Manual Trans Fluid Change
 

I recently took my Mazda 3 to the Dealership for an oil change. They said something about changing the fluid in my trans.( 5 speed std) . Is this really needed....I've got over 50,000 miles on this 3.:cool:

It's only necessary if you feel sorry for them and want to give them some of your hard earned money. If they press you on the issue ask them to show you in the Mazda service manual where it says to replace the tranny fluid (Hint: it doesn't).

IIRC the manual recommends changing the trans oil at 60,000. If you feel any significant "notchiness" or live in an area that gets cold then you may want to consider swapping to synthetic.

I don't know what manual you're looking at, but I'm looking at the manual for my 2009 right now and it makes no recommendation for changing the gear oil for a manual transmission in a Mazda3 in either Schedule 1 or Schedule 2, regardless of time or mileage. Maybe older Mazda3s are different. Yes, no?

I'm with shipo. It's not in my manual either.

There is no recommendation in mine either (2007) though I did find where it says to inspect it, think it was like every 20k miles or something.
Personally i'd recommend changing it if you have 50k on the car, there has to be some grime from gears that's kicking around in there which can't help the life of the trans. I'm at ~34k and thinking of changing it just to be on the safe side... and see if it changes the mileage at all.

Grime from the gears? Highly unlikely. Why? Because manual transmissions don't "dirty" and/or "cook" their lubricant like engines and automatic transmissions do (no combustion gasses, no wet clutches and precious little heat generation). I've drained manual gearboxes after nearly 200,000 miles and the gear lube looked like the day it was installed at the factory.

new gears could easily have some unpolished edges that would chip off over time, all depends on the quality of the internals. Though remember that oil does break down with time & heat - how much i'm not sure, but i'd error on the side of safety. This is a price of 10 oil changes in the life of your ride, or in an extreme case over time a new transmission instead, take your pick.
I know a differential is different than a trans, but the rear end on my RX7 needed new lube yearly due to a previous owner not changing it at all. SO something was wearing / breaking down and dirtying up the oil.

A few bits of metal falling to the bottom of your tranny case are completely inert and will not dirty the gear lube in any way-shape-or-form. That said, my bet is that for every singly grain of metal from an "unpolished edge", there are dozens (if not hundreds) more from normal wear.

FWIW, "oil" will NOT break down at all with time and heat (at least not the heat generated by a manual transmission, even if it's used to tow or for racing). My guess is that you're thinking of engine oil where the additive package breaks down over time and with high applications of heat; the oil itself is typically good to go for a long-long time.

As for differentials, if we're talking about an open diff, then the gear lube should be good to go for the life of the vehicle, however, if we're talking about a clutch type limited slip differential, then yes, the oil needs to be changed on a periodic basis as the clutch material can in fact dirty the oil.

Personally I don't trust dealers because they are crooks. (When it comes to servicing your car) Second if you are going to change the tranny fluid do it yourself. I think that is easier than an oil change. Do you really need it? Probably not. Will it hurt your car? No. Get a second opinion just for kicks on this one. Did you ask the dealer how much will it dent your pocket? Just change it and use redline or amsoil. Done.

Thanks for the clarification & information, I thought all oil broke down over time, not just engine oil. And I hadn't connected the dots, but it was a LSD rear end that I observed getting dirty - guess that's a good reason for it.

If you want to change it, not too difficult to do it your self. You need to
know capacity and buy enough 75w-90 gear oil. About 6 bucks a quart
at your auto parts store. Elevate the front end safely using ramps or
jack stands and drop the splash shield which involves removing 7 small
hex screws and 2 plastic plugs by prying center down then pulling plug
out. ON the tranny you have a drain bolt (dead bottom) and fill hole
about midway up. Unscrew drain hole bolt, drain it and put tightened
bolt back in. Next open fill hole and fill tranny until fluid is level with
hole and starts to run out then close her up. Oil is easy to pour because
quart containers have long snout to insert in to fill hole. If you are not
sure about needed maintenance, check you owners manual. The bolts
are large and appear to holding nothing together.

Nah, you're probably right, no need to change it. However, some car mfg.
as a selling point, in their normal maint. schedules, do stretch maintenance.
intervals. One car maker recommended, for normal driving, oil change at
10k and filter at 20k. Well, I opted for oil and filter at 5k. Like you said
refer to your owners manual for recommended maintenance.

Have to add to this. It seems, and becoming more prevalent, that dealers
are making up procedures and charging big bucks. Beware of throttle
body cleaning and checking and adjusting self adjusting brakes. Spoke to
a kid, while at the dealership, and they hit him for $300 to re-tune his
suspension because he drove on city rather than suburban streets. This
was not an exotic car, just a regular family sedan.

Your comment is completely out of context. The manufacturers that recommend extended oil and filter changes (none that I know of recommend a mid-term filter change) do so because they've engineered their engines to the point where that's all of the maintenance they need or require. You must also consider that these same manufacturers go the extra mile (so to speak) by doing things like requiring synthetic oil that meets standards that are way-beyond typical "synthetic oil", extra large oil pans and sumps, extra large filters, and software that analyzes the driving pattern so as to predict when the next oil change is needed. Said another way, I don't believe there is a single manufacturer out there with a target oil change interval greater than 10,000 miles that doesn't also employ software to alert the driver when the next oil change is due.

Recommended oil change.
 

Well, I didn't want to mention any names, but I have the 2005 Accord
coupe owner's manual in front of me. Normal driving sched recommends
oil change at 10k or 1 year and oil filter at 20k or 1 year. Severe sched.
oil at 5k or 6 months and filter at 10k or 1 year. Other than the dip stick
and the above sched, a maintenance light does come on, but if its pegged
to either sched, I'm still sticking with oil/filter at 5k which is the same as
Mazda 3's 2007 sched. 2. I know synthetic oil may be better and last
longer, but I personally don't want any kind of oil in there for more than
5k or 6 months. Honda recommends buying their oil (wonder why) but,
do say, not required, you can use synthetic oil. As far as the oil pan,
sump and filters, they don't look especially large.

It seems that I misread your original post. I thought you said two filters for every oil change when you actually said the opposite. The thing is, one filter for every two oil changes has been a time honored tradition that goes well back beyond when I started turning a wrench in the mid 1970s, and actually a pretty good idea when it comes to extending the life of your engine.

Yeah-yeah I know, "Gasp! How could you leave a dirty oil filter on your engine after you've drained the dirty oil out and put clean oil in its place?"

Simple really, the fact is that as oil filters age, they filter BETTER than they did when they were new.

Speaking directly to your Accord, a 10,000 mile oil change is by no means a long oil change these days, and if you happen to go over to the Bob is the Oil Guy dot com web site and look at the Used Oil Analysis database, you'll see hundreds (literally) of Honda UOAs that have been performed after 10,000 mile oil changes. When you look at the data contained in said UOAs you'll see that even the semi-synthetic Honda 5W-20 oil is good to go for an easy 10,000 miles under normal driving conditions.

FWIW, when I was talking about larger oil pans and filters I was thinking of the way BMW does things with 7 and 8 quart oil pans and very large canister oil filters. That plus synthetic oil that meets the rigorous BMW-LL01 oil specification and 15,000 miles is a cinch to achieve for the oil.

That "maintenance required" light is nothing more than a dummy light on Honda vehicles that come on XXX miles after it was last manually reset by a human. There is no sensor that turns it on. The light can be reset by you (instructions are in the manual) and won't come on again until whatever amount of miles the manual says it will.

I used to have a 1991 Honda Accord. There was a small key hole in the gauge cluster that reset the light. The newer models don't have that and use some other sequence.

Oil change
 

Appreciate your feedback, that was some pretty interesting stuff. Been
turning wrenches since the mid 70's myself and it seems the more I learn
am aware the less I know. Presently I am maintaining my 05 Accord, wife's
09 Elantra, Son's 07 Mazda 3S and Daughters 07 Milan. So can always
use good advice. Posted a large description on how one Mazda dealer
handled 07 3S clutch replacement. You might think, after reading, I was
exaggerating the damage they did, but it's true. By the way the milan's
3.0 six takes about 6 1/2 quarts and a rather large oil filter. F4 Corsair?

Yup, got a shot of that bad boy as it was doing a mock straffing run on a sail boat I was a guest on in Camden (ME) Harbor back in, ummm, 1997 or 1998. Turns out it was at the air-show the next day and I got a chance to get up close and personal; the plane is a Goodyear version officially dubbed an FG-1D. :)

Regarding the damage from the clutch replacement, I'm thinking small-claims court.

Clutch replacement.
 

Live on Long Island and have plenty of options, like Nassau Consumer
Affairs, AUTOCAP and so forth. In this case I feel like I rescued a
kidnapped kid and not going to loose sleep over $500 worth of parts.
Have engaged in combat with these folks before, won some loss some,
had one transmission facility declare bankruptcy to avoid paying when
New York State DMV awarded me the case. Heard passenger side motor
mounts are failing on the 3'S, so that one might have been legit. Speaking
of motor mounts the tranny anti torque seems to be getting a little too
elastic.

Maintenance Light
 

Yeah, I kinda figured on that, and that's why I give it little heed. To reset
mine you hold the trip mileage button in and turn on the ignition. I know
it's not a Mazda issue, but as a point of interest, I've read some 08 and
beyond accords, with 30 or 40% oil life remaining not registering any
oil on the dip stick. Thanks for your input.

Yeah I hate lights like that lol.

No prob