are...
Type Type
4AT, FN4AEL........ 5AT, FS5AEL
1st gear 2.816:1...... 1st gear 3.620:1
2nd gear 1.497:1..... 2nd gear 1.925:1
3rd gear 1.000:1..... 3rd gear 1.285:1
4th gear 0.725:1 ......4th gear 0.933:1
................................5th gear 0.692:1
Final drive 3.904:1.. Final Drive 3.863:1
Reverse 2.648:1...... Reverse 3.405:1
I think you are making the assumption that that changing gears causes additionall wear and that if a transmission needs repair it will cost more simply because it has one more gear. The 5 speed auto may have fewer parts and may be a more efficient design leading to LESS problems and lower cost of repair.
Type Type
4AT, FN4AEL........ 5AT, FS5AEL
1st gear 2.816:1...... 1st gear 3.620:1
2nd gear 1.497:1..... 2nd gear 1.925:1
3rd gear 1.000:1..... 3rd gear 1.285:1
4th gear 0.725:1 ......4th gear 0.933:1
................................5th gear 0.692:1
Final drive 3.904:1.. Final Drive 3.863:1
Reverse 2.648:1...... Reverse 3.405:1
I think you are making the assumption that that changing gears causes additionall wear and that if a transmission needs repair it will cost more simply because it has one more gear. The 5 speed auto may have fewer parts and may be a more efficient design leading to LESS problems and lower cost of repair.
starlightmica
Member
- :
- 2007 Mazda5 Sport
Have you tried autobytel.com or carsdirect.com? They give you a price over the phone.
I got my 5 scanning the weekend newspaper auto ads - $16,999 plus freight, etc.
That shifting causes wear in an automatic transmission is not an assumption. That's why pickups have overdrive lockouts for towing; so that the tranny isn't shifting so often. That the 5 speed has fewer wear (and other) parts than the 4 speed is a fantasy. Whether a specific shop would charge more or not at this point is debatable. Ultimately, additional gears simply push up the cost of rebuilds for everyone, though initially those with more gears pay noticeably more than others.
This particular 5-speed application may be worthwhile and even nice for some reason, but a CVT would be better for all aspects under discussion, as well as simpler, lighter, and cheaper.
Thanks for the post! Still quite a spread between 1st and 2nd and, in fact, looks to be larger plus a lower final drive. Same with 2nd to 3rd. Wonder how it's gonna perform. Looks like 3-5 should be better suited for our little 2.3L.
You can bet highway mileage is gonna be up! 
You are wearing the transmission the moment the engine is started. It's a matter of more or less wear.
The reason for OD/OFF for is to raise engine RPM thus higher transmission pump rate (to remove additional heat caused by towing) and engine braking.
In case of Aisin 3XX or A75X transmission, T/C remain locked to reduce heat generating.
I don't see a significant difference in top gear highway RPM.
It is when the 5th gear & Final drive added together make the different...
rodslinger
Member
The OD lockout is as much to reduce strain on the engine and keep it in a more efficient range under load as it is to keep the torque converter locked in a lower gear. The slipping converter produces a LOT of heat and lends to fluid degradation a lot more than a gear change does.
I haven't paid attention to the 5AT design so can't say for sure it has fewer parts (as you can't claim a definate it has more either). I did say MAY have. Big difference there. And additional gears do not automatically equal higher repair cost.
I calculated about a 150 rpm difference (@ 60mph) with the 5-speed lower. Sure, not huge but enough to make a difference.
The OD lockouts are primarily (nearly exclusively) to prevent transmission failures, plain and simple. They DO have other benefits, I freely admit that. Those benefits are miniscule compared with preventing transmission failure.
I will argue all day that additional transmission gears of themselves DO equal higher repair costs (to the shop). I will grant, as I did in my earlier post, that the charge to the customer may or may not be higher, though ultimately it will make the charge to all customers higher chiefly because business responds to customer complaints if they're loud and frequent enough. Folks complain about having to pay double what 'everyone else' pays, even if the reason is clear and just. When everyone pays a fairly similar (though exhorbitant) price, people tend to complain much less.
Not sure what the big deal is with repair costs. The thing comes with a 50K mile warranty standard.
And since this seems to be a tranny that is already in production elsewhere and since the move is towards smaller displacement, higher revving engines where transmissions of 5 or more gears is common place seems to me that repair costs will stay the same relative to inflationary forces. Supply and demand; the supply for repair parts will be higher......well provided the transmission sucks.
4-speeds are old school and using them makes it increasingly difficult for manufacturers to produce engines that not only meet emission requirements but performance requirements (market driven) as well.
I'm no Mazda expert but how many other models do they have that will share this transmission? And how many current or 08 models will still use the 4 speed currently in the Mazda5?
And since this seems to be a tranny that is already in production elsewhere and since the move is towards smaller displacement, higher revving engines where transmissions of 5 or more gears is common place seems to me that repair costs will stay the same relative to inflationary forces. Supply and demand; the supply for repair parts will be higher......well provided the transmission sucks.
4-speeds are old school and using them makes it increasingly difficult for manufacturers to produce engines that not only meet emission requirements but performance requirements (market driven) as well.
I'm no Mazda expert but how many other models do they have that will share this transmission? And how many current or 08 models will still use the 4 speed currently in the Mazda5?
I would think you're going to have equal wear no matter how many gears you have. Your car will still shift through them all on the way up to speed, and on the way down. There will be slightly less friction within a tranny with more closely spaced gear ratios; however, it's really insignificant. You're driving habits have more of an affect on tranny wear.
Torque converter lock was developed to increase fuel efficiency at cruising speeds.
Torque converter lock was developed to increase fuel efficiency at cruising speeds.
Fleet use of pickups in environments with relatively low max speeds (under 50 most of the time) and frequent stops even without heavy loads caused high transmission failure rates for the Big 3 about 20 or so years ago. Shortly, overdrive lockout mechanisms were employed by all and transmission failure rates declined significantly in those environments. The same thing was happening under higher-speed towing and was also significantly corrected with overdrive lockouts. That's what they were made for and there is significant extra wear from constant shifting (many owners manuals still talk about the badness of "hunting" for gears in an A/T).
I agree with a bunch of what you say, monsta. I think the most pertinent statement is: "4-speeds are old school"
This is the reason for going to more gears. The market(ing) has determined that more gears=better regardless of whether the numbers reflect that or not, and better=more expensive. I only say it's a shame because some of us are not particularly taken in with such fascinations and wish for lower total cost of ownership. Plus, all of us who buy used vehicles on purpose are very much concerned with repair costs after the warranty period (I know you were joking about that).
I hope that, in the case of the 5, there is sound reason to utilize a 5-speed A/T (as opposed to Lexus or whomever putting an 8-speed A/T behind a 400-hp engine) and that there will be practical benefits that outweigh the costs.
I agree with a bunch of what you say, monsta. I think the most pertinent statement is: "4-speeds are old school"
This is the reason for going to more gears. The market(ing) has determined that more gears=better regardless of whether the numbers reflect that or not, and better=more expensive. I only say it's a shame because some of us are not particularly taken in with such fascinations and wish for lower total cost of ownership. Plus, all of us who buy used vehicles on purpose are very much concerned with repair costs after the warranty period (I know you were joking about that).
I hope that, in the case of the 5, there is sound reason to utilize a 5-speed A/T (as opposed to Lexus or whomever putting an 8-speed A/T behind a 400-hp engine) and that there will be practical benefits that outweigh the costs.
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HotRodSaint
Member
- :
- Mazda5 Touring 5 Speed
By what percentage did transmission failures increase when they went from 3 gears to 4?
I've never heard of an increase in transmission failure when companies switched from 3 speeds to 4 and I don't expect to hear about it when they switch to 5, 6, 7 and 8 speeds either.
I've never heard of an increase in transmission failure when companies switched from 3 speeds to 4 and I don't expect to hear about it when they switch to 5, 6, 7 and 8 speeds either.
rodslinger
Member
I agree that OD lockout it to prevent hunting but the actual shifting isn't what causes the failures. With the OD engaged under load conditions or low speed operation the transmission spends a lot of time with the converter unlocked which produces a lot more heat. The heat breaks down the fluid and promotes oxidation. The heat combined with poor fluid condition is what usually kills the transmission.
HotRodSaint
Member
- :
- Mazda5 Touring 5 Speed
20 years ago! (shocked)
Well that settles it. I'm not buying a 20 year old domestic truck! (protest)
Teardown showed expended wear parts as well as failure-mode bearing and sometimes even gear wear. Maintenance schedules were factory severe-service (which at the time was roughly 30,000 miles) or more frequent so blaming it on fluid condition doesn't fly. Remember that this is compared to identical usage and service conditions with the previous 3-speeds. The problem was essentially cured with the O/D lockouts or with simply keeping the tranny in 3 instead of drive.
Please keep the context in perspective here, folks. I'm not claiming that the 5AT will fail in 70,000 miles. I'm saying that experience shows that more gears = more wear and higher repair cost. Clearly other design adjustments can mitigate the accelerated wear, but if those same design adjustments are applied to a transmission with fewer gears, you still have sooner failure and higher cost on the unit with more gears.
Please keep the context in perspective here, folks. I'm not claiming that the 5AT will fail in 70,000 miles. I'm saying that experience shows that more gears = more wear and higher repair cost. Clearly other design adjustments can mitigate the accelerated wear, but if those same design adjustments are applied to a transmission with fewer gears, you still have sooner failure and higher cost on the unit with more gears.
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